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Kenwood KA-7100 help

I removed Q33 and tried the amp to see if I hear the click of the relay, no luck.

When I test the outer legs of the diode I get .848

When I test middle I get .838
 
with qe33 still removed put your meter on ohms and check re83 56k . and re84 33k these can be left in circuit to test . if those test good pull out ce40 and power up . relay should click instantly if ce40 was the culprit .
 
Today I cleaned up the bottom of the main board, it was terribly dirty and I hoped it might help.

I couldn't get a very good reading with r83 and r84 on the board so I pulled them and they test correctly.

I pulled the c40 capacitor and still had no luck getting the relay to click.

Do you think it could be the relay itself that's bad?
 
Yes, both r83 and r84 are back on the board.

R83 reads 25 when on the board but read 55 when off the board.

R84 reads 22 on the board and 29 when off the board.
 
I'm so sorry! I read that as soon as I rolled out of bed this morning and apparently didn't pay too much attention...

R83 reads 46v DC on one side 0v on the other.
R84 read 0v on both sides
 
measure voltages at the line end/banded end . better known as cathode . de15 de16 .

so black lead to chassis again meter on dc volts . red to each cathode in turn .
 
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pull out ce41 and power up and see if relay clicks .
if it doesnt it looks like its time to pull and test qe34 for short between base and emitter .
this is fairly uncommon .
thing thats bothering me is the zero volt readings as i would expect to see at least a few millivolts
.
 
I tried d15 and d16 again with a lower setting on the meter and got 1.34 volts on the cathode side for both. I'm sorry for the confusion, I'm still learning/ getting used to this meter.

I will pull c41 in a bit and report back
 
I pulled c41 and still got no click from the relay.

I then pulled q34 and I believe it tests good (if I am testing it right....)
 
put the parts that you took out back in .
then you need 3 hands . so clip your black meter lead into the speaker negative/ black left channel .or to chassis if you can .it doesn't matter which .
hold red meter lead onto the re79 on the side that reads 390mv and turn vre1 very slowly and see if you can get meter reading 0v dc .
hopefully relay will click . even if it doesn't and you can get it close to 0mv its a step in the right direction as it needs addressing anyway .
 
@ petehall - You are doing a great job troubleshooting. I scanned the thread once and did not see whether you guys have checked the power indicator LED itself? Not trying to butt in, just thought that maybe this is an unusual circuit arrangement and possibly it hadn't been checked. Apologies if I missed it in the previous posts...
http://www.audiokarma.org/forums/in...a-7100-part-of-the-protection-circuit.384636/
http://www.audiokarma.org/forums/in...a-7100-part-of-the-protection-circuit.384636/
 
Good looking out Roger2, this sounds very similar to my situation.

How do I test the LED and where is a good place to get a new one online?
 
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