# Solid State Peavey Pacer 100 problems



## bcmatt

So, I have a friend that has a Pacer 100 from what we think might be the 70s. He was using it as a bass amp (whether or not it was made for that).

A few months ago it crapped out. It makes real farty noises as well as a bit of a bad sort of tremelo sound. It's scratchy/ staticky a bit too. Definitely not something you can use in it's current state. 

When I looked into it, I see that it was being used with a 4ohm cab even though the output says 8ohms. Could that be the cause?

Anyways, does anyone know what might be wrong with it? 
I really hesitate taking this in to an amp tech because I don't feel the thing is worth anything much anyways.

I have already installed a new 3 prong plug (the old one's ground was disconnected) as well as replaced a resister that had burn marks underneath it on the pcb. I think the resister had already been replaced and that was not actually the problem this time.
I will add some pics in a few mins.


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## bcmatt

Here's the pics:



















If the don't appear, they are at the top of the page here:
http://yeomansinstruments.blogspot.com/


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## Wild Bill

bcmatt said:


> When I looked into it, I see that it was being used with a 4ohm cab even though the output says 8ohms. Could that be the cause?
> 
> Anyways, does anyone know what might be wrong with it?
> I really hesitate taking this in to an amp tech because I don't feel the thing is worth anything much anyways.


You've probably blown the output transistors. Solid state amps are different than tube amps. They don't really have a specific speaker load. What happens is that as the speaker ohms gets lower the amp puts out more power. The design engineer will have spec'd a lower limit. If the amp says 10 watts at 8 ohms then if you plugged in a 16 ohm cab you'd get a lot less but if you plug in a 4 ohm load the amp will try to put out a lot more. Since the output transistors can't handle that extra power they overheat and burn out.

Anyhow, you can't really fix these things by just replacing stuff until it works. Well, you can but it usually takes a LONG time and a lot of extra money!:smile: You need to take measurements with a meter and understand what they tell you. Parts can look perfectly fine on the outside and be fried inside. Or, parts can look kinda burned but actually be ok.

It's up to you if it's worth bringing to a tech. I figure it would cost pushing towards $100 to fix, depending on the tech's bench rate.

:food-smiley-004:


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## SinCron

I have the same amp and I've never had that problem.


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## bcmatt

hmmm, ok, thanks Wild Bill. I'll let him know that. I'll pass on the information, and he can decide what he wants to do with it.

He has lots of time and no money and no job (he's not lazy, he recently had a heart transplant). Also, we live in a town at least a couple hours from any real amp techs. So, we'll see. By the looks of it, the cost of replacing all the transistors in the whole thing would be even cheaper than replacing all the scratchy pots, so maybe it would almost be worth it to try some blind transistor swapping. 

I'll see if I can look up how to test transistors with a DMM to see if they are operational. I suppose that could help in narrowing down the culprit.

In the mean time, he is using my YGL-3a for a bass amp head. I'm not sure exactly how safe that is for its output transformer, but at least the impedance is matched up with the speaker load. But, the fact that my Traynor is (maybe?) in potential danger, motivates my extra effort in this cause.

Ok, thanks for the tip, I'll look at the output transistors first. I never considered that transistors could malfunction. I always assumed that transistors came straight from Satan himself, so he holds them as impervious to destruction. I guess I forgot from my Theology studies that Satan is destroyed in the end. (man I am such a nerd)


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## Ripper

Check the board for cracks, bad solder joints etc. My experience with blown output transistors is that when they go, the go completely, no sound etc and in alot of cases if there isn't any protection diodes in the output circuit (alot of old SS amps don't have that) that it will keep blowing fuses. Had the amp sat for a long time without being used? It could be leaky caps in the power supply itself.


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## bcmatt

Well, I believe that it did sit for a number of years. He got it from his uncle several months ago. I believe it was probably not used for the last 10 years or so. It did seem to sound alright for a month or so before it went bad in my friend's possession. 
Will leaky caps affect the sound like that? I didn't think caps could go bad so suddenly.
Or could it be a chain reaction?
Hmm, it seems like the possibilities are increasing.

What are these amps even worth? If it came to having to take it to a tech and it costing $100, is it even worth that?


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## Ripper

Yeah the caps can go like that and can make sounds like that. The nice thing about it is that is one fairly simple looking amp by todays SS standards. Without being able to check it out it could be a number of things.
I'd jumper the caps with a couple of new ones and alligator clips just to try it before I went to the trouble of changing them, but like Wild Bill said, it might be the transistors. I have no idea what that amp would be worth, I guess it depends on the owner and what they want.


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## SinCron

I've seen these amps sell for up to $400 (it was actually in pounds but I forgot how much it was in pounds so I put the Canadian price I remembered) on the bay. They're not that bad. I like how the overdrive goes on top of the clean so you can still hear both.


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## bcmatt

SinCron said:


> I've seen these amps sell for up to $400 (it was actually in pounds but I forgot how much it was in pounds so I put the Canadian price I remembered) on the bay. They're not that bad. I like how the overdrive goes on top of the clean so you can still hear both.


Hmm, you're right. They are worth it to those that want them. It did have it's strengths. I just saw a combo version online for sale for 499 pounds. I doubt many would pay that. I guess if he likes it and wants it fixed, if the cost isn't outrageous, it is worth it. But really, he has no income, so if we can repair it for cheap, that would be best.


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## Hamm Guitars

Does the amp have a Power Amp in, a preamp out or an effects loop? Either would make it much easier to tell if the preamp or the power amp section is shot and it is allot easier to asses the damage when you know what part of the system is broken.

If it doesn't have any of these features, then take it to a tech a pay a bench fee to see what is wrong with it. If your bias resistor is burnt and you replace all of the output transistors, there is a real good chance you will loose the trannies again shortly after you turn it on again.


edit -

Just saw the pics - there are no in/outs that will help you. If you have a schematic you can find a good insertion point and test it, but if that is beyond your skillset a bench fee shouldn't be all that bad.


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