This section deals with the construction of the AVR-HID device, a 6 channel, 10-bit analog-to-digital converter device which communicates with the computer over the USB connection. The design and specifications of the device are given, along with the schematic, parts list, building instructions, usage and modification information.
For a basic introduction to the AVR-HID system please see the AVR-HID project homepage.
The firmware and sourcecode is available from here.
Interfacing computer systems to the outside world is an important aspect of creating new computer music interfaces. We need a means of capturing data from sensors which can be easily used to control a our synthesis engines and musical systems. The interface described in this document gives us such a means. It is designed to be easily accessed on any operating system and from a large number of software applications without the need to write any drivers or additional software.
The heart of this system is the ATMEL ATmega16 microprocessor. The ATmega16 is a low-power CMOS 8-bit microcontroller based on the AVR enhanced RISC architecture. It has 16K of program memory, 1K of RAM and 512 bytes of eeprom. It also offers an 8 channel 10-bit analog-to-digital converter, and is programmable using the C language. While it is not a USB-based controller it is possible to easily implement USB on the system. It also has the advantage of lower cost than most dedicated USB microcontrollers, with the total cost of building the interface less than CAN$20.
This document is a guide to building the AVR-HID interface. It is divided into a number of sections, which cover various aspects of the AVR-HID system itself and describe the process of building your own device. Later sections of the document also detail the development of the system and describe the code used to program the device, for those who wish to modify the interface or to create their own interface.
The document is divided as follows:
- Section 3 gives an overview of the device and it's functionality.
- Section 4 describes the design of the device, its components, layout and schematic.
- Section 5 covers the process of building the interface, including a parts list and suggested suppliers for the components.
- Section 6 deals with the firmware for the device and how to download it to the device.
- Section 7 details the use of the device with a Mac OS X system, through MAX/MSP.
- Section 8 discusses how to program the device, including the necessary software and libraries.
- Section 9 covers the Human Interface Device standard and details the messages which a compatible device must send and receive and how to modify the existing messages.
- Section 10 gives the location of further information and resources on the AVR-HID device.
In its simplest form the AVR-USB device is a 6 channel 10-bit analog-to-digital converter which communicates data to the computer at a rate of 100Hz. All six channels are updated at once, so their is no loss of speed when using more sensors with the interface. This version of the system is created by building the board described in this document and downloading the default firmware.
More complex versions of the system, which offer a different number of channels, or a different update rate can be created by editing the source code for the firmware to create your own firmware. Similarly, up to 10 digital inputs can be added to the system in such a way.
The main aim of this document is to describe the building of the basic AVR-HID interface, as this is the one which the majority of users will most likely use. However, it does also cover the details of programming the device so that new firmware can be developed to allow different functionality.
The steps necessary to create your own AVR-HID interface are:
- Obtain necessary components to build the interface board.
- Assemble the interface hardware and programmer.
- Install the necessary programmer software on your computer.
- Download the firmware to the controller.
- Make some music…..
This section describes the design of the AVR-HID interface, including the board layout, the schematic and the components.
Figure 1 shows the layout of the AVR-HID board, with the main components labelled. The overall size of the circuit is quite small at around 7.5cm by 7.5cm (3” by 3”). Note that the picture shows an early prototype, so only 2 sensor ports are present, a different ISP socket is used and a USB cable is used in place of a USB socket.
The schematic for the board is shown in figure 2.
The following are descriptions of the major components of the AVR-HID board.
While figure 1 shows a USB cable, it is recommended that a USB connector socket is used.
The USB connector is a standard USB connector. You can use either a “type B” or a “type A” connector, the only difference being the type of cable required to connect it to the computer. A “type B” connector and an A-to-B cable is recommended, as this is something of a standard for USB-based devices. The USB connector has 4 connections, one for power, one for ground, and two for signal, labelled D+ and D-.
A standard LED is used to indicate that power has been applied to the circuit from the USB port. It should be noted that the USB system allows a maximum current of 100mA for a single port, which means that should your interface attempt to draw more power than this (such as an interface using many powered sensors) it will not be able to and the LED will not light. In this case, it is necessary to use a seperate 5V DC power supply for the interface.
The In-System Programming (ISP) socket is used to connect the programmer device to the interface to allow dowloading of the firmware.
The 12MHz crystal is required to allow the microcontroller to run at 12MHz, enabling it to operate as a low speed USB device. This speed also allows for other operations, such as analog-to-digital conversion, to be performed by the microcontroller in the time between sending USB messages.
These ports are used to allow the connection of up to 6 analog sensors to the AVR-HID interface. The ports have three contacts, for +5V, Ground and Signal. The +5V and ground are used to activate the sensor, and the Signal contact is used for the output from the sensor. Any 3 contact connector can be used for these inputs, but it is suggested that stereo mini-jack connectors are used, as these have the advantages of being small, cheap, readily available and robust. It is also recommended that the sensors are connected to these ports using shielded 3-core audio cable, as this type of cable is strong and flexible and the shielding will reduce the possibilites of interference with the signal, especially over long distances.
The board in figure 1 shows only 2 sensor ports, which use 3-pin header sockets.
The ATmega16 microcontroller is the heart of the overall system. It performs all of the message processing, formatting and transmission necessary for USB communication as well as the analog-to-digital conversion for the analog input ports.
There are two main steps to building your own AVR-HID interface. These are:
- Obtain the components
- Build the circuit board
This section will deal with these steps. Firstly, the necessary components are listed, along with recommended suppliers and prices. Secondly, some advice for the building process is provided.
The components are available from a number of sources, the choice of which to use is up to the builder. We recommend ordering the components from Digi-key, as they stock all of the necessary components and usually have the best prices. Alternative suppliers for many of the parts include Mouser, Radio Shack, Active Electronics and Addison Electronics. Please note that to the best of my knowledge, only Digi-key stock the microcontrollers themselves.
Table 1 is a full parts list for a single basic board and the ISP cable for programming the board. It includes part numbers to order from Digi-key and prices, all of which are correct as of June 1st 2005. Prices may be lower if the parts for more than one board are purchased together.
|Part||Part No.||Quantity||Unit Price||Total|
|12 MHz Crystal||CTX058-ND||1||1.24||1.24|
|40-pin IC socket||2-641268-1-ND||1||1.88||1.88|
|330 Ohm Resistor||330QBK-ND||5||0.074||0.37|
|62 Ohm Resistor||62EBK-ND||5||0.074||0.37|
|2.2 kOhm Resistor||2.2KEBK-ND||5||0.074||0.37|
Please note that you will also need piece of perfboard on which to assemble the circuit and a USB cable to connect to the device. It should also be noted that we order 5 of each resistor, when in some cases only 1 is needed. This is due to minimum order quantities for Digi-key. You could buy them locally in order to reduce the amount you are buying.
Assembling the AVR-HID board is not particularly difficult for anyone who has some soldering experience. For those assembling the circuit from the diagram, this section will provide some hints and reminders.
The only component that has polarity (i.e. it needs to be oriented in a certain direction) is the power LED. Be sure to align the longer lead of the LED with the '+' mark on the circuit diagram.
For best operation, make sure the crystal and its associated capacitors are kept as close to the microcontroller as possible.
The sensor connectors should use the AVCC line for their power supply. This will ensure the most accurate results from the analog-to-digital conversion.
Make sure to connect the D+ line from the USB port to both pins 2 and 16 of the microcontroller.
The firmware for the AVR-HID device has been built around a number of libraries which enable it to perform complex tasks, such as sending and receiving the USB and HID messages and analog-to-digital conversion. For efficiency, portions of the firmware have been written in assembly, the rest in C. Section 0.8 deals in detail with the code and libraries used for the firmware, and how to edit and recompile the firmware should you wish to do so.
Once you have firmware for the device, whether the default firmware which accompanies this document, or your own custom firmware, you need to download the firmware to the device in order to allow the device to work. This section details the downloading of the firmware, including the necessary cable and software to perform the download, and any additional setup required to use the device.
There are two components required to download firmware to the AVR-HID once it has been assembled:
- Programming cable
- Programming software
However, there are a number of different software programs available for programming the ATmega16 processor, many of which require their own cable. This document will concentrate on using the AVRDUDE software on both a Linux machine and a Mac running OS X. AVRDUDE is also available for Windows.
Which programming cable you use to program your device depends on two factors: which ports are available on your machine and which software package you are using to program.
The simplest cables are used to program the device from the parallel port of the machine. This is the cable which will be used in this document. If your machine does not have a parallel port, there are also serial port cables which can be used. Details of one of these can be found on the PonyProg * website. Alternatively ATMEL make a serial programmer cable which can be used with all of the software packages and is not very expensive.
The recommended programming cable for OS X is the ATMEL in-system programmer, which can be used in conjunction with a USB/Serial converter to allow programming from the USB port of the machine. It is available from Digi-Key. It is part number ATAVRISP-ND and costs $37.86.
The recommended programmer for Linux systems depends on the available ports on the machine. You can either use the ATMEL in-system programmer from the serial port, in conjunction with a USB/Serial adaptor from the USB port, or build a very simple parallel port adapter as shown in the next section.
In order to make the programmer cable it is necessary only to connect 5 pins of the parallel port to a 5-pin plug which can be attached to the ISP socket on the AVR-HID board. The table below, taken from the avrdude website, shows these connections:
|Parallel Port||Programmer Function||ATMega16|
|Pin 7||AVR /RESET||Pin 9|
|Pin 8||AVR SCK (clock input)||Pin 8|
|Pin 9||AVR MOSI (instruction in)||Pin 6|
|Pin 10||AVR MISO (data out)||Pin 7|
|Pin 18||Signal Ground||Pin 11|
The programming software used in this document is AVRDUDE by Brian S. Dean. More information on this package is available on his webpage at http://www.bsdhome.com/avrdude/. It is available for Linux and Windows systems and can be downloaded from http://savannah.nongnu.org/download/avrdude/.
Once downloaded and installed to your system the package will allow you to download the firmware to the AVR-HID.
The steps necessary to download the firmware are as follows:
- Connect the AVR-HID to the USB port
- Attach the programmer cable between the AVR-HID and the computer
- Use the AVRDUDE program to download the firmware
- Set the fuse bits
- Unplug the programming cable and USB cable
Two of these steps require further explanation, these being how to download the firmware and how to set the fuse bits.
To download the firmware with AVRDUDE you must execute the one of the following commands:
On Linux systems using the parallel port adapter:
avrdude -p m16 -c bsd -U flash:w:avrhid.hex:a
The -p m16 parameter tells the software we are downloading to an ATmega16, the <tt>-c bsd</tt> tells the program indicates that we are using Brian S. Dean's programming cable, -U flash:w:avrhid.hex:a tells the program to write (w) the file avrhid.hex to the flash memory and to autodetect (a) its format.
If using the ATMEL serial programming cable the -c parameter changes to -c avrisp giving the following command:
avrdude -p m16 -c avrisp -U flash:w:avrhid.hex:a
If using the ATMEL serial programming cable with a USB/Serial adapter the -c parameter changes to -c avrisp and you need to add a command giving the correct port:
avrdude -p m16 -c avrisp -P /dev/cuUSAXXXXX -U flash:w:avrhid.hex:a
where /dev/cuUSAXXXXX is the handle to the USB/Serial adapter. You can find this by typing ls /dev/cu* in a terminal.
Once this is complete, we now need to set the fuse bits.
The fuse bits are set using AVRDUDE in terminal mode. The fuse bits are used to indicate that the processor is to use an external clock and to determine what forms of programming are allowed for the device. The necessary commands to set these bits are:
avrdude -p m16 -c bsd -t
avrdude -p m16 -c avrisp -t
avrdude -p m16 -c avrisp -P /dev/cuUSAXXXX -t
This puts the program in terminal mode. Now we must set the high and low fuse bytes. At the prompt type:
write hfuse 0 0x89
write lfuse 0 0xff
Then exit the terminal mode. We have now set the microcontroller to operate using a slowly rising external crystal at >1 MHz.
Once this is done you can now unplug the AVR-HID device. When next you connect it to a computer it should automatically be detected as a USB Human Interface Device. The next section deals with how to use the device with MAX/MSP on Mac OS X.
Once you have downloaded the firmware to the AVR-HID device, you are ready to use it with your software. The device is detected as a USB joystick and so can be used with any software package which supports joystick or HID input. It should also be automatically detected by your operating system as just such a device. To illustrate how the device is used, this section will take a step-by-step look at using the AVR-HID with Max/MSP.
The first step in using the AVR-HID is to connect it to the USB port of your computer. This should be done before Max/MSP has been started, or the software will not detect the device. Once you have plugged in the AVR-HID, it is time to start up Max/MSP.
When Max/MSP has started, create a new patch and add the “hi” object, giving the following:
This object is the one which is used to interact with human interface devices. Everytime it receives messages from a human interface device it outputs them. Each message is made up of two numbers, the first being the channel on which the message came in, the second being the value of the message. Each analog input of your AVR-HID is assigned to one channel. The first input is channel 7, the last is channel 12.
To read messages from the object you should use a route object, and connect it to the first outlet of the hi object, as shown in the following figure:
This will output messages for each channel to their representative number box.
Now, to have the object focus on the AVR-HID device, we must send it a message telling it the name of the device on which to focus. So, create a message object with the value AVR-HID like this:
Clicking on this message should make the hi object focus on the AVR-HID and it should display a message in the output terminal to this effect.
The final step in communicating with the AVR-HID is make the hi object poll the AV-HID. To do this create a message, which contains the value “poll 10” and connect it to the hi object's first inlet:
Now, to test if this is working ok, connect one or more sensors to the analog inputs of the AVR-HID. When you have done this, click on the poll message. Now, as you manipulate the sensors, you should see messages coming in on the channels corresponding to each sensor. Each message is in the range of 0 to 1023, representing 0 to 5V from the sensor. Congratulations, you can now use your AVR-USB to control patches in Max/MSP.
The analog-to-digital converters measure inputs in the range of 0 to 5V. The measured voltage is then converted to a 10-bit value by the microcontroller, giving a value in the range of 0 to 1024, which represent 0 and 5V respectively. These numbers are then sent as the data of the HID messages to the computer.
There are six converters active in the AVR-HID device. Therefor each data message from the AVR-HID contains six 10-bit numbers, one for each converter. Even if less than six converters have sensors attached, the message will still contain six numbers.
The value which is transmitted in the message for a converter which does not have a sensor attached will be equal to the value transmitted for the last converter which does have a sensor connected. This means that if you only connect a sensor to converter 1, all converters will transmit the same value. If you connect a sensor to converter 1 and another to converter 3 then converters 1 and 2 will transmit the value of converter 1 and converters 3, 4, 5 and 6 will transmit the value of converter 3.
Programming of the AVR-HID is through the C language. In order to program the system, you must have a number of applications and libraries on your computer. The necessary libraries and applications are:
- binutils (available from ftp://ftp.gnu.org/gnu/binutils/)
- gcc (available from ftp://ftp.gnu.org/gnu/gcc/)
- avr-libc (available from http://savannah.nongnu.org/projects/avr-libc/)
- programmer software (see Section 0.8)
You will have to download and install the necessary packages to your system. Instructions for installation should be available with each package and may change, so will not be presented here. If a guide to installation is needed this article may be of some use. If you are using a Linux system and have installed apt on your machine, you should be able to easily install all of these packages using the apt system and the PlanetCCRMA repository. If you are using mac OSX, you can find detailed instructions on how to get started on Leah Buechley's page.
The AVR-HID sourcecode is built on top of the AVR-USB libraries from Objective Development (see http://www.obdev.at/products/avrusb/). The HID compliance and the additional analog-to-digital code has been developed by the author of this document. The AVR-USB code is included with the source for the AVR-HID and clear comments indicate which portions of the code come from Objective Development.
To compile the sourcecode, you must first download and unpack it. The code is available at: http://www.marktmarshall.com/projects/avr-hid. Once you have downloaded it, you should unpack the file to create the AVR-HID directory. Change to this directory and we will begin to examine the structure of the code.
The first thing to do is to make sure that all of the necessary libraries and applications installed correctly. To do this, while in the AVR-HID directory type:
make clean make
If there are no errors, we know that all the necessary software is correctly installed. If you do get errors, make sure you have correctly installed the necessary libraries and applications.
Now, we can look at the files which make up the sourcecode. In this AVR-HID directory there are a number of .c and .h files. These are:
- main.c - the main loop for the application
- usbconfig.h - the definitions of various USB and HID configuration data
- a2d.h - the analog to digital conversion routines
There is also a subdirectory named usbdrv, which contains the code for the usb and hid communication. The main files in this directory are:
- usbdrv.h - declarations of usb functions
- usbdrv.c - definitions of usb functions and data structures and HID data structures
- usbdrvasm.S - assembly code for timing-critical sections of Objective Developments AVR-USB
Of these 6 files that make up the AVR-HID system, there are 3 which might need to be changed when programming new firmware for the AVR-HID. These are main.c, which is where the main code for the operation of the AVR-HID goes, usbconfig.h, which contains the definitions of the device configuration data and usbdrv.c which contains the messages which are sent in response to the standard USB and HID requests from the computer.
The main.c file contains the initialization and main loop code for the AVR-HID. The functions which initialize USB and set up the interrupts to respond to the USB messages are contained here. The main loop (marked in the code) contains the calls to the analog-to-digital conversion functions, the conversion of the data to the format required for the USB messages and a call to the usbSetInterrupt function, which sets the data to be sent the next time data is requested by the computer over the USB connection.
If you wish to change the main operation of the AVR-HID you will need to edit code in the main loop. To add more analog-to-digital channels to the system, you will need to call the conversion functions for the additional channels, format the data in the required message format, and edit the call to the usbSetInterrupt function. If you wished to use digital inputs, or activate digital outputs, this code would also go in the main loop.
The formating of the data messages for USB responses is covered in section 9.
This file contains definitions of the USB parameters such as device type, class, name etc. These can be edited when modifiying the AVR-USB to interact with the USB in a different way. Details can be found in the USB specification.
This file contains the main functions for interracting with USB and the definitions of the various decriptors which a USB device must provide during the enumeration process. The parts which you are most likely to need to change are these descriptors. More information on the descriptors can be found in section 0.9, on the USB developers site, and in this article.
The building of the firmeware is controlled by a Makefile. If the changes you have made are only within the files already included in the Makefile then you will not need to change the Makefile. In this case you can build the firmware with the command:
and install the firmware on to the AVR-HID using the command:
If you have added new files to the sourcecode, then you must edit the Makefile to add these files to the compilation. In this case, add the name of your file, with a .o extension to the OBJECTS line in the Makefile. This makes the objects line look something like this:
OBJECTS = usbdrv/usbdrv.o usbdrv/usbdrvasm.o usbdrv/oddebug.o a2d.o main.o yourfile.o
You can then build and install the firmware using the commands detailed above.
The USB standard details the way in which USB devices should operate in order to be detected correctly as USB devices. In order to meet this standard, there are certain processes which a device should follow and certain messages which it should recognise.
The requirements for a USB device are:
- must follow USB enumeration process
- it must have a device descriptor and configuration descriptor
- must contain a control endpoint for control messages
- must recognise standard control messages
Additionally, for a HID device, there are the following requirements:
- must have an interrupt in endpoint to send periodic data to host
- must contain a class descriptor and at least one report descriptor
- must respond to the GET REPORT message
The following sections detail these requirements.
The first requirement for a USB device is that it must follow the USB enumeration process. The enumeration process begins when a USB device is plugged in and involves the sending and receiving of messages between the device and the host, which determine what the device is and how it works.
In order to correctly enumerate, a device must recognise the Get Descriptor message, and respond with its device descriptor and its configuration descriptor when these are requested. For a HID device, it must also recognise the Get Descriptor message when the report descriptor is requested.
As mentioned above, a USB device must provide certain descriptors and a HID device must provide some more. This section will describe each of these descriptors and illustrate using the default descriptors from the AVR-HID device.
The device descriptor is the main descriptor for the device. It contains information about which version of USB the device supports, the class and subclass of the device, the vendor and product id and the vendor and product name.
The configuration descriptor or descriptors describe configurations of the device. This includes power consumption, number of interfaces to the device, number of endpoints, device class and version, length of the report descriptor and descriptions of the endpoints present in the device.
The report descriptor describes the format of a report from the device. It contains the exact number of fields in the report, the format of each field and minimum and maximum values. This is the most important descriptor in the system, as it determines which information is sent and in which format. Also, an incorrect report descriptor will result in a device not being detected by the USB.
The format of a report descriptor is quite complex. For a detailed description of report descriptors and some tools for creating your own please see the HID page.
A control endpoint is used to send and receive messages between the USB device and the system. The system will send specific control messages along this endpoint and the device will reply along the endpoint.
The interrupt-in endpoint is where interrupts are received to indicate that the device should send its report data. The report data is then sent along this endpoint to the system. It is important that when the interrupt is received the data report is ready in the endpoint buffer. This means that your program should be constantly updating the endpoint buffer so that it is ready to be sent on receipt of the interrupt.
The device must also be able to respond to a GET REPORT message from the system. This message is sent at the end of the enumeration process but before the device is activated. It is used to ensure that the device sends the reports its report descriptor says it will send.
The AVR-HID project is still undergoing further development. This work includes adapting the circuit for use with smaller Atmel chips such as the ATtiny26, developing PCB layouts for the AVR-HID, developing a version which uses surface mount components to allow for a much smaller device and the development of a wireless version which makes use of RF transmitters and receivers.
Further information and updates are available from the project homepage.


Questions about if a certain Wifi adapter is compatible with the Aircrack-ng suite or what Wifi card is capable of packet injection and operating monitoring mode are commonly asked at discussion boards and social media. A Wifi adapter that is capable of packet injection and monitoring mode is trivial and important functionality to be successful in Wifi hacking.
Wireless packet injection is spoofing packets on a network to appear as if they are part of the regular network communication stream. Packet injection allows to intercept, disrupt and manipulate network communication.
|Wifi Adapter Packet Injection Test 2016|
An example of this is sending an authentication message from an unknown party outside the network to a connected client as if it was sent to the wireless router. This will result in the client disconnecting from the router.
Monitoring mode is one of the six modes a Wifi card can operate in which allows you to capture network packets without having to associate with the access point. If you are looking to buy a Wifi card which is capable of packet injection using the Aircrack-NG suite you can have a look at the following list of supported Wifi adapters:


viAct Listed in Top 100 Artificial Intelligence Blogs and Websites
We are really excited to be named one of the Top 100 Artificial Intelligence Blogs and Websites by Feedspot.com!
Being listed with the industry leaders Berkeley Artificial Intelligence Research, Massachusetts Institute of Technology, Microsoft, IBM, Google, Intel AI and MIT Technology Review is a big recognition that we greatly appreciate.
We will continue to work hard to provide helpful information to the #ConstructionIndustry in order to ensure safety, productivity and environment of construction jobsites with the help of Artificial Intelligence.
Read & subscribe our blog here for regular updates https://www.viact.ai/blog-1
#FeedSpot #AIBlogs #ArtificialIntelligence #VisionIntelligence #ConTech #ConstructionTechnology #ConstructionSafety #ConstructionProductivity #Top100AIBlogs #viAct


Electronic chemicals are chemicals used in the production of electronic components and devices. These chemicals are used to create the substrates, insulators, conductors, and other components necessary for electronic devices. Common electronic chemicals include etching acids, solvents, photoresists, fluxes, dielectrics, and adhesives.
According to the customer's personalized needs for electronic chemicals, we upgrade the existing products and production processes to meet customer needs.
Carry out in-depth matching with customers, comprehensively connect the packaging instructions and other aspects, and form a detailed product operation manual to facilitate the smooth operation of customers in the use process.


Antivirus technology has become an integral part of computer security. Computer viruses may spread in many ways, including email attachments and embedded code in the body of emails. They will also propagate via unpatched application weaknesses, file sharing solutions, and installing files. Malware software features programs that scan and remove any malicious code. The most effective antivirus programs have multiple layers of defense against viruses. Here are several of the most prevalent types of viruses:
Initial created in 1971, the first computer virus was the Creeper. This virus was a self-replicating computer virus that assaulted a device’s hard drive. This made it virtually unusable, however the concept of antivirus protection has become incredible. As more threats are made, the level of elegance of these goes for has also improved. In order to stay ahead of the competition, antivirus technology must develop. By incorporating https://globalwebreviews.org/avira-phantom-vpn-review/ these types of technologies, anti virus can preserve a computer system from the most up-to-date threats.
Antivirus software picks up and eliminates threats by simply checking data files and programs against a database of known malicious code. Nevertheless the software’s features are limited. New malware are challenging to detect and evade detection. Hackers understand how to circumvent antivirus security software software. Therefore, it is essential to update ant-virus software frequently to stay covered. Also to frequent virus removal, antivirus software will also find malicious application – just like viruses – on new systems. If a malevolent program can be detected, it can be automatically quarantined.


4500 HP | 720 RPM | 13,800 V Vertical Synchronous Pump Motors
Ideal Electric has built synchronous motors for over eighty years. Our expertise, combined with high quality materials and manufacturing processes, results in a reliable, cost-effective motor with high performance and low operating costs.
Synchronous motors are typically 1% to 2% more efficient than induction motors. This results in a substantial reduction in operating costs over the life of the motor.
Eliminate Demand Charges
Synchronous motors consume no reactive power, avoiding utility demand charges that are common with induction motors. A synchronous motor running at unity or leading power factor actually supplies reactive power back to the power system, improving the operations of a plant’s electrical system and reducing operating costs.
Many synchronous motors are designed with torque values greater than those specified in NEMA. Designing and manufacturing a motor to the application allows for trouble free operation without downtime and the high costs associated with loss of production.
Because synchronous motors typically have lower inrush current than induction motors, synchronous motors minimize the voltage dip on the power supply system when starting. This may eliminate the brown outs and resulting computer equipment shutdowns that can occur while starting large induction motors.
While running at synchronous speed there is zero slip. This increases the output of the driven equipment.
Quality materials and manufacturing techniques optimize stability and allow Ideal Electric motors to perform dependably under all conditions. Vibration problems are minimized with a very rigid frame construction, and by pre-balancing the rotor.
Rotor Shafts are forged high-quality steel. HIEC 4-pole designs use integral pole laminations that are bolted together under pressure before being shrunk-fit and keyed to the shaft. Typically on 6 thru 10 pole machines, the synchronous poles are dovetailed to the rotor hub. 12 pole and above are bolt-on pole style connected to a cylindrical hub.
Ideal Electric offers heavy-duty sleeve bearings as standard. Our bearing design can accommodate thrust, if required, and can be flood oil-lubricated or self-lubricated depending on the rating or application.
A variety of enclosures is available for every type of installation or classification including those that meet NEMA/IEC standards.
Sealed Insulation System
IDEAL offers full Class F insulation, epoxy VPI system, from our in-house VPI facility.
Brush type or Brushless
Excitation systems can be provided. The brushless exciter is mounted outboard of the bearings for easy maintenance. An adjustable DC power supply for the exciter field, pull-out protection, and incomplete sequence protection make IDEAL’s system unique. In addition, the slip and sensitivity adjustments are on the synchronizer rather than on the rotating assembly.
Ideal Electric can manufacture both vertical and horizontal synchronous motors ranging from 500 HP thru 50,000 HP with RPM 1800 and below. Supply voltages ranging from 400v thru 15,000v.
IDEAL manufactures motors to meet all current industry standards, including IEEE, NEMA, API and IEC. CSA labeling and ATEX/CENELEC approved designs are also available. IDEAL routinely designs motors for hazardous operation in Division 2 / Zone 2 environments.
Ideal Electric motors have been rigorously tested in our factory – and, more importantly, in the field – to ensure each motor is mechanically and electrically sound. Ideal Electric has responded to the demand for increased testing by adding a state-of-the-art test floor to our manufacturing facility. Our test floor allows for the full-load testing of vertical and horizontal synchronous motors at voltages from 480 volts to 13.8 kV and at 60 Hz and 50 Hz.


Research Informatics Programmer
Remo Williams joined DBHi in 2015 as a Research Informatics Programmer. In his role, he works with the Enterprise Informatics team on contributing to data driven application design around translational science projects. Remo's main focus is on the quickly growing national project, The Children’s Brain Tumor Tissue Consortium (CBTTC) and related data, specimen, genomic and imaging repository work . Remo has an incredibly extensive and diverse CV with 30 years of experience in the software development in industry and academia. Some highlights of his work include high performance computing relating to neuro-physiological experiments, development in AI and programmatic algorithmic approaches to analysis and applied decisions on spectral data for NASA and the JPL during his tenure at the University of Arizona. His software helped discover the most appropriate place to land a rover on Mars where there was a high likelihood of water. Remo recently spent 9 years in New Zealand as a software developer. Notably he was a developer at Codeshack, Ltd. He designed technologies around educational resources before moving back to the States with his family and joining Fidelity National Information Services (FIS). Remo holds a Bachelor of Science in Electrical Engineering from the University of Colorado and his Masters in Electrical and Computer Engineering from the University of Arizona.


Top 5 RF Radio Frequency Machine Suppliers
Are you in the market for an RF Radio Frequency machine? Look no further! With so many options out there, it can be overwhelming to choose the right supplier. But fear not, we’ve got you covered with our list of the top 5 RF Radio Frequency Machine suppliers. Not only will we provide you with a comprehensive guide on how to select a supplier, but we’ll also highlight the benefits of using RF machines and why they’re worth investing in. So sit back, relax, and let’s dive into this exciting world of radio frequency technology.
RF Radio Frequency Machine Suppliers
When it comes to selecting an RF Radio Frequency Machine supplier, there are a few essential factors to consider. First and foremost, you want to ensure that the supplier is reputable and has a solid track record of providing quality products.
Another crucial factor is the range of machines they offer. A good supplier should have RF Radio Frequency Machine a variety of options that cater to different needs and budgets. It’s also worth considering if they offer training or support in using their machines.
Price is always a factor when making any purchase, but it shouldn’t be the only consideration. Cheaper doesn’t necessarily mean better, so make sure you’re getting value for money with your purchase.
Ultimately, choosing the right supplier can make all the difference in your experience with RF Radio Frequency Machines. So take your time to research and compare suppliers before making any final decisions.
How to Select a RF Radio Frequency Machine Supplier
When selecting an RF radio frequency machine supplier, there are several factors to consider. First, it is essential to research and compare different suppliers before making a decision. Look for reviews and testimonials from previous customers to ensure you choose a reputable supplier.
Another important factor is the quality of the machines they offer. Choose a supplier who provides high-quality and durable machines that will last for years without requiring frequent repairs or replacements.
Additionally, consider the level of customer support offered by each supplier. Make sure that they provide adequate training and technical support so that you can effectively use your new RF radio frequency machine.
Take into account the price range of their machines and whether it aligns with your budget. Don’t forget to ask about any warranties or guarantees offered by the supplier in case something goes wrong with your machine.
By taking these factors into consideration when selecting an RF radio frequency machine supplier, you can confidently make an informed decision on which one best suits your needs.
The Benefits of RF Radio Frequency Machines
RF Radio Frequency Machines have become increasingly popular in recent years, and for good reason. These devices offer a range of benefits that make them appealing to both professionals and individuals looking to improve the look and feel of their skin.
One of the primary advantages of RF Radio Frequency Machines is their ability to stimulate collagen production. Collagen is an essential protein that keeps skin supple, firm, and youthful-looking. By promoting collagen growth through heat energy transfer, RF machines can help reduce wrinkles, fine lines, and sagging skin.
Another benefit is improved circulation in the treated area. The heat generated by RF machines helps enhance blood flow and oxygen delivery to cells in the targeted region. This increased circulation can RF Radio Frequency Machine lead to better overall health for your skin cells.
RF Radio Frequency Machines are also non-invasive compared to other forms of cosmetic treatments like surgery or injections. There’s no need for incisions or needles with these devices which makes them less risky than invasive procedures while still providing visible results.
RF technology offers long-lasting effects that can be seen after just one treatment session but continue over time as well with additional sessions scheduled according to individual needs every few months or so depending on your age bracket etcetera – making it a cost-effective solution!
Using an RF machine can provide numerous benefits such as improving collagen production leading towards more radiant youthful-looking skin while being non-invasive at affordable rates – all without any downtime!
The Top 5 RF Radio Frequency Machine Suppliers
When it comes to finding the best RF radio frequency machine supplier, there are numerous options available in the market. To help you make an informed decision, we have compiled a list of the top 5 RF radio frequency machine suppliers.
First on our list is Syneron Candela, a renowned brand that offers high-quality and innovative RF machines. With years of experience in the industry, their products are trusted by professionals worldwide.
Next up is Lumenis, known for its cutting-edge technology and advanced features. Their range of RF machines includes various models suitable for different treatments such as wrinkle reduction and skin tightening.
Third on our list is Alma Lasers, which has established itself as a leading supplier of aesthetic equipment globally. Their range of RF machines boasts impressive results and patient satisfaction rates across various treatment areas.
Fourth on our list is Venus Concept – another popular choice amongst professionals due to their state-of-the-art technology and user-friendly design. Their devices offer a unique combination of multi-polar radiofrequency (RF) with pulsed electromagnetic fields (PEMF).
Last but not least is Cutera – offering versatile and customizable solutions to target specific skin concerns through their highly-effective Radio Frequency devices that deliver excellent results.
These top five brands provide quality products alongside exceptional customer service- catering needs from professional clinics to personal use at home alike!
To sum up, RF radio frequency machines are an efficient and non-invasive way to treat a variety of skin conditions. They work by stimulating collagen production, promoting skin elasticity and firmness, reducing wrinkles and fine lines, tightening loose skin, and improving overall skin texture.
When selecting a supplier for your RF radio frequency machine needs, it’s important to consider factors such as product quality, customer service support, warranties or guarantees offered by the company. The top 5 RF radio frequency machine suppliers listed in this article have been thoroughly researched based on these criteria and come highly recommended.
Investing in an RF radio frequency machine is not only beneficial for personal use but also can be a lucrative business venture for beauty professionals looking to expand their services. With the right supplier providing high-quality machines and exceptional customer support, you’ll be able to provide clients with effective treatments that deliver noticeable results.
We hope this article has provided useful insights into the world of RF radio frequency machines as well as helped you identify some reliable suppliers to choose from. Get ready to elevate your skincare routine or business with the power of RF technology!


One of the most fundamental pillars of cybersecurity is cryptography, and most of the cryptography tools used today rely on computational assumptions, such as the difficulty of factoring 2048 bit numbers.
Two decades ago, we learned that the quantum paradigm implies that essentially all of the deployed public key cryptography will be completely broken by a quantum computer, and brute force attacks of symmetric ciphers can also be sped up significantly. Fortunately, quantum computers did not exist at the time.
Today, the wait-and-see approach is no longer a responsible option. Protecting against quantum risk takes many years of planning and deployment. The realistic timelines for evolving to a quantum-safe infrastructure are comparable to the timelines for the quantum risk to become a reality. If one is responsible for providing medium- or long-term confidentiality, the risk of waiting is even more acute.
Research advances in the past decade have brought security experts close to having a blueprint of a robust scalable quantum computing system, which will be followed by a focused engineering effort to build large-scale quantum computers. While it is hard to predict how long these final stages will take, there is no reason for people to be confident that it will take much more than a decade or so.
At present, I estimate a 1 in 7 chance of breaking RSA 2048 by 2026 and a 1 in 2 chance of breaking it by 2031. Recently, the US National Security Agency (NSA) announced preliminary plans for transitioning to quantum-resistant algorithms.
In my recent Journal article, “Cybersecurity in the Quantum World,” I explain quantum technologies and how they threaten cybersecurity. The article also discusses timelines for managing this quantum risk and the kinds of approaches an organization can take.
Read Michele Mosca’s recent Journal article:
“Cybersecurity in the Quantum World,” ISACA Journal, volume 5, 2015.
[ISACA Journal Blog]


by Chet Walters
RELAY BASICS - 101
Some may not know what a relay is or how it works. Maybe a little parable. There once was a little man named Jon whose job it was to lift a weight of 50 lbs. He could do this all day long with no trouble. But, one day the boss came up and said that Jon now had to lift 200 lbs. But Jon knew he could not lift 200 lbs without eventually breaking his poor little back. So, he got his friend, Hercules to lift the 200 lbs each time that Jon tapped him on the shoulder. So Jon was able to lift the extra weight through Hercules' strength and Jon did not have to lift any weight at all.
Let's say you want to add some extra horns to your truck. Your horn switch (Jon) was designed little but it only had to supply current (50 lbs) to your dinky little stock horn and can do that easily. However, your new horns are bigger and require more current (200 lbs). If you simply hook up the new horns to your existing wiring and switch, then your switch will burn out rather quickly. How to get around this? Install a relay (Hercules). A relay is a mechanical or solid state SWITCH which is triggered (tapped on the shoulder) by current supplied to its trigger terminal (86). When current hits that terminal it closes the switch inside the relay, be it mechanical (by energizing a coil magnet) or solid state (by tripping a transistor). The other terminals of the relay then feed current from the INPUT terminal (30/51) through the now closed contacts to the OUTPUT terminal (87). Your old horn switch does not feed current to your new horns, it only triggers the switch inside the relay. The switch inside the relay feeds current to your horns from a completely different source (ie battery). The wires to the relay triggers can be of very slight gauge (22-24) while the wire that actually work the accessory (in this case horns), can and should be of heavier gauge (18-10).
To wire up your new horns so that your little switch and slight gauge wires can work themsafely, wire them as illustrated. Your old horn wire that went "hot" when you pushed the horn button is hooked to the TRIGGER terminal (86). When you hit the horn button, the button only needs to supply a small amount of current to trigger your relay. Hook up heavier wire thru a fuse directly from the battery to the INPUT (IN) terminal (30/51) and then hook your new horns "hot" to the OUTPUT (OUT) terminal (87). Terminal 85 is common ground. Now, instead of asking your weak and EXPENSIVE horn switch to work the increased load, your strong, CHEAP and easily replaceable relay does all the heavy lifting.
Relays will also fail after a time. Some are even rated by the number of
times they will close a circuit before burning out (common relays are usually
rated to 100,000 operations). The advantage is that a relay is normally cheaper
and easier to replace than a switch.
|A common Bosch style
auto relay is shown above along with the functions of the terminals.
One should note that many relay packages are incorrectly labeled. The package that this relay came from labeled terminal 87a as "power to lamps" just like 87 when the 87a terminal is actually "normally on" and goes cold when the relay is triggered. One should test these terminals to determine what each actually does before making a permanent installation. Usually, if the center terminal is labeled ON THE RELAY as "87a" then it is usually a normally on terminal and will go hot (complete the circuit with terminal 30) when the trigger is cold. If it is also ON THE RELAY labeled as terminal "87" then it will usually be a normally off just like the outer 87 terminal. These 87 & 87a terminals can be used creatively as input to feed current from two sources to the 30 used as output. One should always mount a relay of this type with the terminals down and it helps to seal the seams around the case and terminals with silicone seal. These relays are sensitive to moisture and they will corrode if directly exposed.
|Another type of auto
relay (Conduct-tite #84607) is shown here.
One should test these terminals to determine what each actually does before making a permanent installation. Terminals on this three post relay are labled here with the functions of the terminals matched to the more common 4&5 post relay above. These terminals are not interchageable and the case provides the ground. This relay appears very similar to a typical auto horn relay, but most auto horn relay completes the ground circuit and is unusable in other applications. One should always mount a relay of this type with the terminals down and it helps to seal the seams around the case and terminals with silicone seal. These relays are sensitive to moisture and they will corrode if directly exposed.


In this time of an ongoing pandemic crisis, our team wants to address the possible community outbreak via contact spreading of the virus. If unaware virus carriers can be identified at the right time, we believe we can contain the spread.
What is it?
The FF Protect app is developed to help the community and authorities to detect and track encounters with potential COVID-19 carriers or patients. As we are aware it is becoming very challenging for the authorities and the community as a whole to create a route map and list of interacted people due to the nature of the disease where an infected person may be asymptomatic for up to 14 to 28 days and still could be transmitting the highly contagious disease.
Basically what it means is that you just need to install an app on your phone, and this talks with other nearby Bluetooth devices having this app and creates a map of people you have interacted with along with the duration. If someone gets infected, with this solution we can backtrack the people who they might have spread virus to.
How does it work?
- General public will install the FF protect app on the smartphone.
- Government affiliated health workers will input confirmed and suspected cases info in our web dashboard.
- Our server will process the above data and give basic insight to govt officials on our dashboard.
- Data scientists will access the anonymized raw data and extract scenario based insights and trackable information.
Our algorithm will decide and group people into the first level of contact that is direct, second and third level of indirect contacts as well. So that you and the authorities can take the necessary precaution. Please note that this is how various other countries claimed to have contained the spread, using technology to color code individuals and take necessary precautions. Together WE CAN MAKE A DIFFERENCE. These simple solutions will keep us safe in these crisis times and possibly avoid any community outbreak. Our team has made this entire solution open source, and we are ready to collaborate with the officials to deploy at large scale.
We had started working on this idea around a few weeks back. Initially, we brainstormed to use audio QR code technology which uses ultrasonic sounds to communicate between devices for the tracking, this technique has been used in many payment applications successfully. But we soon realized that the battery drain and the complexities involved with microphones and speakers we decided to look for alternatives. We found that most of the phones these days have Bluetooth Low Energy capabilities. BLE operates at considerably reduced power consumption while maintaining a large communication range. We quickly started building the prototype and found out that each phone can act as a beacon which emits low energy Bluetooth signals and at the same time scan for other Bluetooth signals. With Bluetooth low energy technology we can calculate the distance between users and also the duration of exposure to each other, it is capable of capturing the proximity of users up to a distance of 20 meters. As we launched the internal beta version, we read that Singapore launched a similar tracking system and was released in their country, but the Singapore solution was not made open source then. This gave us a boost and confidence to quickly built the production-ready solution and released it. Our apps background Bluetooth scan happens up every 30 seconds for a duration of 5 seconds. The battery consumption is only 2.5% drain every 12 hours.
The source code is open and is available on GitHub. github.com/FareFirst?q=ff-protect
Privacy / Security
- All user data leaving the user’s phone is transferred with a secure connection.
- Individual mobile phones receive only anonymized ids from the Bluetooth scans. These ids can be mapped only on the server.
- The server storing this data will be secure with all the govt mandated specifications.
- All the stored user data is encrypted.
- User installs FF Protect app
- Signs up with phone number
The app will automatically get activated and push encrypted data automatically.
Government authorities journey
- Enable user tracking in our dashboard whenever there is a suspected epidemic/pandemic scenario.
- This can be further tweaked to specific geographical areas only OR nationwide.
- Advanced filtering and conditional tracking options available, for example, people entering or exiting a particular geographical area. (this feature is under development)
- The data will get streamed and saved securely on the gov/private server.
- The health workers inform confirmed cases or a set of people to be tracked. The following info is to be entered in the dashboard.
- Phone number/s of index patient or suspected people.
- If phone number unavailable, then, Area of the of index patient or suspected people.(this feature is under development)
Data analyser/Data scientist journey
- Basic data analyzing and mapping will be provided by our system itself with predefined data processing algorithms.
- The anonymized data will be processed based on the health workers’ input and presented to the data scientist/s to analyze and predict the spread.
- The analyst can prepare reports and actionable insights by querying and processing the raw data.
- People identified with the virus are marked with Red color coding.
- After analyzing the proximity and duration of the contact, the data scientists report is generated, which will color-code individuals with various colors of different meaning. For example Yellow for direct contact, Blue for secondary contact, and Green for safe.
- This information along with guidance will reflect in the individuals’ smartphone, also the officials will receive this data for effective containment.
Together we can.
We are FareFirst and this our first step towards addressing a challenge in these difficult times. We strongly believe that we as a community can fight back and conquer COVID-19. We need to come together as a unit and break the chain.


How do I Disable the LED Light When Charging - YouTube... read more ›
How To Enable LED Notification Light In Android 6.0 Marshmallow... view details ›
How to switch off light on power bank - YouTube... read more ›
While in Settings, go to the General Section and hit the LED Blinker Activated button to uncheck it.... continue reading ›
How to Enable/Disable Red LED Light Indicator (Battery Charing) - YouTube... see more ›
Turning off or disabling LED Notification on Huawei P10:
Go to Settings. From the Settings, select “Sound &Notifications” Locate the option for the “LED indicator” Disable this feature using the toggle.... read more ›
How To Change LED Notification Colors On Android - Fliptroniks.com... read more ›
Many Samsung users say that reboot your system if your Samsung Galaxy s8 red light stays on. For that; Switch off your android device. Now press and hold 'Power and Volume Up' button at the same time.... see more ›
To change the colour, open the app, then go to the app's settings menu to find out which options are available. You can turn LED notifications on or off in the “Settings” menu.... read more ›
If you own an Android smartphone or tablet, you're likely familiar with your device's LED notification light. It's a way for Android to communicate information to you even when your screen is off.... view details ›
What to Know. On iPhone: Settings > General > Accessibility > turn on LED Flash for Alerts. On Android: Settings > Accessibility > Hearing > turn on Flash Notification.... read more ›
If the indicator light does not work, check the battery in your charger. It is common to replace dead batteries consistently as an easy solution to this problem. If you checked the fuse in your charger but the indicator is not turning on, then check the circuit board.... continue reading ›
Android TV™ models
- Select Device Preferences → LED Indicator → Operational response or Illumination LED → Off.
- Select Device Preferences → Illumination LED → Off.
- Select LED Indicator → Illumination LED → Illumination LED → Off.
- Select Illumination LED → Off.
Press the HOME button, then select [Settings] — [Device Preferences] — [LED indicator] — set [Illumination LED] to [Off], or disable [Operational response].... continue reading ›
In the Settings menu, scroll down until you see the “Display” entry, then tap that. A little way down this menu, you'll see a toggle for “Ambient Display.” Tap the slider to disable it. That will disable Ambient Display itself, which will prevent the display from waking every time you get a notifications.... view details ›
Samsung Galaxy S8: How to Enable / Disable LED Indicator Light... view details ›
Step 1. In the Settings menu, tap on Accessibility, then on Hearing. Step 2. Tap on Flash Notification and then tap on the toggle to activate the feature.... see more ›
Enable LED Notifications Light on Galaxy S10 & S10 Plus - YouTube... view details ›


A New Type of Neutron Star Observed
An international collaboration of scientists, led by Dr Manisha Caleb from the University of Sydney, has just announced the detection of an unusually slowly rotating neutron star emitting strange radio pulses.
One of the perks of discovery that excites astronomers most is when they stumble across something odd, weird and not fitting the regular models of what they were originally searching for. There are good reasons why these models exist - as many prior observations are refined through historical work to create data sets that feature baselines, regular parameters, and observable / testable phenomena - but that is not to say the outliers don’t pop up.
Sometimes the outliers can be far fetched - too good to be true, artefacts of instrumentation issues or the like. And sometimes, well, they can be remarkably interesting - with the potential to change our understanding of science, introduce new objects we never knew about, and even flip those models on their heads.
Today, a new paper has been published in Nature Astronomy by Dr Manisha Caleb from the University of Sydney which describes an outlier in the population of neutron stars - and it might be one of those cases that could change our understanding of this population across the Galaxy.
In the new article, Dr Caleb and her collaborators describe the strange new source they found as a neutron star giving off pulsed radio emission as it rotates once every 76 seconds. Pulsed radio signals from neutron stars is nothing new - an entire class of neutron stars exists known as pulsars (with the majority of the neutron star population observed being pulsars) - but none are known to rotate this slowly.
The discovery itself was somewhat serendipitous as Dr Caleb and her group used the MeerKAT radio telescope in South Africa (an array of 64 dishes, each 13.5-metres in diameter and spread over a larger region) to piggyback on observations being undertaken by another science group which was looking for different types of radio transients.
"Our data pipeline had originally identified this emission as radio frequency interference (RFI) due to its wide pulse duration, but luckily we always manually inspect the output," Dr Caleb told us.
The new object, named PSR J0901-4046, is somewhat weird when looking at the models of neutron stars. It is unlike the known pulsar population which have spin periods that start around 1.4 milliseconds and go up to 23.5 seconds. Nor is it just a regular neutron star, as it is emitting unique radio pulses, periodically. Its magnetic field is extremely powerful, about a quadrillion times that of your regular fridge magnet at home - giving some similarity to a handful of extremely magnetised objects known as Magnetars.
What makes this neutron star really special, is that its long rotation period and complex magnetic field structure seem to point toward a new type of object. Dr Caleb and her team think it could belong in a theorised class of objects known as the ‘ultra-long period magnetars” - of which only one other source, found using the Murchison Widefield Array, might be associated.
“Amazingly, we only detect radio emission from this source for 0.5% of its rotation period. This means that it is very fortuitous that the radio beam intersected with the Earth,” said Dr Caleb. “It is therefore likely that there are many more of these very slowly spinning sources in the Galaxy which has important implications for how neutron stars are born and age.”
PSR J0901-4046 is located in the constellation of Vela - an area of the sky that has been searched and catalogued over many decades in the radio regime - in fact, one of the most famous pulsars resides here (the Vela pulsar, and its associated supernova remnant). So how did this new object evade detection until this point in time?
It all came down to the way pulsar searches are conducted - often requiring astronomers to search for periods that they think the pulsar might be spinning in. And of course, according to the known population of pulsars so far, nothing really spins slower than 23.5 seconds. Until now.
“The majority of pulsar surveys do not search for periods this long and so we have no idea how many of these sources there might be,” said Dr Caleb. “In this case, the source was bright enough that we could detect the single pulses with the MeerTRAP instrument at MeerKAT.”
Evolving Compact Remnant Objects
Neutron stars exist because of the quirky quantum behaviour of subatomic particles. They form after supergiant stars, about 8 - 25 times more massive than our Sun, become unstable at the ends of their lives and explode as spectacular supernovae. During these events, the remaining stellar core falls inwards due to gravity, and the only thing preventing the core from total collapse is an effect known as neutron degeneracy pressure - which pushes the particles away from one another and prevents neutrons to be squeezed in any closer than a certain, limited configuration within a finite volume.
The rotation of these objects is the result of a shrinking radius that occurs during the core collapse event - where the progenitor star once used to be very big in size, it is remarkably small afterwards the supernova. This is a similar effect to seeing an ice skater spinning on the spot with their arms extended and then bringing them in - as they do, their rotational velocity increases. This means that the resulting neutron star contains approximately one to two times the mass of the Sun squeezed into about a millionth of the size - with most neutron stars being around 20 kilometres in diameter - making neutron star matter the densest material in the known universe.
Intense magnetic fields on the surfaces of these tightly packed objects tend to be upwards of 10 billion times the strength of Earth’s magnetic field and can accelerate electrons up towards the star’s magnetic poles (as well as other regions) to produce luminous radiation. This emission generally detected most prominently at radio wavelengths, often creates a pulse-like effect as the rotation of the neutron star shifts the direction of this radiative beam periodically; creating a lighthouse-style effect which is why astronomers term them ‘pulsars’.
Often, neutron stars and pulsars are referred to as one of the final evolutionary phases of massive main-sequence stars, and this is true - once these giants have exhausted their fuel reserves and undergone their supernovae events, they have transitioned into new, compact remnants.
But even neutron stars and pulsars evolve over time. For neutron stars, their surfaces cool down eventually, no longer emitting in the high-energy regime. In the case of pulsars, they lose angular velocity and their magnetic field levels subside, eventually falling below a threshold known as the ‘pulsar death line’ - where they are no longer capable of producing pulsed radio emissions due to the low magnetic field levels and slow spin periods. At this point, they just revert to becoming cooling neutron stars.
For some of these now ‘dead’ pulsars, who reside in binary pairs, they can have their angular velocity spun up again through the accretion of materials from their companions, as they evolve (these are a sub-class known as millisecond pulsars).
What makes J0901-4046 interesting is that it resides within the ‘pulsar graveyard zone’ - its spin is too slow to be doing what the other pulsars are doing - generating radio emissions. Unless of course, we are looking at an entirely new sub-class of neutron stars that have powerful magnetic fields but slow angular rotational velocities.
“The sensitivity that MeerKAT provides, combined with the sophisticated searching that was possible with MeerTRAP and an ability to make simultaneous images of the sky made this discovery possible. Even then it took an eagle eye to recognise it for something that was possibly a real source because it was so unusual looking!” said Dr Ian Heywood from the ThunderKAT team and the University of Oxford who collaborated on this study.
The Dawn of a New Population of Neutron Stars
Following the initial discovery and a review of the data, Dr Caleb set out to conduct follow-up observations to confirm the findings and the timing solution of this peculiar source, as well as other observations at different wavelengths, in the hopes that it might shed some light on this fascinating object.
At first, they observed with the MeerKAT radio telescope and later used the CSIRO Murriyang Parkes telescope to obtain precise timing measurements confirming the periodicity of the pulses that they had observed at radio wavelengths, and then additionally, they followed up using the space-based x-ray Swift Observatory to look for any detections at these frequencies. Unfortunately, none were found in this high-energy band.
However, the discovery of J0901-4046 does open up a range of new questions that has scientists excited - such as the possibility that many more of these types of objects exist across the Milky Way Galaxy which are not able to be seen from Earth due to their beams pointing away from our field of view.
Or maybe what we are finally observing is a missing link of the evolutionary phases of these compact objects, as they transition from magnetar to neutron star and pulsars or vice versa.
There’s even discussion that these objects might be linked to a relatively new, and yet not-fully-understood phenomena in radio astronomy - Fast Radio Bursts - with some theories suggesting these are generated by magnetars.
With this case now announced, further studies will hopefully find more of these objects, increasing the population that can be analysed by astrophysicists and revealing a little more about the outliers. Flipping the model on its head.
The paper is now available in the journal, Nature Astronomy