Heres a fun one, a Marantz Model 22, back when Marantz started going over seas to Japan, we see some of the techniques used here on the 22XXs a lil later on.
P800 Power Supply
The 1000uf capacitors have a common ground/case not typically in later variants, the trick is getting the right lead spacing here. The particular power supply is rather interesting, consisting of a dual power supply, on half is dedicated to the AM/FM stages and the rest for amplifier phone/pre sections. P600 and P700 PCB's.
Lytics here were replaced with Panasonic FR and FC's.
P400 Tone
Silmics and Nichicons were used extensively on this board, transistors at H401/402 were replaced with matched hfe KSC1845's.
P300 Phono
This is a pretty familiar design I've, the lyrics here were replaced with Silmics and Nichicons
P600/700 DC FM/AM Amplifier
The latter half at P600 is used for the amplifier board on this model through the dual PS. Just a few lyrics here to replace with Nichicons, I also replaced the large films with Panasonic ECW PP type. The Bias can be obtained across either emitter resistors R651-654, adjustments are bad off the board back behind the transistor TO-3 bank, the pots center stage are Offset adjustments. New Mica insulators and thermal compound was applied. P700 was recapped with Nichicons and Silmics along with H705/706 (2SC732) replaced with matched KSC1845's.
I also recapped the speaker relay PCB at P980 with Nichicons while we have access and are addressing the PS and such.
Heres a listed of noted service bulletins -C807
P500
-180K 1/2 RESISTOR (H509 C TO GROUND)
P600
-R617/618 9.1K 1/2 RESISTOR (WAS 10K)
P800
470uf to 330uf @ c804
H801/802 Transistor Upgrade (done prior on most units)
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