Duece VT 240T head 412 cabinet ++

Eallenguitars · Post by **Eallenguitars** » Thu Mar 11, 2021 10:46 am

Glad to be new to the group! Thanks for the add!

I used peavey equipment back in the 80s when I was gigging but haven't been around it for many years. Always work horse equipment!

I came across this treasure trove of old Peavy equipment in my guitar work from an old guitar player who passed away. I would love any insights on these great old peaces! I havent had the time to fire anything up to see if all works but everything appears to be original!

From reading the serial # info on the forum I learned the following.
-Duece VT head appears to be 1977.
-412 enclosure is 1975.
-XM4 Mixer amp is 1978
-122 International Speaker are 1977

Any like and dislike from your experience with any of these?

I dont know that I will get rid of any of it but If everything works, does any of it have value beyond the cool factor?

Eric

Eallenguitars · Post by **Eallenguitars** » Thu Mar 11, 2021 6:10 pm

I got a chance to plug in the Duece head. Unfortunately no power revealed the fuse blown. A fuse replacement resulted in an immediate fuse blow when the switched was flipped. I will have to pull the tubes when I get caught up on my backlog and see what happens.

Any typical issues with these besides tubes behind blowing the fuse?

Also, the standby and power switch on the front are obvious. What are the left and right directions on the 3 position toggle on the back?

Eric

Eallenguitars · Post by **Eallenguitars** » Fri Mar 19, 2021 4:02 pm

One culprit found! Could there be more?

I grabbed a few minutes between nitro coats on a guitar build today to pull the amp from the cabinet to take a quick look.

The power panel has this nice burned color cap and board. Not sure what else is fried yet. The resistor in front of it checks fine but have yet to check the other caps and resistors on the power panel. The indents on the end of the large caps are no longer indented so I plan to go ahead and replace all 4.

The tubes do all check good for filament continuity.

Any other suggestions to check before putting on new caps and giving it a try?

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Lester H · Post by **Lester H** » Sat Mar 20, 2021 3:00 pm

I'd say you're on the right track replacing all 4. However I don't know enough to tell you if something else caused the capacitor to fail or if it was just age. The amp could have been subject to a lightning strike at some point during all these years. I have an old PV Rock Master head and I recently blew that greenish colored resistor in front of your blown cap. A shorted out tube caused it to fail. I put in a new one and all is going well again.

As far as value goes? Unfortunately not a lot. Its probably worth more to a Skynyrd fan having no luck finding a Mace. I used to have a 412 cab like yours but that thing was way too big and way too heavy to be toting around and we're currently living in a world where small, low wattage amps are king. But it seems like since PV moved all their amp manufacturing overseas the used prices of the old American made amps have increased in value some over the last couple of years.

Those old 4 channel powered mixers were very reliable and great for their time but there are so many affordable powered mixers with twice the channels plus effects and super lightweight class D power supplies available today that it would be almost impossible to get much money out of it.

I'm kind of a gear hoarder so I say if you have the room for it keep it.

I think you're old friend wanted you to start up a band again

Pappy B · Post by **Pappy B** » Sat Mar 20, 2021 4:46 pm

It looks like to me that the 470 ohm resistor is a replacement and the original burned up leaving some residue on the nearest components. But if it was mine and I planed to keep it I would replace all the electrolytic capacitors. Start with the ones in the power amp and get it working correctly.

Eallenguitars · Post by **Eallenguitars** » Sat Mar 20, 2021 8:03 pm

Pappy B wrote: ↑
Sat Mar 20, 2021 4:46 pm
It looks like to me that the 470 ohm resistor is a replacement and the original burned up leaving some residue on the nearest components. But if it was mine and I planed to keep it I would replace all the electrolytic capacitors. Start with the ones in the power amp and get it working correctly.

Thanks for the input!

So are you saying you think it was the 470k resistor that left all the burn residue rather than the cap, or both from blowing different times?

Lester H wrote: ↑
Sat Mar 20, 2021 3:00 pm
I think you're old friend wanted you to start up a band again

Actually, any I keep will never leave my shop and only stay to give another old days option for people to try out guitar builds when they come to pick them up.

I don't play any instruments any more and just stick with building, and what sound stuff I mess with is all digital

Thanks for the insights as well.

Pappy B · Post by **Pappy B** » Sat Mar 20, 2021 8:42 pm

The burn marks could be solely from the resister burning up. But it is also quite possible one took out the other. It wouldn't hurt anything to change out those 4 caps. Given their age one or more could be leaking if not not completely shot.

Lester H · Post by **Lester H** » Sun Mar 21, 2021 8:29 pm

Pappy B wrote: ↑
Sat Mar 20, 2021 8:42 pm
The burn marks could be solely from the resister burning up.

I didn't see his last photo but you're exactly right. When I burnt out that resistor in my Rock Master the burn marks looks exactly the same. It blew my resistor in half and let out a fair amount of smoke lol.

I totally agree the caps need changed but now I'm starting to wonder if the immediate fuse blowing could be the product of a bad power transformer.

Eallenguitars · Post by **Eallenguitars** » Tue Mar 23, 2021 2:34 pm

Pappy B wrote: ↑
Sat Mar 20, 2021 8:42 pm
The burn marks could be solely from the resister burning up. But it is also quite possible one took out the other. It wouldn't hurt anything to change out those 4 caps. Given their age one or more could be leaking if not not completely shot.

In retrospect of your comment and the fact that the current resistor has no burn marks on it I think the burn marks are from a previous resistor that has been replaced. The resistor not being burned is what led to me thinking it was the cap. That means the cap may not be the source of any Mark's, or the problem. Unfortunately if that is the case it leaves the question of what is the problem? I hate just throwing money at guesses almost more than digging cobwebs out of my brain to trouble shoot electrical.

Lester H · Post by **Lester H** » Tue Mar 23, 2021 4:43 pm

Eallenguitars wrote: ↑
Tue Mar 23, 2021 2:34 pm

Pappy B wrote: ↑
Sat Mar 20, 2021 8:42 pm
The burn marks could be solely from the resister burning up. But it is also quite possible one took out the other. It wouldn't hurt anything to change out those 4 caps. Given their age one or more could be leaking if not not completely shot.
In retrospect of your comment and the fact that the current resistor has no burn marks on it I think the burn marks are from a previous resistor that has been replaced. The resistor not being burned is what led to me thinking it was the cap. That means the cap may not be the source of any Mark's, or the problem. Unfortunately if that is the case it leaves the question of what is the problem? I hate just throwing money at guesses almost more than digging cobwebs out of my brain to trouble shoot electrical.

Supposedly if you pull the power tubes and install a new fuse and turn the amp on and if the fuse doesn't blow without the tubes you have a power tube issue. If the fuse still blows then you have another issue. In that case I'd probably test the power transformer next.

Eallenguitars · Post by **Eallenguitars** » Sun Mar 28, 2021 5:56 pm

Thanks to other threads on this amp on the forum a little troubleshooting and component checking let to finding one of the two diodes on the power tube board bad as well as a cap on the main board.

While the rest of the caps and diodes test good I went ahead and ordered replacements for the remaining large capacitors.

The initial capacitor with the burn on the powere board actually tested good, thought I went ahead and replaced them along with the resistors around being on order. I am confident the burn was from the resistor that was replaced by the large green 470k resistor.

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Eallenguitars · Post by **Eallenguitars** » Tue Apr 06, 2021 6:57 am

It is ALIVE!

All large caps and the tube panel diodes replaced and reassembled. I removed the tubes and fired it up 1st on standby, then off standby, then added tubes & a faint orange glow emerged.

A quick plug into a speaker and a strum of a guitar and sound came forth! Thanks to all for the input!

Now for the non-existing reverb tank removed at some point in history. Any advise on a good quality one to get for it?

Eric

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Peavey Forum

Duece VT 240T head 412 cabinet ++

Duece VT 240T head 412 cabinet ++

Re: Duece VT 240T head 412 cabinet ++

Re: Duece VT 240T head 412 cabinet ++

Re: Duece VT 240T head 412 cabinet ++

Re: Duece VT 240T head 412 cabinet ++

Re: Duece VT 240T head 412 cabinet ++

Re: Duece VT 240T head 412 cabinet ++

Re: Duece VT 240T head 412 cabinet ++

Re: Duece VT 240T head 412 cabinet ++

Re: Duece VT 240T head 412 cabinet ++

Re: Duece VT 240T head 412 cabinet ++

Re: Duece VT 240T head 412 cabinet ++