Schematic wanted

Peavey MX VTX 1x12 combo amp.

This is my amp and had been sitting for a year or so. When I switched the standby rocker to low I heard a mild pop from the speaker and after that just a faint amount of signal from the guitar out the speaker. Plus the status led doesn't light. I've never had problems and the tubes are a matched quad Philips 7591a JAN/NOS with low hours.

I'm sure the B+ is missing, the tubes don't heat other than the filaments. And I probably don't really and absolutely need the schematic but would like to have one on hand regardless.

FWIW....Peavey sent me a schematic for my original Deuce amp but that was 15 years ago now. Might want to check with them though, to see if they still supply schematics, if you have no luck here. :-)

Update....did a quick google and ran across the following:

Following the link one of the participants posted resulted in the following:

whoops...sorry sent wrong url in last message. Should have been this one:

Odd I didn't see this site when i googled it

Thanks much.

Looks like an internal fuse for the B+ per the schematic. The HI/STANDBY/LO switch rocks back and forth between taps on the secondary to get either 262vdc or 525vdc for B+. I've seen fuses in this situation blow because of age and no other apparent reason specifically another amp I own a Peavey Artist 115.

Whatever tubes are in it is irrelevent. Why have you said this?

Have you measured the B+ yet? Might be a very easy fix that doesnt really and absolutely need the schematics.

Sorry you feel that way but you couldn't possibly be more incorrect.

I built my first class AB tube guitar amp back in 1972 from scrap. Please don't insult my intelligence with your idiotic banter.

Maybe you could use your intelligence to measure B+ then.

Maybe you could measure your intelligence in single digits.

Now you're sounding like a 12 year old.

base32 ?

Sorry, had to put it in a context you'd understand.

You're still sounding like a 12 year old, I'm afraid.

You're afraid of what?

Here's an idea or two (for a typical 6L6 / EL34 push pull circuit):

First you really should assume that one or more output tubes may be faulty. So turning on the amp and seeing if any of them get hot while they melt the OPT is probably best avoided. Remove all the output valves and you can then easily measure the HT on the Anodes and G2's as well as the bias voltage (perhaps using a Variac to slowly ramp up the voltages). With the amp off and the HT discharged you can then measure the integrity of the output stage by measuring the presence of all the G2 and Grid resistors, again from the output sockets. You can also check both anode pairs are connected, the cathodes all grounded (perhaps via low ohm resistors) and that the OPT primary is present between the appropriate Anodes, again all from the output sockets. You can measure separately each half of the OPT primary via its HT connection and the oputput sockets to check for possible shorted windings. Check the presence or not of the secondaries at the speaker jack socket. You might also check that no secondary winding has any connection to the primary.

Once the output stage has been thus checked, and thus your OPT protected, you could sub in a known good set of output valves and, (perhaps running up slowly with a Variac) see if the amp now works, confirming whether your original set of valves are faulty. If your amp has a Fender style Power Amp In jack, this is a good place to inject the signal to properly test the output stage.

Notice that at no point was the make and model of output tubes mentioned. If you have subbed the 6L6's for 7591's you just need to measure at the (different) appropriate pins, and replace with the same type if necessary.

Now you could check the preamp section by injecting a signal. If no signals appear at the output socket grids (output valves removed again), the preamp is broken. Or you could use the now tested output stage to monitor the preamp. Swap all the preamp valves with known good ones. Check there is HT on every preamp valve Anode. Follow the injected signal from tube to tube and see where it disappears. Tap with a wooden or plastic object to see if you have any dry joints etc etc etc.

But I'm sure you know all this stuff already.

Yeh and I really don't know why you would waste your time with such a juvenile entity as myself.

I replaced the 1amp fuse between the bridge and the B+ secondary and all is well. Didn't bother taking voltages or other tests.

Oh and I forgot to mention I worked for a company that did Roland, Yamaha and Peavey warranty to name a few. I have a file cabinet full of service literature for Peavey gear just not the MX-VTX.

Have a great life.

Yes, you love telling us all about yourself and your gear, don't you.

I seem to recall a recent post by Mr N. Cook about rewinding pickups for a AB Landola guitar he had for repair. You posted 2 links to pictures of YOUR guitars and then went on to tell us all what projects YOU are doing now. In this thread you first boasted unecessarily about YOUR fancy JAN tube replacements, then told us YOU'VE been building amps from scrap for centuries, and now that YOU did loads of warranty work and have filing cabinets full of schematics.

If you are such a techical Wizard, why then did you need to post here asking for schematics and boasting about yourself, when the only problem was a blown fuse?

I could probably find lots more examples of your sad posts, but I really can't be arsed.

Good day, Sir.

Hmmm, sounds of pennies dropping - you didn't perchance happen to buy a matched quad of 7591 valves and plug them into your amp meant for 6L6 without first rewiring the sockets?

Do you have some mental issues?

Scroll down to the 7581a/KT66 paragraph.

Yes I know before you whine about it I incorrectly labeled them as

7591a only because the amp had been stored for a couple years and I had forgotten the exact number.

However both are pinned the same and have like characteristics.

All this aside, the amp was stored in working condition. Taken out of storage and promptly blew the HV fuse. Fuse was replaced, amp was load tested for an hour at 50% output and passed with flying colors.

Now, be a good boy and piss off.