100W Guys Running EL34s, What PT?

[ChrisM]

100W running a quad of EL34s draw quite a load of heater current. Just wondering what PT you are using to run the EL34s?

[talbany]

Chris

Marshall Style 2204 replacements 470 on the plates w/Full wave bridge..Nice and quiet
Check out Triode Electronics offering good deals on tranny's now

Tony

[ChrisM]

Thanks Tony,

Found a 100W one with 7A filament winding. Unfortunately it is standup style, do you know of any that are the laydown type?

[David Root]

I don't think Marshall used lay down PTs, so the relacements are not laydown. You may be looking at a custom order.

There are a couple of custom order one man shops out there I think, cannot recall any names. Perhaps someone else may.

[ToneMerc]

Thanks Tony,

Found a 100W one with 7A filament winding. Unfortunately it is standup style, do you know of any that are the laydown type?

Marshall laydown power trannies; IIRC they all have the same mounting centers as a Twin PT.

JTM45: 1202-55
JTM50: 1202-118
JTM45/100: 1204-43
Early Plexi's: 1203-80

I had Heyboer make me a custom (1202-55 aka HTS 7119) a few months back for my JTM45 build, I spec'd the heaters @ 6.5A

https://tubeamparchive.com/download/file.php?id=12733

http://marstran.com/InStock.htm

http://www.merrenaudio.com/marshall_transformers


TM

[ToneMerc]

I also had Heyboer make a big honking Twin PT for my BM build.

575mA@340V
8A heaters

[ChrisM]

Ya that's what I would like. I hear Heyboer doesn't do little one off stuff like that anymore though.

[ToneMerc]

Ya that's what I would like. I hear Heyboer doesn't do little one off stuff like that anymore though.

That's news, maybe someone needs to tell Heyboer I ordered a one off transformer last Friday, only one piece.

TM

[ChrisM]

O well, that's only what I've heard.
Thanks...

[talbany]

Chris

You could always go with a Twin style and add a filament transformer and use the 6v taps on the Twin to power relays.. Just a suggestion..Might even be cheaper?
Tony

[fp2000]

For stand-up transformers you can try changing out the bell ends so it becomes a lay-down type. Just have to find the correct size. Just a thought.

[phsyconoodler]

I've taken one bell end off a Marshall transformer and used them in lay-down Ceriatone chassis with no issues.
Works like a dream.Done that with Hammond transformers too.

[ToneMerc]

Ya that's what I would like.

If you are interested in a Twin style, here's the PT that I had Heyboer make for my BM/KT77 build last year. I powered the 4 relays from the 6.3/2A tap. In hindsight, 2A was overkill and 750mA would have been plenty.

HTS-7157-3
Primary: 120 Volts
Secondary: 340 - 0 - 60 - 340 Volts 575 mA
6.3 Volts @ 2 Amps
6.3 Volts CT @ 8 Amps (3.15V-0-3.15V)

TM