the basic module 10 shown in fig1 has a housing section 12 in which electronics for connection to a power line supply are accommodated . the housing section 12 is adjoined by a bay 18 into which a stationary power source 24 ( fig2 ) or a mobile power source 30 ( fig3 ) can be inserted from above . on the underside of the power source 30 , terminals 36 ( fig5 ) are provided which can be stuck onto corresponding terminals on the bottom of the bay 18 in order to establish a connection of the power source 30 for supplying the charging power . in addition , a socket 37 is provided for connecting a plug - in transformer if the power source 30 is not used together with the basic module 10 . the housing section 12 and the bay 18 extend towards the top from a level bottom area 14 . on the front end face 20 of the bay 18 , a flap element 22 can be swiveled towards the bottom about a horizontal axis from the closed position shown in fig1 , in which it is flush with the end face 20 , into the suspended position shown in fig6 about a horizontal swiveling axis , which adjoins the bottom area 14 . when the flap element 22 is in the suspended position shown in fig6 , a holding element 44 can be pushed onto the flap element ( see fig8 ), which has at its outer end facing away from the end face 20 a holding projection 46 extending towards the top . the holding projection 46 prevents a device suspended on the flap element 22 , such as , for example , a head band , from slipping away . at the end of the flap element 22 located adjoining the end face 20 , a switching element ( not shown ) is provided which interrupts the connection between the respective power source 24 and 30 , and a connected load when a pressure is exerted from the top onto the flap element 22 located in the suspended position . as can be seen in fig7 , a connection 28 for a power supply for an illuminating device and a rotatable control knob 26 of a control device ( not shown ) for the brightness of an illuminating device is provided on the top of the stationary power source 24 . in addition , there is an operating status indicator 38 . instead of the operating status indicator 38 , the mobile power source 30 has a number of charge control lamps 34 . inside the power sources 24 and 30 , respectively , active control electronics are provided which can remotely control the operating state of the power source 24 and 30 , respectively , including the output voltage , status indicators and operating functions , inter alia . the control signals can be wirelessly transmitted from the control unit . it is also possible to transmit the control signals via an additional control line or via the same feed line by means of which the operating power is transmitted . the control knob 26 is connected to a control device ( not shown ) which controls the current for adjusting the brightness in a led . during operation with an incandescent lamp , control is effected by adjusting the output voltage . in a preferred embodiment , the control device has two operating states . in the first operating state for controlling the brightness of an incandescent lamp , the control device is active on the respective power source and the output signal of the power source can be controlled ( duty ratio of the pwm signal ). in the second operating state , the controller on the power source is deactivated . the output signal on the power source can then no longer be controlled . in the second operating state , control can be effected by an external controller which can be mounted , for example , on a headband on which an illuminating device with led is mounted . the first operating state is caused or determined when an incandescent lamp is used . when a led is used , the second operating state is selected .
a power source device for diagnostic instruments is adapted for a connection of different types of illuminating devices and includes an active control unit for controlling an operating state of a power source in dependence on a type of a connected one of the illuminating devices .