AMP Problems, Help please!!!!!!!

[songwriter7]

Ok, I just bought a Traynor YCV40, and I love it. Sound is phenominal. I ordered some jj tubes for it, and upgraded to KT77 tubes instead of the 5881 Sovtec, I was told it would do no harm to my amp, and it didn't, I did the harm. Ok here's what happened, I had them in it was working fine then I tried some tube dampners, so I took the tubes out to put the dampners on, then I put them back in.I turned it on to check them out and it didnt work, I quickly found I was careless and put one in wrong and broke the plastic middle of it. The part that is surrounded by the pins. So I got it out and the piece, put the old tubes back in it. Turned it on, but no sound. The tubes are heating up and glowing correctly, I dont know why but it wont make any sound. Does, anyone know what might be going on? I am relatively new to the tube scene. Please help.


Merry Christmas Everyone!!!!!!!

[Rigormortis]

Hope you get it diagnosed! Just a bump for you.

I have a Traynor YCV20.

[petemoore]

Other than a problem tube..always the first thing to check...
Does, anyone know what might be going on?
We're on page one..it doesn't work and needs to be debugged.
I am relatively new to the tube scene. Please help.
First line of advice is take it to a tube tech.
It is probably something simple.
Second line of approach might start like..
1 Shelve the amp.
2 Read up on tube amp safety.
3 Read up on tube amp Debugging.
4 then decide on a prudent course of action.

[Regis]

you probably fried one or both of the kt77's. Put the 5881's back in and see what happens. If they work, then buy new kt77's. If they don't, take the amp to a qualified amp repairman.

[ricach]

Regis - I think he said he did put the old tubes back in.

I'm curious how it was possible to put the tube in incorrectly? Isn't it 'keyed' to prevent such things? Does it make any sound at all? No hum, crackle, pop? If dead silent, look for the obvious first - maybe speaker got unplugged?

If you're up for the adventure, take petemoore's advice and then troubleshoot it yourself. There are plenty of people here that will be glad to help. Even if you don't feel comfortable doing the repair yourself - you'll feel good letting the tech know what you've found and what you'd like him to do.

[TD_Madden]

I've got some NOS EL34 Teslas (NOT JJs) that have a really small key...it's VERY easy to put them in wrong.

Speaking of which, I was pulling one out to insert a Bias-Rite and it slipped out of my hand.....$75 bucks down the drain......took me a couple minutes to calm down.

[songwriter7]

Nope sitll nothing.

Well the tube is keyed, although there are two ways it can fit, just only suppose to fit one way though, and yes I checked all the speaker connection and ther is no sound at all. I already put the 5881's back in and they color up fine, just no sound, its driving me nuts. Anyway, thanks for all the replys, if anyone can think of anything else for me to check please just reply again.




Merry Christmas!!!!!!!

[ricach]

Guess I should be more careful then, I'm usually inserting tubes blindly.

As a suggestion, from looking at the schematic, you could tap the Reverb send jack and send it to another amp to see if you're getting sound - this will at least ensure you're getting a signal into the powertube stage. And make sure you've got the reverb switched on.

And as much as I hate to suggest this - first, please make sure the standby switch is in the correct position.

[Steve Conner]

You could have blown one of the fuses when you put your new tubes in wrong. There is usually a second fuse for the high voltage supply. If this one has gone, the tube heaters will still work (they'll "color up" as you put it) but nothing else will happen.

Your KT77s should still be usable, if you're very careful to insert the broken one the right way. The key should only allow the tube to be inserted one way. With the key gone, there are now 8 ways to install it and 7 of them will probably do something nasty to your amp.

[Enzo]

I made up a chart once of what shorted to what for each position of the tube of those 8 ways. COnsider the heater is a short between pins 2 and 7. Turn it one space and now the short is from 3 to 8 - in most amps that shorts B+ to ground. One more and it is now 4 to 1. Oops, screen gets shorted to ground. ETc.

It is very simple to do this exercise, takes a few minutes. Answers that age old question, "Geez, just WHAT did I burn out NOW?"