Accuphase P-11 power amp schematic added.
In my notes I see: " Q6, Q7 : 2SC2459, 2SA1049, discrete and thermally coupled".
This means
- I replaced the original double transistors with the discrete pairs or
- they have been in there as made by Accuphase. I do not remember.
This time the guy at the copy shop said he will reduce his scan prices
so take your chance to ask for more schematics (see post 1).
In my notes I see: " Q6, Q7 : 2SC2459, 2SA1049, discrete and thermally coupled".
This means
- I replaced the original double transistors with the discrete pairs or
- they have been in there as made by Accuphase. I do not remember.
This time the guy at the copy shop said he will reduce his scan prices
so take your chance to ask for more schematics (see post 1).
C-240 preamp schematic and alignment instructions are here.
In my notes I see: "D13, R17 and D9, R39 positions interchanged"
and
"error in the schematic", Q31 is shown with reversed polarity Collector / Emitter.
In my notes I see: "D13, R17 and D9, R39 positions interchanged"
and
"error in the schematic", Q31 is shown with reversed polarity Collector / Emitter.
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Service manual for M-60 mono power amp can be asked for by pm
because "your file of 1.38 MB bytes exceeds the forum's limit of 976.6 KB
for this filetype", thanks for the contribution of somebody (this is the first
time a third party added useful Accuphase schematic info here).
because "your file of 1.38 MB bytes exceeds the forum's limit of 976.6 KB
for this filetype", thanks for the contribution of somebody (this is the first
time a third party added useful Accuphase schematic info here).
Last edited:
E-550 Service Manual
Service manual for E-550 Integrated Amp available. To big to upload. Ask.
Regards
Service manual for E-550 Integrated Amp available. To big to upload. Ask.
Regards
Accuphase C240
Hi.
Found an old post where you wrote that you could help with service manual for Accuphase C240. If this is still possible I like a copy. I am restoring a C-240 with right channel dead. Hard to find service-manuals for this product.
Greetings
Morten in Norway.
Hi.
Found an old post where you wrote that you could help with service manual for Accuphase C240. If this is still possible I like a copy. I am restoring a C-240 with right channel dead. Hard to find service-manuals for this product.
Greetings
Morten in Norway.
Accuphase Preamp Repair
Once again a preamp fault was caused by a short in some (foil ?) capacitor.
This is a rare failure mode, but frequently enough to be mentioned here.
I talk about the small radial lead caps which look like a brown pillow - like
the four near the t-corners in the attached picture.
So if everything else fails in your error search have a look at one of these.
Most of the time single channel only, signal may be there, but "wrong".
Once again a preamp fault was caused by a short in some (foil ?) capacitor.
This is a rare failure mode, but frequently enough to be mentioned here.
I talk about the small radial lead caps which look like a brown pillow - like
the four near the t-corners in the attached picture.
So if everything else fails in your error search have a look at one of these.
Most of the time single channel only, signal may be there, but "wrong".
Attachments
This particular one was in a C-230 (Phono RIAA).
Do you have a sample picture of the green caps ?
Do you have a sample picture of the green caps ?
brown or green are the same. Polyester capacitor in the feedback network. If You test it out of circuit are with dancers values.
Accuphase E-550 full service manual (8.1MB)
via email, your pm must include e-address.
Schematic of single channel power amp only is here :
https://www.diyaudio.com/forums/sol...-bjt-mosfet-broken-accuphase.html#post6481560
and said can be used for Accuphase E-460 also.
via email, your pm must include e-address.
Schematic of single channel power amp only is here :
https://www.diyaudio.com/forums/sol...-bjt-mosfet-broken-accuphase.html#post6481560
and said can be used for Accuphase E-460 also.
Hello Folks,
Anyone can share the Service Manual for the E-530?
Is it very different from the E-550?
Thanks!
Anyone can share the Service Manual for the E-530?
Is it very different from the E-550?
Thanks!
Preamp C-280 low level amplifier problem
Hello,
After repair of a C-280 preamp, one low level amplifier make some noises very loud.
Step a: In a first time, I thing it's a problem with a TO92 small signal transistor, but the replacement of them doesn't change anything.
Step b: After the replacement of the mica and styroflex capacitors, the problem is fixed 🙂, but after that, there was a hum
after one minute power ON.
In Step a, I replaced Q1-Q2-Q7-Q8 (2SC2602-G / 2SA1114-G) with paired BC550C/BC560C transistors. I put again the originally Q1-Q2-Q7-Q8 transistors and the hum problem was fixed, the preamp works fine today.
So, take care when you replace the small signal transistor on a MC amplifier ........
Hello,
After repair of a C-280 preamp, one low level amplifier make some noises very loud.
Step a: In a first time, I thing it's a problem with a TO92 small signal transistor, but the replacement of them doesn't change anything.
Step b: After the replacement of the mica and styroflex capacitors, the problem is fixed 🙂, but after that, there was a hum
after one minute power ON.In Step a, I replaced Q1-Q2-Q7-Q8 (2SC2602-G / 2SA1114-G) with paired BC550C/BC560C transistors. I put again the originally Q1-Q2-Q7-Q8 transistors and the hum problem was fixed, the preamp works fine today.
So, take care when you replace the small signal transistor on a MC amplifier ........
I very much doubt that replacing the transistors alone brought somehow hum. Any chance the different pinout caused issues?