Next restoration: Yamaha PC2602M

A possible distribution could be this:

Input board:
C311-312 / C301-302 (input caps): Nichicon ES
C317-318 / C307-308 (PS filter caps): Nichicon KZ

Amp board:
C102-103 / C202-203 (Input and feedback capacitor): Nichicon ES
C107 / C207: Nichicon KZ
PS filter caps: Nichicon KZ

Power supply:
Nichicon HE (105ºC, low ESR)​

Note: KZ caps are bigger than originals. FG series fits better by size.

Edited cap types
 
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Are you planning on replacing the big filter caps? I priced them a while ago and they are way more than I paid for the amp EACH, wow.

I don't think you can go wrong with any of the caps you listed. I usually go ES for bipolar and KZ, FG and maybe Silmic2 for audio path and Nichicon KL for low leakage. Power supply caps I tend to go Nichicon PW or PM as recommended by Avionic (somewhere, at some time) though I've heard a lot of people have great results with Panasonics.
 
I usually go ES for bipolar and KZ, FG and maybe Silmic2 for audio path and Nichicon KL for low leakage.

What are you using for the caps outside the audio path in the amp board? I've had great results with Panasonic FM, but they are only rated to 50V.
By the way, most of the original caps are ELNA duorex, including the power supply board.
 
I usually for with Nichicon PM or PW but I haven't gone through the 2602 yet so I am not sure they will have the needed ratings.
I did notice all the Duorex in there but haven't checked if they are available or not either.
 
That would be great actually. I always end up missing a cap or two when going through an amp, it would be great to have a known good list to run by.
Thanks very much.
 
New parts have just arrived!

IMG_8479.JPG

On the other hand, the chassis begins to be clean and shiny...

IMG_8484.JPG
 
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About the bias adjustment.. I was unable to find the factory value. I think that a value between 20-50mA could be a good starting point.
 
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Mine is working well so I can check the bias to give a known good starting point if you like.
It's really strange that the PC2002 manual has a pretty detailed section on all of the adjustments but this manual doesn't.
 
It would be nice. A friend of mine has the little brother, PC1602, and he is also going to check the bias
 
I'll pull it out and get the bias measured. I tried once using those test points but never did get anything resembling what a bias reading should be so I'll just clip the leads to one of the emmiter resistors on each channel.
There was a mint one owner 1602 for sale for $50 on CL a few weeks ago that I thought really hard about buying. If it wasn't a 300 mile round trip I would have gone for it. If it was a 2602 in that condition for anywhere near that price I would have taken a half day at work and been flying up the freeway for sure.
 
What do you think about using Nichicon HE instead of KZ/FG for DC filter on the amp board? C119-120 (47/100) for VAS, and C130-131 (470/100) for power.
 
I'll pull it out and get the bias measured. I tried once using those test points but never did get anything resembling what a bias reading should be so I'll just clip the leads to one of the emmiter resistors on each channel.

My friend have just measured it using the test points.

S - (+): 1.8mV
S - (-): -1.6mV

It's a very low reading...it doesn't make much sense as a bias voltage.
 
That's about what I got when going from those points as well. I had a thread about it and we all pretty much were scratching our heads. I'll pull it out this week and clip it to the emmiter resistors and see how it compares to the test points.
 
I went ahead rechecked the bias voltage using the test points and started with 0mV at startup which slowly crept up to around 4mV on each channel after about 20 minutes. It didn't seem right but does correspond somewhat to what your friend showed and what I measured before.
I went ahead and pulled the side cover off and clipped my test leads directly across an emmiter resistor on channel 2 and got much the same measurement.

I guess these are biased really, really low from the factory. Next time I have it in the system I might try going up to around 10mV just to see if it sounds any better/different.
 
Amp board:

- Cleaned
- New caps
- New trimpot
- New relay
- New drivers
- I haven't changed the output transistors yet

IMG_8712.JPG

Input board:

- Cleaned
- New caps

IMG_8710.JPG
 
I have had one myself for sometime and only occasionally does it get used, it never gets more than slightly warm and the fan has never come on.
It runs a pair of Watkins woofers in some Infinity's or a pair of EV 15" woofers.
 
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