Low heater voltage 124 classic (FIXED)

[FUCHSAUDIO]

Does it have a dual primary that might be wired wrong ?

[dcribbs1412]

The voltmeter has a new & good battery in it correct?

I only mention that because of getting "off" readings on an amp with a voltmeter (thinking it was the PT) only find the battery was bad. I've seen others on amp forums post doing the same mistake.

Just trying to rule that concern out.

With respect, 10thtx

I will check it
other readings seem in the correct range so I'm not sure...but

Does it have a dual primary that might be wired wrong ?

No sir....Its a MC Twin PT 40-18004

Darin

[FUCHSAUDIO]

If all the other voltages are correct, then clearly you have a defective transformer they should be willing to replace.

[dcribbs1412]

If all the other voltages are correct, then clearly you have a defective transformer they should be willing to replace.

Thank you
I have contacted Chad at Triode.
hope to get this resolved ASAP....Will report back
I greatly appreciate everyone's time

Darin

[dcribbs1412]

The voltmeter has a new & good battery in it correct?

I only mention that because of getting "off" readings on an amp with a voltmeter (thinking it was the PT) only find the battery was bad. I've seen others on amp forums post doing the same mistake.

Just trying to rule that concern out.

With respect, 10thtx

Sincerest apologies...this evening changed my battery in my meter and bingo 7.1V AC. I let Chad @ Triode know
...found a broken octal socket also...forgot some important stuff at work...wife is asking what my problem is...I hope this build doesn't hurt me...I need a drink...sorry if I wasted you're time and for this rant...


Darin

[sonicmojo]

Sincerest apologies...this evening changed my battery in my meter and bingo 7.1V AC. I let Chad @ Triode know
...found a broken octal socket also...forgot some important stuff at work...wife is asking what my problem is...I hope this build doesn't hurt me...I need a drink...sorry if I wasted you're time and for this rant...


Darin

Don't worry about it and I'm glad you sorted it out although that sounds a little bit high now. You definitely want to try another meter. We've all been there at some point and that's why these discussions are so helpful. I put a quality meter on my Santa list this year.

[ChrisM]

It will come down when it has a load (tubes).

[FUCHSAUDIO]

It's happened to me....when I don't notice my Fluke meter battery indicator is on, the readings start getting wacky. Good for you ! You found it.

[talbany]

Darin
IMO you are not an expieranced builder until you do at least one of the following..If your real experienced you have done them all!!

Trip over your guitar cord only to look back and see the amp hit the floor.
Shock yourself
Smoke a Part
Begin to troubleshoot an amp that is not plugged in (somewhere)
Wire an Output transformer backwards
Have to re-wire your heaters
Install your parts on the wrong side of the board you just cut
Spend most of the day tracking down a strange noise only to find it's coming from your Iron or computer or a light sitting next to the amp
Red Plating a fresh Matched quad
The obvious..Throw an amp a tool or your computer across the shop floor ..(I threw a chair once..LOL)..
Developing a rare form of Tourette syndrome..(shouting profanity at inanimate objects)
Have a shipper mangle an amp you just spent a week building
Have to mod a perfectly good sounding amp for more gain
Do a Mercury Magnetics upgrade to a Tiny Terror..(I call them Terrier)
And of coarse forget to change the battery on your test gear..

Welcome to the club..

Tony

[dcribbs1412]

Darin
IMO you are not an expieranced builder until you do at least one of the following..If your real experienced you have done them all!!

Trip over your guitar cord only to look back and see the amp hit the floor.
Shock yourself
Smoke a Part
Begin to troubleshoot an amp that is not plugged in (somewhere)
Wire an Output transformer backwards
Have to re-wire your heaters
Install your parts on the wrong side of the board you just cut
Spend most of the day tracking down a strange noise only to find it's coming from your Iron or computer or a light sitting next to the amp
Red Plating a fresh Matched quad
The obvious..Throw an amp a tool or your computer across the shop floor ..(I threw a chair once..LOL)..
Developing a rare form of Tourette syndrome..(shouting profanity at inanimate objects)
Have a shipper mangle an amp you just spent a week building
Have to mod a perfectly good sounding amp for more gain
Do a Mercury Magnetics upgrade to a Tiny Terror..(I call them Terrier)
And of coarse forget to change the battery on your test gear..

Welcome to the club..

Tony

Thanks guys
I'm still having fun...Tony that is some good stuff...I may print your list and check off as I go.
I really appreciate you guys and your willingness to share your experience.

Well on to my next hiccup...not sure if I should start a new thread..
but...
with power tubes in I throw off standby and there is a buzz
and the bias is wacked only sweeps about 6mv...buzz increases as I go up...replaced bias pot...check all grounds/wiring not sure where to go?
neg voltage on bias pot is from left to right -57 -43 -43

Darin

[wjdunham]

Spent a few hours two weeks ago debugging an amp that had a bad distortion, and kept red-plating the power tubes - only to find out that the speaker cable was not plugged fully in to the cabinet. Sound was coming out, but the impedance was way off (probably shorted). Had a beer after that one...
Bill

[dcribbs1412]

Thanks Bill
will add that to the check list


Darin

[Structo]

The trick to gaining experience is to remember your mistakes and not repeat them.
But as you age it seems the memory is the first to go, yes really.

One time I had just done a handful of mods and tweaks on my D'lite.
I plug everything in making sure the speaker is plugged in well.
Turn it on the tubes glow, flip the standby switch to play and nada, zip, finito, nothing, etc.....

Not a sound.

After exhausting every troubleshooting technique I knew and a few from friends I was sure that I had somehow blown the output transformer.
I was in the process of taking the OT out of the amp when I had a thought and swapped out the speaker cable.....
It seems the speaker cable had taken that moment to get a break in it and fail.
It was a cheap Marshall cable, with molded ends like the one that comes with their amps.
I threw that thing so hard it left marks on a wall.

I immediately bought three nice speaker cables from the Lavaman.

So be sure to consider things that might even be a coincidence and not likely, because strange things do happen.

[LeftyStrat]

Trip over your guitar cord only to look back and see the amp hit the floor.
Shock yourself

How about a customer tripping over the guitar cord, and you shock yourself grabbing the chassis to keep it from hitting the floor.

My test guitar chord is now firmly attached to the bench.

[Structo]

Ouch!

Who would have thought?

But it will never happen again, good on you.