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Accuphase Help...

drmike

drmike

New Member
Hello dear members,

First of all, I want to apologize for my English
I live in France and I restore vintage HIFI for many years (for my own)
(Here are some Youtube links
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)
YouTube
YouTube
YouTube
YouTube

I had the opportunity to buy recently in Japan an Accuphase P-300S
I have already restored an Accuphase P-300 but the version "S" is different
I can not find anywhere the schématics and service manual on the internet (for adjustment points, BIAS, DC offset etc ...)
Please, can someone help me?
with many thanks

Alain
 
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Unfortunately accuphase doesn't share tech info . Only authorized service locations have access to the documentation.
I'm not saying no one has it , but I've seen several threads where people have been looking without luck.
Have you tried contacting accuphase directly?
Good luck
 
Hello,
Yes, I sent a mail to Accuphase Japan, they redirected me to the local distributor here in France who answered me "yes, I can send you a copy for 50 dollars"...
I found it a bit expensive for a PDF file!!...(note that the P-300 user manual is easily and freely available on the internet)
That's the reason for my post!
Thank's anyway
Alain
 
I had an Accuphase P300S and the manual for the P300 was substantially similar enough for me to do some serious work on it, including calibration.

Hopefully your protect circuit is working OK, as the analog IC in these usually fail.

Contact Rick at Stereomanuals.com - it will still cost - but a bit less than what Accuphase would charge.

I think Rick will only mail a hardcopy to you as well - thats how I got my manual from him.
 
Rog Beltmann said:
Great restoration work, Alain. Would like to see the insides as well ? Thanks for sharing the pics.
Click to expand...
Inside pictures of the Eico and the Sansui are at the end of the vidéo; I'm not at home, I'll make them if you want for the Dynaco and Leak next month
Thanks for comments!
Alain
 
slimecity said:
I had an Accuphase P300S and the manual for the P300 was substantially similar enough for me to do some serious work on it, including calibration.

Hopefully your protect circuit is working OK, as the analog IC in these usually fail.

Contact Rick at Stereomanuals.com - it will still cost - but a bit less than what Accuphase would charge.

I think Rick will only mail a hardcopy to you as well - thats how I got my manual from him.
Click to expand...

Thanks for your reply
I contacted Rick at Stereomanuals; unfortunately, he doesn't have the manual of the P300-S
When studying the circuit, I should be able to find the test points for the Bias settings, but do you remember the value of this Bias on your P300-S?
Regards
Alain
 
Hello again dear members,

Here I am again from France for the Accuphase P300-S and sorry for my English!
One channel is out of use (power transistors)
2SC1079 and 2SA679 can be found on the net, but probably fakes??
On a post from Audiokarma regarding the Pioneer SA-9900, the recommended substitutes for the power transistors (same as those of the Accuphase P300-S) are:
2sa679: ON-SEMI MJ21193G (PNP 250v 16A 250W 4mhz HFE 8-75)
2sc1079: ON-SEMI MJ21194G (NPN 250v 16A 250W 4mhz HFE 8-75)
Can someone confirm this choice for me?
Do they have to be paired?
(PS: For those who wish, I have the settings of the P300-S)

Regards
Alain

Last restoration... :
 
Hello Alain,

i just fixed a Pioneer SA-9900.
The power transistors 2SC1079 and 2SA679 on the left channel were all blown. I decided to replace all of them (on the right channel too) , because you won´t get the original types (didn´t dare to get TOSHIBA brand from china... they might be fakes for sure)..
The reason for that annoying bug was a tiny, but faulty poti for the bias, which caused a much to high bias. The thermal protection couldn´t save the semiconductors lives.

For the replacemet of the power transistors i finally used the substitutes you mentioned above, ON-SEMI MJ21193G (PNP) and ON-SEMI MJ21194G (NPN).
For the Pioneer SA-9900 i needed 4 pairs, but i ordered 6 pairs. So i could perform a coarse selection. The general problem is, that the NPN type seem to have a signifcant lower hfe than the PNP type. None of the NPNs reached the hfe of the PNPs. The difference was 10 ore even more. But this is not a serious problem. The gain of the output stage is not the same as the hfe of the transistors. The gain is given by the dimension of negative feedback. A final mesurement showed, that positive and negative halfwaves were complety congruent a no significant distortion was detectable.

Summary: You can use the ON-SEMI MJs without any concerns. (I ordered at Mouser Electronics)

Best regards
Juergen ($Pioneer$)
 
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