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Although the compliments are much appreciated, it is the hundreds of people here who check their egos at the door and contribute their accumulated wisdom that make this site a must read.

If any of the 700/400 xfmr's failed it would be an exception. They are the basic E/I steel lamination type and there is little reason to expect failures even at high power applications.

It's not likely the parts vendor info was ever made public as the repair people could use other sources and avoid the P/L markup .

What does the inverter waveform look like? Modified square wave? PWM?

I registered as a P/L repair facility around March of 1983. I requested manuals and received everything available at that time including a 37 page "SERVICE DEPARTMENT PARTS LISTING" dated 3/1/83. Ed, I'll scan the list and send it to you. Please message me with an email address. From 1978...

The 4000 preamp is a nightmare. It will have at least 100 cracked solder joints on the mother board. The RCA jacks are brittle and break easy. Don't bother plugging it in until you reflow the pins. Bring up the amplifier with the light bulb test set. Anything that has set, unused, for a...

See attachement.

1226

I doubt you'll notice any difference but it shouldn't hurt anything.

... Thanks for the kind comments. It's rare that I get any feedback and good or bad, much appreciated.

The date code is 40th week of 2001. (0140) they appear to be legit RCA's. Ideally all drivers would be RCA410's. If you're buying transistors, pick up Berquist silpad insulators. No grease required.

Ed, It's good to see you still sharing your infinite P/L wisdom.

are the meters analog?

The schematic for this amp is nearly impossible to read and understand. There is a time delay relay on the transformer primary acting as a soft start. Q508 controls the relay. I would check it.

As for the grease, less is more. All that is needed is a pencil eraser size dot between the two pins on both sides of the mica.

Last year I drew up the conversion in power point and saved to pdf. I used a lot of Ctrl-c, Ctrl-v. See attached. As for silpads I've only installed a thousand or so with only a handfull that I over tightened. Use thumb and index finger to lightly grip the nut driver. Turn until it slips...

Is this amplifier quasi complimentary or full complimentary? Quasi complimentary will have all NPN outputs such as MJ15024, TP9054, or 2SD555. Full complimentary has PNP and NPN outputs. The manual was written for quasi-comp. That could explain differences that conflict with the manual...

I don't understand what the high resistance is. The most common failure mode of transistors is zero ohms across one or both the junctions. In other words, if it's not shorted, it's good. Take that approach first. On the board, R101, 7.5k/2w has shown failures in the past.

There are shorted output transistors. The 700II manual is attached. Read the troubleshooting section for checking transistors and do exactly what it says. Note that the manual was written before digital meters were available.

I second what he said, with the exception that "anf" should be "and". Sorry Lee, you were 99% correct. The RCA 410's (located at the bottom of each heat sink) are a must for stability. Mj15024's can be used for outputs. See service bulletins in attached manual