AudioSource AMP200 - help needed

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
hi everyone,
my AudioSource AMP200 stopped working yesterday. I was listening @low volume and it just stopped. I pushed the power button and I heard a pop. Opened it.
The fuse is fine but a 104 ceramic cap smoked. it is located on the power board. can't find the schematics anywhere -as far as i can tell, the same schematics are used by a few different manufacturers (audiosource, OSD audio, etc) and the board is the same for the AMP200 and AMP300.

I replaced that capacitor. the amp still doesn't power up. so far I managed to measure some voltages coming from the transformer and it seems fine. the wires that go to the amp/preamp are labeled (15V, 24V, power, etc) and it seems the voltages here are zero or too low.

any advice or schematics would help me, thanks for your time, have a nice day!



*as seen in the pic
1- cap 104 replaced
2- AC is coming from the transformer
3- NO AC or DC voltage
4- i don't remember right now

*some heat coloration can be seen on the back of the power board, marked it in the pic

*2 more pics for whoever is courious how the inside of a AudioSource AMP200 looks like. I had a hard time finding any pics so I'm posting some....

An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.
 
IC01 and IC02 seem to be completely desoldered from the board
and the electronics around this group is burned, that's why you can't get
a reading on output 15 and 24 V. Get the whole power board out and
check all the parts. What's the code of the IC's?
 
@Lojzek
thanks for your reply

kia 7815a (IC01) and 7915pi(IC02)

I am unable to find any shorts so far, and all the resistors show some value... except the R01 and R02 don't show any reading when measured for resistance.
brown/black/gold/gold/space/white probably 1 Ohm 5%.

*I just saw some pics of a AMP300 and it had the same coloration on the board, more pronounced and I think it has to do w/ the resistors and also 7815 and 7915 have PIN2 connected to the heat sink as I recall reading.
 
I measured the transformer by itself Power Board disconnected
[big connectors blue,blue,back]
AC-A + G =38ACV
AC-B + G =38ACV
AC-A + AC-B =76 ACV

[small connector brown,black,brown]
5=G
5+4=22ACV
5+6=22ACV
4+6=44ACV

the resistors R01 &02 are open (pic 2 low-right). the relay is open.
the bridge rectifiers are not shorted out.
 
So, the transformer is healthy. If R01/R02 are really a 1 ohm resistor,
bypass these with another 1 ohm to see what happens.

Open circuit would suggest that these are toasted.

Can you confirm the resistance of the relay coil?

I haven't studied the layout to make the schematic out of it but
the relay should be energized with Vdc. Make sure that you
have that voltage available.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.