Peavey 8.5C what's this transistor?

[Pbassred]

I wanted to find out what the power devices were on my stage amp, so I pulled the lid off. They are labled "70473180 W9650 Motorola". I've searched on this and can't find anything.

[destroyer X]

Maybe you know, but you can put others.... measure voltage, and knowing power output, you can conclude the one to put there.

Transistors have Gain, Maximum Voltage, Maximum Current, Better operation voltage (charge line) and maximum frequency they can operate.

More then 30 of gain can use...if better than 100 very good.

Voltage capacity of transistor without explode is important, use units that can hold double voltage related your supply... as a minimum...better to be more than that.

Also current maximum is too much important... evaluate by fuses or power maximum current, put, at leat twice capacity current to 4 ohms charges....better to put transistor that can hold a short.. that's the way i done...if can be alive with a short will be good to me... also power supply have to support a short of minimum 3 minutes (the time maximum you delay to perceive sound finishes... and get out from waterclosed to pull outlet pins).

That's reason my name is destroyer.... not difficult to understand.

This way i use to put 6 pairs, 8 pairs, 12 pairs 15 pairs... the whole i need to maintain alive....output transformer i evaluate shorting it using 200 amperes amperometer. Bad things never survive here.

Also take a look at maximum frequency.... 3db point.... this way avoid the ones that goes only to 100 kilohertz...better 300 hundred kilohertz.

People say that transistor sound diferent... and you have to put same one (never found two exactly same)..... in old factories they made and them discovered what transistor they did!

I, unfortunattely, could not perceive those differences...but i believe in vodoo and some crazy things... this one is easier to believe without problem to me.

If you already knows, sorry, trying to help

Some people afraid of vodoo.... that's mankind.

Carlos

[Netlist]

Here are my assumption based on what I recall from a Peavey service technician.
704: Peavey ID
7: PNP
8: NPN
1/3/4: Probably VCE
140/180: don’t know. /maybe max current.

So far I encountered the following device in Peavey gear:
704-7-1-140
704-8-1-140
704-7-4-140
704-8-4-140
704-7-3-180
704-8-3-180
704-7-1-180
704-8-1-180
.......

You can safely substitute them with MJ1502x series.
Credits go to Moamps too.

/Hugo

[moofer]

i got the full parts list from peavey for this amp if ya want it

[Centauri]

70473180 is Peavey in-house numbering for MJ15025.

Cheers

[Diode]

With respect,

I hope you can fix it yourself. If not, those amps were made to throw away. The PV series amps are intermittant duty amps ONLY. eg. PV2K. I used to service said amps and I know that the driver boards need THOROGH checking. I usually suggest changing all semiconductors but if you are experienced in this, you can do the driver boards with only a handful of parts. Be careful and check the crap out of everything or it will blow up again, with no chance to stop it. Personally, I'd keep the PS parts and chuck it but to each his own....

Sorry to be so negative but I KNOW these amps......

Good luck,

Chris

[Pbassred]

I never said it was broken. I just asked what they were in case it does.

[Diode]

Sorry man,
I misunderstood. Usually, when people ask about that kind of thing, they want to fix something..... Again, MY mistake....

Chris

[Original Burnedfingers]

To answer the question...

The original in-house number was SJ-8333 the alternate in house number was 73180 and the field replacement number is MJ-15025
the order number is 70473180 and its a PNP 180V output. This information is according to Peavey's semi-conductor/transistor cross-reference list.

There is nothing mystical in the Peavey amps that makes them any more prone to blowing up than any other brand. Common sense repair is the difference between a repair that lasts 10days and one that lasts another 10yrs. I have repaired this amp and have found it to be as simple as other amps to repair.

Joe

[Pbassred]

Usually, when people ask about that kind of thing, they want to fix something.....

Understandable. We live in a short sighted world where no-one botherers to find out how things work until they don't.