XX-Rare engraved 2215 damaged in transit ; Again ... (2nd smashed for me)

I believe that the gain (hfe) of H705/H707 (R channel pair) as well as H706/H708 (L channel pair) and need to be matched also, but please verify this with someone else.
 
I mentioned your statement to my supplier coz he is tech as well, and he said that he will dive in and check out by the code(model) and specs of transistor also.
Thanks for your input btw.

I run out of bipin leds so I adjust peacelovemusics dial led for stereo light. Works like a charm.
Lucky the stereo gap is wide enough.
Regards.

IMG_20240611_134934.jpg
 
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My ordinary supplier couldn t get me those transistors so I google a day and finally ordered from Mouser for the first time.
All and some additional stuff was delivered superfast. I am in EU an I placed order in monday, and today (thursday)I have all the stuff on the bench.
Just in 4 days!!!! That s awesome and superb.
And It is quite like someone else said: Its like christmas when Mouser come to house...indeed.
Happy.IMG_20240704_154636.jpg
 
So I replaced all caps and transistors on amp board. H701,702 ksc945 ; H703,704 BD139 ; H705,706 ksc945cyta ; H707,708 ksa1013yta

Still no luck , distortion right channel.
I bought main caps and I try to figure it out how to properly solder the four wires coz it is snap in version. Should I just wrap the wires around the pin
and solder all together?
BTW I solved BD139 with mechanical engineering elegance... :)

IMG_20240711_173703.jpg
 
Guess this isn t my lucky day afterall...
So, powerboard is new, amp board almost, big filter and caps replaced, tone board could be suspect also.

There are old caps on that tone board. Only complete set of transistors were replaced.

How about outputs? Could they distort a channel?IMG_20240711_204345.jpg
 
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OK, that should be close to 0V with no signal. (EDIT: See post #39... it's not 0v) I don't see voltages on my schematic so what I would do is measure each transistor EBC voltage on the good channel then compare it to the bad channel to isolate where the voltage goes bad. Start at H701/H702 and work down the circuit to the output. Could be a bad cap somewhere.
 
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By the way, it looks like the schematic has mislabeled H710/H711. (See P700 board layout) Odd numbers = Right, even numbers = Left.
Measure each transistor DCV, with no signal input, on both L & R channels and compare until you find the difference.
Also, please double-check the replacement transistor EBC pin outs and electrolytic capacitor polarity to make sure they are OK.

1720730286856.png
2215 P700 Schematic:
1720730579729.png
2220 P700 schematic. It looks very similar to yours except for a couple of transistors. Maybe this will help.
It does have voltages for each transistor. See if they match up with yours.
NOTE: I was incorrect in saying that the voltage that you measured on J716 was supposed to be 0v.
1720737635070.png
 
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Well I measured the voltages on transistors. Measurments below. I triple checked for soldering failure but it's almost impossible to get it wrong because I solder one component at a time regardless of the silkscreen. Always watching the original instaled components. (If she is a virgin of course lol)
H709-H712 are old one and not been replaced.

E B C E B C
H701 0,149 0,762 24,78 H702 0,145 0,751 24,79
H703 0,820 0,809 1,530 H704 12,20 12,14 12,97
H705 2,346 2,462 3,610 H706 15,81 16,62 15,79
H707 2,346 2,308 1,515 H708 15,81 15,23 15,79
H709 3,049 3,616 37,00 H710 36,55 36,75 14,86
H711 2,137 1,515 0,662 H712 0,004 12,90 0,001

As you can see, there are already big discrepancies in the second item, but since I am not a tech I don't know what they mean.
The fact that the right channel is not working as it should is obvious.

Regards
ps
measured trough dbt
 
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