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Harman Kardon 630 ?

I did the hum injection and had no hum at the resistors R320 and R321. I did at the other test points. So I will get some of those 1uf 50 v caps and replace them.
My dim bulb lights up again when I turn it on. So I cycle the power switch and I disengage the speaker switch and re-engage it a couple times and it works. Then it will play fine for hours.
Any ideas? Transistors weak?
I really like the sound of this receiver and it is so clean.
 
I did a couple experiments First I tried a different speaker and wire. I had the same result. 8 ohm speakers, then tried my Kef C15 4 ohms. It didnt light the Dim Bulb. ?
I noticed it was bright as soon as I powered it up then dims and almost goes out then comes back up brighter again. Occasionally it will not light the DBT.
Experiment 2 power up speakers switches not engaged. engage speakers DB lights up.
Based on what I saw before I powered up and waited the count of ten. It does not light the dim bulb tester when I do this, I repeated several times.
First I had tried 5 seconds not enough time. Ten seconds seems to allow the voltages to level out
I don't know what to look at next or where?
 
Without the dim bulb adjust your amplifier(s) idle current ( bias )...
 
Decided to take it one step further. Connected speakers to "A" terminals, connected the voltmeter to "B" terminal.
At power up I see 27 vdc that bleeds down to 0 vdc.
 
I only have the dim bulb tester and my meter.
The manual says to connect a 50 ohm resistor to the Lt speaker and then connect the O-scope and a signal generator. I dont have any of this .
Is there any way to do it without them?
I see the VR621 and VR601. Should I hit them with deoxit and clean them first?
 
Read step 5 last sentence of the predrive/driver adjustment for option 2 for adjusting idling.
 
I guess I dont understand where to connect the leads I connected the red lead to the resistor wire and the black to the frame I don't get much change when adjusting 601 should the black lead be somewhere else? Like -32v or on the other end/side off the resistor? Across R617?
 
Done. I appreciate your patience with me.
I figured out what Measure across means and now have 10mv across R 617 and 637
Thanks again for your help.
I found the power regulator board has evidence of heating At R802,R805,R804 area. Do you have any advice for it?
1B788409-53DB-494E-B168-2EC25A0B7221.jpeg
I have the caps ordered for the fm mpx board.
 
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