Transformer brand in Mesas

[Boogiebabies]

Mesa used Fender transformers for the Princeton Boost's, but they have had Shumacher make their transformers to their specs for decades.
The EIA 606 code is for Shumacher. The new transformers are EIA 166, but I still think they are a division of Shumacher. The 105,X101,100, 562003,562004 and the old SC-152019B were all made by them.
The only other transformers I have experience with are DeYoung and Dagnall. The DeYoung is in my SLO and the Dagnall is in my 2555 Silver Jubilee. As long as you have the spec, MM, DeYoung, Heyboer and a few other companies can wind you whatever iron you want. MM makes current Mesa style transformers for PT and OT upgrades.

 

[stokes]

At what point (i.e. length of time) will there result permanent damage to an OT or PT when you turn on the amp w/o a load plugged in?

I accidentally turned on my Mark III the other day for about 10 secs before I realized the speaker cable was not plugged into the amp.

Shouldnt be a problem,since the output jack has a "shorting switch" which shorts the jack when no cable is connected to it,and if you werent playing it would be less of a problem with no signal going thru it.But either way it is not advisable to do it too often or for any length of time.

 

[disassembled]

I remember when I bought my first tube head (PV 5150), I didn't know any better and didn't own a cab at the time, I plugged my guitar in turned the amp on cranked the output until I could hear my guitar through the output tranny. I thought this was pretty cool and did it for about 3 minutes and then shut it off. Luckily there were not any ill affects to doing this and the amp still works fine to this day. You can leave your amp turned on all day without a load plugged in but when you start playing through it without a load is when you can pose a serious threat. Mesa even states this in their Power amp manuals if you choose to run only 1 side.

It is VERY hard to blow a quality output tranny. You will know if you caused any damage.

Greg

 

[PolishSasquatch]

haha whaaaat? u dcoudl hear your guiatr thru the output tranny?? thans nuts!

 

[disassembled]

haha whaaaat? u dcoudl hear your guiatr thru the output tranny?? thans nuts!

Well there wasn't a speaker connected so it was either the tubes or the tranny.

Greg

 

[disassembled]

You should try it sometime like the next time you go to GC

 

[Anonymous]

I remember when I bought my first tube head (PV 5150), I didn't know any better and didn't own a cab at the time, I plugged my guitar in turned the amp on cranked the output until I could hear my guitar through the output tranny. I thought this was pretty cool and did it for about 3 minutes and then shut it off. Luckily there were not any ill affects to doing this and the amp still works fine to this day. You can leave your amp turned on all day without a load plugged in but when you start playing through it without a load is when you can pose a serious threat. Mesa even states this in their Power amp manuals if you choose to run only 1 side.

It is VERY hard to blow a quality output tranny. You will know if you caused any damage.

Greg

It's very easy to destroy an output transformer and it can happen in seconds. NEVER take your amp off standby without the correct speaker load connected. Even if you aren't playing thru it the amp can oscillate and take out the output transformer. The fact that your amp still works after playing it with no speaker is a very rare exception and not the rule.
Jerry

 

[stokes]

When in standby there is no high voltage reaching the tubes,only the heaters in the tubes are "on",so no damage can occur with no load in standby.jerryp is right the OT can arc in a matter of seconds,disassembled is very lucky and I find it hard to believe he played the amp for 3 mins. and didnt fry something.