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Reading 2325 schematic,newb at this. Learning process.

I talked with Mouser at length for at least an hour. I will call tomorrow and verify that number. Thanks
 
Ok. Talking with mouser again, the problem is there are suffixes on the KSC2383 which pertain to the gain of the transistor.
I have 2 choices. the suffix O has a gain of 100-200. And there is the suffix Y which has a gain of 160-320. And that was the same problem with the 2SC 2383Y(on hold pending clarification) which they have with the higher gain of 160-320. So which gain am i looking for?
Thank you eastpoint for the offer, i may take you up on that. In the mean time will just need clarification on the gain that i need for this application.
 
The service manual calls for the 2SC1318, gain code Q or R. Q has an hFE range of 85-170, and R has a range from 120-240. So, KSC2383OTA with a range of 100-200 is probably technically the best sub. But I expect either would work there.
 
Thanks Steven. Im on hold now with mouser.lol

The deed is done and the experience was painful. Im just gonna book myself at the dentist for a relaxing root canal.
 
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Always get the KSC2383YTA. I know the others will work, but literally every parts list anywhere uses the Y, not the O.
 
lol. Likely story. Actually,the worst thing is sitting with your mouth open for long periods and trying to swallow.
Maybe instead i will book another IMS treatment. That is definitely not fun. No tears of joy i tell ya.:)
 
Update.
I replaced all transistors and electrolytic caps on the buffer amp board(PH01).
That changed the input and the 1k wave is clipped a bit. And the output now is symetrical but wave form is distorted. Hmmm.

Input
oTvchPZ.jpg


Output of PH01 board.
AtvJxkn.jpg
 
What is the DC voltage at the junction of HH05 and HH09 (HH06 and HH10 etc). It should be about 16 volts.
 
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Hi Guys. Ok. I had all the 2sc1815 in backwards as these original 1345 are a square trx and i figured the writing would signify front but no. So anyways after testing ,those are in properly now.
Wave forms now are good at input. Output is wonky but symetrical. So something still amiss.

Input
Oo2B9gc.jpg


Output
rkbz5d9.jpg
 
Look at the voltages on the transistors. The output from that circuit should be a similar amplitude as the input. From the second waveform, it looks like there is a supply voltage issue or something. That waveform is showing tremendous crossover distortion (and too low an amplitude)

Check the voltage on the emitter of HH05 (or HH06), it should be about 32 volts, and the voltage on the collector of HH05 (or HH06) should be around 16 volts. If the voltages are low or missing all together, look at RH28 (100 ohm). If the resistor is getting hot or is burned up, look for an issue in the other two amplifier circuits (tape signal path) that could be causing an overload (transistors in wrong or something), as they run on the same supply from RH28.

Also be sure that you have the correct polarity transistors in the correct place (PNP for HH05-HH08, NPN for HH09 & HH10 etc)
 
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Hi Bob. HH01 base has -3.7v dc to ground. E and C, 0 V. hh05 has 0 volts in B E C. The rh28 looks fine, not hot or warm. 0Volts on either end.
 
Well there is your problem!!! You don't have any B+ on the board. What you are seeing on the output is just the signal making it through without B+. The 35 volts for thhe PH01 board is supplied directly from the 35 volt regulator (J805 on the P800 regulator board). If you have the 35 volts on J805 of the P800 board, then look for a broken wire in the path to the PH01 board. I think you "have the cat by the tail" now.
 
Hi Bob. Fuse burnt on p800 board. I have what looks like the exact amplitude on input and output. Perfect 1k sine wave.
Listening to it now. I have both left and right channels ,but still get the odd pop like static on cold start. Gonna give it a listen and see how far it goes. So far its 100% better as i have full control of the dolby NR pot. Clean sound so far. Thanks very much for the help so far. Gotta figure out what the odd pop is but will listen for a while.
Cheers Colin
 
I have a 2325 that had a noticeable "sizzle" sound for 10-15 seconds after every cold start. I looked in vain for a long time, and finally decided to live with it since it went away so fast. Then a few months back, AK member @richardg0n posted a fix from a similar problem. He replaced a few transistors on the PE01 board. I did the same, and son of a gun, it worked. Completely eliminated my noise on startup. Read his post and see what you think.
https://audiokarma.org/forums/index...pre-has-no-output.901232/page-4#post-13567760

And my post where I reported that his fix worked for me.
https://audiokarma.org/forums/index...-with-power-up-“sizzle”.905630/#post-13570243
 
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