Service Manual for GRUNDIG T-55 370/5

 

What do you want to know about it?, I should have a paper manual at work - but I need the CUC number off the back to find it!.

__________________
PIC programmer software, and PIC Tutorials at:
http://www.winpicprog.co.uk

 

i have this tv model and it doesn't work for a few months. it's my grandfather's tv. i'm new on tv repairment and i study on it. so, i said that it is a reason to make my first steps knowing of course about the dangers. So, i asked if i can find just easy a service book for this model to start my "experiments". If you can help me i can find the CUC number when i'll go to the village, because i supposed that the tv model was enough. what is the CUC number Nigel? C.... U.... C..... ?
thanks.

 

CUC is 'Compact Universal Chassis', it's the chassis number of the set, it's on the back near the model number, it should be CUC followed by four digits.

__________________
PIC programmer software, and PIC Tutorials at:
http://www.winpicprog.co.uk

 

Sorry Nigel, the model is: T-55 730/5 and
the CUC is: 7301
I find and another number, i don't known if it is useful to you, here is:
GCA 47

 

CUC7301 is the number I need.

So what's wrong with the set?.

Assuming it's dead?, it's a VERY common problem, caused by a dry joint on C669. This cause the PSU to 'blow up' requiring a substantial rebuild, chip, transistor, six diodes, one zener, three resistors - and occasionally other bits as well!.

__________________
PIC programmer software, and PIC Tutorials at:
http://www.winpicprog.co.uk

 

Yes it's dead. I want to measure the PSU but first i want to ask you first. Is there any service manual to attach me, because i want to known where i will measure. if you are sure about this problem show me only the PSU circuit with some voltages so i can know what i'm doing. C669 is a capacitor or something else? Don't laugh, i don't known very well about the numbers of some special tv components. As i remember this tv had another problem at the past and fixed by a technician, but after a month the tv was dead. The power led is off when i turn on the tv.
Thanks for helping me.

 

C669 is a capacitor, it's close to the switch-mode mains TX, and it's almost certainly blue.

You should also be VERY aware that the main electrolytic usually remains charged when the PSU dies! - it can give you quite a nasty shock!.

For a start, check if the switching transistor is S/C, it's the one on the heatsink.

__________________
PIC programmer software, and PIC Tutorials at:
http://www.winpicprog.co.uk

 

Ok Nigel. i know about switch-mode PSU's because i constructed one at the past, for my lab. if i'll see a problem i'll tell you. thanks again!

 

And something else. I posted a topic to "Microcontrollers". "Problem with RF connection" is the subject. The problem that i had, i posted it at the past again and you give an advise. Can you, please see the post to give me an opinion, as i give more details for the problem?