problem with Telefunken CR100

Autor

Beitrag

stevenrob
Neuling

#1 erstellt: 17. Dez 2016, 23:20

Hello, I'm a french people and sorry I speak Deutsch very, so I try English.

I have a problem with this boombox that I just buy.
When I plug it to AC and I put radio or cassette : the boombox works 5 seconds and stops. I Have changed the electrical transformer but no change. Have you an idea ?

Best regards

kadioram
Inventar

#2 erstellt: 18. Dez 2016, 12:57

Hi,

does it work when you use batteries (=DC)? If yes, you have probably a problem with your power supply (faulty soldering connections, broken rectifier diodes, worn out charging capacitors...)

If it won´t work with batteries, the variety of faults can be very wide spread...

I recently reworked a little "boombox" (not really "BOOM", a Sanyo ROBO), with the same fault. There had been some faulty soldering connection and worn out charging capacitors.

After resoldering and a complete recapping it worked again.

[Beitrag von kadioram am 18. Dez 2016, 13:05 bearbeitet]

stevenrob
Neuling

#3 erstellt: 19. Dez 2016, 00:55

Hello, you're right. With DC, all works fine. Could you show me with internet links the sort of resistor I must change ? I have the service manual but I'm novice in electronic.

Best regards

kadioram
Inventar

#4 erstellt: 21. Dez 2016, 15:44

Hello,
it would be helpful, if you could post some images of the circuit board.

You can order parts at

www.conrad.fr for example. The category is composants passifs

BR

[Beitrag von kadioram am 21. Dez 2016, 15:47 bearbeitet]

stevenrob
Neuling

#5 erstellt: 21. Dez 2016, 17:52

Hello,

I have changed 1,2 et 3 but no change. I will change the 4 (http://www.ebay.fr/itm/322180064215?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT).

Best regards

Rabia_sorda
Inventar

#6 erstellt: 21. Dez 2016, 23:02

Check the rectifier diodes, resistors and transistors in the power supply. The transistor (4) is a good idea.
At the power plug socket should be a switch which also check. Does the voltage at the secondary output of the transformer remain, or does it collapse?
Also look for bad solder joints.

[Beitrag von Rabia_sorda am 21. Dez 2016, 23:04 bearbeitet]

stevenrob
Neuling

#7 erstellt: 30. Dez 2016, 09:12

Hello, I have changed transistor number 4 and now the boombox works fine.

Thanks for your help guys

Best regards

Rabia_sorda
Inventar

#8 erstellt: 30. Dez 2016, 14:37

Fine!