There is a website for these.

http://thecarversite.com/

THAT is where you get information on these. I bought one with a fried right channel a couple years ago and due to improper servicing it had blown it all the way back to the current limiters. Surprisingly it did not blow the drivers, but it did blow one predriver. I forgot what I used for those but I DID look at spec sheets etc. because you don't just go to NTE and get transistors for something like this. If you need anything other than the outputs I will find you the correct transistors, don't trust anyone on this. A couple of them are germanium.

The current correct output transistor type is MJ15024 available from Digikey for reasonable, about five bucks each. Replace them ALL in one bank, no exceptions. Each in a bank of three has to equally share the current, and rated down to four ohms with 85 volts rails that pretty much stay put, you don't need any current hogs. That's what happened to mine, it blew the emitter resistor on the one in a bank used for current detection. This is why it blew the predrivrs but not the drivers.

Remove the transistors for checking, all the resistances are too low in the whole thig to do it in circuit. Check ALL emitter resistors. After all is said and done, you can run it on the bench without a load connected with all of the outputs removed and it should look right on a scope, with possible SLIGHT early clipping on one side of the waveform.

There are two types of these, most use all NPN outputs and drivers, the other uses complemmentary. As far as I know only some of the Series Two amps were complementary. If it has the LED meters you don't know, those were built around 1979 and 1980 right after Pioneer bought the company. These have an IC on the board rather than the usual diff pair at the input.

The older ones with the analog meters as fas as I know all used all NPN outputs and drivers.

After I got the right channel fixed I was jamming it and the damn left channel fried. The reason was that where the heavy wires act as a bus and connects all the collectors together in one of the banks of outputs had come loose, it broke the solder over the years. Check ALL connections to ALL outputs because even one of them off can fry the whole channel.

Really, if you are not used to working on high power amps like this, you could waste alot of silicon.

The price break on the MJ15024s comes at ten pieces, so just get twelve and replace them all. With any luck they will all be from the same batch so matching will not be a big problem. There is a matching procedure required after replacing the outputs to assure they are properly matched. If not they could fail prematurely when pushed hard, and you buy this amp to push it hard.

A short at the output terminals should not fry this amp, but connecting it to certain low impedance loads can. The book says never go below four ohms, but many four ohm systems do just that. Bob Carver knew this and set the current limiting to handle probably down to about three ohms because of those gnarly woofers and infinite baffle systems of the day, but any lower and it is vulnerable.

Aso note these amps have abslutely no speaker protection whatsoever, no relay no nothing. They recommend you use speaker fuses calculated to your particular speaker handling capabilities, the formula is in the book.

If you buy the manual you have been scammed, it is available for free not only from carversite, but a few other places. I think you can get it at bama as well, but the best one with the addendums etc. is at carversite. There is a note about certain Infinity speakers that use some ungodly high value cap in their crossover that affects the power down of these amps and can result in a transient if turned back on too quickly. If you got this, you got the right manual. Also note that you do have to sift through that manual as more than one version is covered.

When you get it working you probably won't want to sell it. Even at flat response it sounds better due to an extraordinarily high damping factor. This is one of the few amps that can really benefit from heavy guage (and short) speaker wires. The cones of the speakers act like servomotors actually. Mine is not for sale except under extreme duress, and I mean for alot more than it's worth. You can't buy an amp like this for less than twice what you could sell it for.

So fix it right.

There is a guy on eBay who claims to fix these right for about $350 no matter what is wrong with them. Of course two way shipping is probably extra. The point is, there is a reason people don't fix these things for a hundred bucks.

Get the ohmmeter out before even plugging the thing in and keep us posted.