text: nomadpete - Recreational Flying
  nomadpete last won the day on May 26 2015
  nomadpete had the most liked content!
  About nomadpete
  nomadpete replied to Old Koreelah's topic in Instruments, Radios and Electronics
  The "crowbar" is simply like a switch in between the alternator supply and the battery. (There are two types of scr regulator, the most common is series type) When the regulator senses 14.2volts at the battery, it open circuits the path. In that way, it functions as a simple "overvoltage cutout". When this happens, your electrics are expected to run off the battery. The big electrolytic capacitor (as recommended by Rotax, not sure if Jab have), is important to smooth out the spikes that the regulator produces as it transitions from "switch closed" (direct connection between alternator and battery), and "switch open", (fully charged). That phase is characterised by continuous short spikes of full charge voltage. None of these circuits I have seen are capable of providing any charge unless the battery voltage falls below a threshold. Usually internally fixed at about 14.2 volts.
  Apr 18, 2019 09:43 PM
  Having said all the above, I feel that you have a wiring problem, rather than a regulator one. After all, the regulator shouldn't cause total loss of electrics.
  Apr 18, 2019 06:15 AM
  OK, Your jab alternator is indeed an AC device. However I point out that the Jab regulator is not what one would call "automotive' type. Maybe motorcycle type. It has no form of current regulation, and due to the lithium battery having a amazingly low internal resistance, it is quite possible that the Jab alternator/regulator combination is overloaded during climb out. After all, the battery has just discharged significantly during cranking, the motor is running at high rpm, so the alternator is putting out max power,and the regulator won't be cutting out until battery voltage reaches its fully charged voltage. Until then, the battery will be fully loading (maybe overloading) the charging system. In the absence of a ammeter, you can't prove or disprove my theory. This is the 'problem' when using a lithium battery in a system that was designed for a different kind of battery. It needs a regulator that limits the voltage and the current. I am not aware of any. BTW, this applies equally to Rotax, as they have a crude Ducati system similar to Jab.
  Apr 18, 2019 06:10 AM
  nomadpete replied to red750's topic in Aircraft Incidents and Accidents
  At last! The media gets it RIGHT. It actually is a Cessna! Well done. Great landing, although the local plod called it "he did fairly well". Faint praise indeed.
  Apr 18, 2019 05:41 AM
  Apr 11, 2019 05:10 AM
  I'd be closely examining the earth path all the way from engine to battery to load. Maybe the torque from the engine at max power is moving a part of the cabling, and when you ease back on power it flexes part part of wiring a little less. I've experienced that sort of problem in a motor vehicle. Very intermittent and mostly when the motor was under heavy load.
  Apr 08, 2019 01:05 AM
  We are going to the moon people!
  nomadpete replied to fly_tornado's topic in AUS/NZ General Discussion
  Ben Elton probably didn't think his plot was likely to ever eventuate. But maybe he had a Arthur Clark moment when he wrote it.
  Mar 01, 2019 12:16 PM
  nomadpete replied to Garfly's topic in AUS/NZ General Discussion
  Feb 26, 2019 05:32 AM
  nomadpete replied to farri's topic in Drifter
  Of course Tasmania is warm. Its got central heating from all those fires. We had to burn 150,000 hectares of firewood to get our temps up above 30. We try to do this every summer to keep the mainland tourists warm. It'll all have to end 'cos we are running out of forest.
  Feb 02, 2019 09:54 PM
  nomadpete replied to NT5224's topic in Governing Bodies
  And what if a 'quiet word' fails to achieve cohesion within the board? Does that mean the chairman has failed and must step down? That would only empower the disruptive individual (if, indeed he/she is disruptive - in their own mind that are not). It can be difficult to bring any bunch of people together with a common goal. Our Board members do not get to choose their fellow board members.
  Jan 26, 2019 04:33 AM
  nomadpete replied to old man emu's topic in Aircraft General Discussion
  So true. Isn't that a sad illustration of what is happening to the pursuit of recreational aviating in Australia!
  Jan 19, 2019 09:45 PM
  OK We've done this drift to death. We all have horror road stories. We all have strong ideas on how to fix the problem. The answer is......... Human factors training. Advanced defensive driver training. And remove the automatic RIGHT to drive. End of story
  Jan 16, 2019 08:09 AM
  Coopers Gap Wind Farm Construction
  nomadpete replied to JG3's topic in Trips/Events/Seats
  I was at Tarong PS when it was being built, and many many times over the years. Initially the electrostatic precipitators were great at removing particulate content from the stacks (it's a 4 in 1 stack - 4 boilers, 4 turbines). Early on there was no sign of smoke. Over the years, the quality of coal got worse, maybe more dirt as you dig deeper? They tried trucking coal from Acland and that burned better but it was hard coal - you should have heard the racket from the ball mills trying to pulverised it! (They burn coal dust in the furnace) So back to using dirtier than usual coal. I was told that those cooling towers use 80 megalitres a day. Not good in a drought. The other stack is the newer Tarong North power station. I don't know why but it doesn't smoke.
  Jan 16, 2019 03:08 AM
  nomadpete replied to bexrbetter's topic in Aircraft Building and Design Discussion
  Welcome back Bex. Take it easy. Please. Give yourself time before trying to be too active. I know inactivity will drive you nuts (it did me, though nobody can see the difference). But is important to your recovery phase.
  Jan 14, 2019 06:54 AM
  Hi Bex. By the time you read this you will be back with us. If I'd seen your post before you went under, I would have been able to offer you some reassurance about your big adventure. Well, that is what I called it when I went through a similar mitral valve repair last year. Its a sobering thought to know that someone will be literally holding your heart in their hand. In my case they stopped my heart for almost 4hrs, as there was a bit of extra work they had to do while they were in there. Or maybe the surgeon just wanted to trade his Bremer in on a new Tesla. They did warn me that when i wake up, to expect to feel like I'd been hit by a bus. Glad they warned me otherwise I'd have been worried about what they fluffed up! Anyhow, it's all worth the journey. Now I've got back the energy I used to have. Enjoy your new lease of life!