Grundig A-9000 broken :(

[mat_one]

Hi.
I have bought broken Grundig A-9000. Have no idea how to repair it Maybe STK is dead? There is one burned resistor(RN13) on the main pcb.

I have service manual which can send to anyone who is intrested. Thanks in advance for any suggestions.

 

[ATRAC3]

Why don't you try if there is voltage on the speaker outputs? Does the relay turn on?

 

[mat_one]

there is no voltage. actually i`m pretty sure, the reason is STK. in free time `ll replace STK and i hope it `ll helps.

 

[mat_one]

relay doesn`t work (cant hear any sound like that)

 

[Zen Mod]

measure DC on outputs before relay ;

if it's present , there is just slight chance that STK isn't shot

 

[mat_one]

thank for clue. soon `ll check it and type the result.

 

[gmphadte]

Measure input pins' voltages
If both measure nearly same, then the STK is good.
If u find this voltage is not close to zero, then check the resistor powering the input circuitry of the chip (will be around 100 ohms). This may be open.

Gajanan Phadte

 

[ATRAC3]

I guess that if the relay doesn't click (turn on) the STK is dead so the protection curcuit doesn't turn on the relay to protect the speakers. Or maybe the resistor that's burned was powering the protection curcuit and now it dowesn't power the relay... Anyway send me the manual to check it out

 

[mat_one]

Very thanks for all tips guys.
Actually i have no time to check all these options, but maybe firstly i should check the TP (Test Points to current idle) if there is any voltage. That ll be fast one. If there is voltage the reason should be STK.

Resistor on pic is burned, so i have to replace it. when solder it out, will check if it has connection between two ends. then one option ll be checked.

The scheme is available here: http://m2.xt.pl/grundigfineartsa9000.zip

 

[kissn73]

Hi everybody!

Mat_one, you have written, you have the service manual (I think not only the schematic) for the Grundig A9000. If it is still available plese send it to my E-mail, or plese send a link where from I can download it. I have an A-9000 too, but it hase several errorrs. Without the service manual I can not repair. Only the shematic is not enough, because I have to check -for example the bias- in the power amplifier part.

Thank you for advance!
Best regards
Norbert