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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

Attached is the manual.

The contact only provides base drive to the pass transistor in the power supply. The design allows the use of a low power switch. The condition stated above suggests Q1 has shorted.

I'll bet they don't publish any time/current curves.

If you read the troubleshooting section off the service manual, and do exactly what it says, you'll likely find the trouble. Note that the manual was written before we had digital meters. You can invest in an analog meter like a Simpson 260 and follow the manual verbatim.

Try slowly opening a knife switch with 100 VDC and watch the fire ball. With care you can sustain a very nice arc, right up until it melts down into a puddle. My bleeder resistor is hard wired to test probes. When you make the connection to the charged cap, jam it on there and leave it for a...

For discharging caps there are plenty of options available. If some kind of a mechanical switch is to be used, the contacts must be rated for the DC voltage applied. Any ice cube relay is rated for 250 VAC and 32 VDC. The reason for only 32 VDC? When the contacts open, arcing occurs as any...

Here's an EBAY link for the switches I used. EBAY link To clarify the listing appears to be the same as what I used. Have to be careful using a switch on the bleeder resistor. Contacts rated for 100 volts DC are rare. I don't have a switch on my bleeder.

A few things to consider: Ideally, the fins would be facing inside so the fans push air across them. A switched 1:1/10:1 voltage divider that feeds the scope. The first time I did that I used 1k and 10K. WRONG! 10K and 90K or some multiple of that. You mentioned you will have two monitor...

Unlike electrolytic caps, which becomes open as the electrolyte dries out, the failure mode of tantalum is a short. The attached document discusses tantalums on page 5.

Yep, same here. That is one of few exceptions to my rule that semis are run to fail. I see people buying these repair kits on EBAY and change out every transistor and diode. Changing out diodes and transistors that haven't failed does not improve reliability. The potential damage to the...

Did this thing take on water? Otherwise, it's not common to see rust on transformers. The Luxman I'm working in has the same glue/resin all over the place. I don't think it's glue because the same gunk is under 1/4 watt resistors. There is none under the electrolytic cap, just around the...