Uher Z124 charger

[esla]

It's the same as here - and shold be allright. The contact with the question mark, is in the diode bridge, but the fifth diode! Have a look at the schematic, there we have the four diodes für the "Graetz-Gleichrichterbrücke". But on the left upperside you'll find a fifth diode - and that ist this pin. Therefore the wire goes directly to the negative side of the capicator C5.

The wire from the pin 8 (green with black bars) were soldered to the point marked with "?" in the pic, and measuring that "?" point between any other of the diode bridge, the impedance is always null, if I measure as a diode, that point againts any other of the diode bride, is always null too... so, is like that point went to nowhere.

That can't be! If you are measuring "null" ohms, this diode is out of order. Replace the diode bridge and for these diode in the upper left try to solder a external diode. I've measured in the "Ohm"-Range always over 1 kOhm here from this pin to all other pins of this diode bridge. And she ist soldered. Or, try to replace only this diode, may be it works also. solder the green wire with black bars with the anode of a 1N4001 or so, and the cathode with Pin 1 of the the transformer (schema posted by Hans-Joachim). You must have 15 V over the "C5". It is only a, how can I tell it, a simply "help-voltage". But it must be there.



Greetings Jens