50W plexi transformer specifications

[krusty]

Hi there,
anyone has (knows) the specification for power and output transformer for
50W plexi?
I know that power transformer is
1202-118
and output transformer is
784 - 139
and the choke is the C1999
so here are my questions
1) what are the secondaries voltages for power transformer and the current the transformer can handle?
I suppose should be something like (the primary voltage is for europe)
230V -> 360 - 0 - 360 for B+ secondary but how many mA ?
-> 3.15 - 0 - 3.15 for the heaters but how many mA in total?
Is the original transformer secondary center tapped?
correct?
2) what is the primary impedance of the 784-139 ? 3.4KOhm? What is the max current for the primary?
3) how many Henry is the filter Choke and how many mA can it handle?

Thanks for your answer as I cannot find these specifications/data sheet searching with google.
My Idea is to order some custom transformer as close as I can to my home town in order to save on shipping
Thanks again.
Krusty

[mc_guitar]

Hello Krusty,

I don't think saving on shipping is the right way to go... The transformers have an enormous impact on the sound. You would not want to limit your amp there!
There are a lot of good suppliers all over the world. So where are you from? Maybe we can help to find most reasonable priced supplier for you.

Cheers Michael

[krusty]

Hello Krusty,

The transformers have an enormous impact on the sound. You would not want to limit your amp there!
There are a lot of good suppliers all over the world. So where are you from? Maybe we can help to find most reasonable priced supplier for you.

Cheers Michael

Hi Michael
and thanks for your reply.
You are perfectly right, transformer are the "core" of the amp.
I have my transformer supplier here in Italy, but I have to give specifications in order to have those beauties.
this Is the reason why I'm looking for the specifications in order to have my "custom" transformer made by my supplier.
Can you please provide me the informations? as I cannot find them,
I just found that for output transformer primary impedance is 4k..but no other data so far.
Anyway any other suggestion is still appreciated. (also a list of supplier of "good" transformer in Europe ) so I can evaluate different solutions
Thanks
Krusty

[mc_guitar]

Hello,

Some premium Transformers from Germany e.g.

http://www.tubeampdoctor.com" onclick="window.open(this.href);return false;
http://www.tubetown.de" onclick="window.open(this.href);return false;
http://www.ig-transformatoren.de" onclick="window.open(this.href);return false;
http://www.welter-electronic.de" onclick="window.open(this.href);return false;
etc.

or in Italy:

http://www.inmadout.com" onclick="window.open(this.href);return false;

Some more detailed Info can be found on any of these pages!

Cheers Michael

[krusty]

Hello,

or in Italy:

http://www.inmadout.com" onclick="window.open(this.href);return false;

Some more detailed Info can be found on any of these pages!

Cheers Michael

Thanks a Lot Michael,
but haven't you got transformers specs too?
So I can ask for a custom quotation from other suppliers as well?
Thanks.
Krusty

[neikeel]

Tend to be closely guarded secrets.

Lam sizes, types. material, bobbin sizes and materials, all go into the mix.

The relatively cheap Drakes and Dagnalls we love were all different (like the PAFS), good ones and bad ones.

The guys that sell these teardown trannies to get the correct specs and replicate them. Look on Marstran site (and forum) and you will see what I mean.

I buy trannies from Brian at Marstran and George here because I know what I am getting and that it will produce the goods for me. I have been bitten by the 'cheap' transformer mistake and will not do it again

[mc_guitar]

Tend to be closely guarded secrets.

Lam sizes, types. material, bobbin sizes and materials, all go into the mix.

The relatively cheap Drakes and Dagnalls we love were all different (like the PAFS), good ones and bad ones.

The guys that sell these teardown trannies to get the correct specs and replicate them. Look on Marstran site (and forum) and you will see what I mean.

I buy trannies from Brian at Marstran and George here because I know what I am getting and that it will produce the goods for me. I have been bitten by the 'cheap' transformer mistake and will not do it again

Thats exactly what I was trying to say!

Cheers Michael

[krusty]

Thats exactly what I was trying to say!

Cheers Michael

I perfeclty agree with what you both said guys...
but has anyone the specs?
I mean electrical specifications, not mechanical or design specifications. (I saw the reverse enginering they does on transformer on Mastran site...but I haven't find electrical specs (voltages, impendance and so on)
As I said I have a "supplier" that can build some transformer for me, but I have to give him the specification in order to have them built and to have a quotation.
So I can try with this and then let my ear judge the result!
Hope you can help me!!
Krusty

[mc_guitar]

Hello Krusty,

The Voltages and Impedances can be found on several sites in the Net.

Hammond Marshall 100W PT
Hammond Marshall 100W 4xEL34 OT etc.

Cheers Michael

[arledgsc]

I don't think you are going to find specific information on how each transformer is built. More likely general specifications for impedance, voltage, current, power, turns ratio, and/or inductance for user connection and use. There's a lot of other things rolled into transformer construction like bobbin type/ size; lamination size, number, material; wire gauge/ type; how the transformer is wound, etc. It I had a transformer for sale contruction information would certainly be proprietary.

One question... Why do you want to wind your own versus buying one that is recommended and tried? Seems like a one off transformer would be expensive and no guarantees it will even work without many tweaks....

[krusty]

More likely general specifications for impedance, voltage, current, power, turns ratio, and/or inductance for user connection and use. \

Well these are the data I'm looking for as I told I don't want to steal any "secret"...but no good luck so far..

I wish someone can give me ELECTRICAL specs for
1202-118 (voltages) on the secondary and current
784-139 (primary impedance)

What are the electrical specifications of these transformer or of the ones sold with Metroamp Kit?
I don't want a "generic" replacement as I can find on the hammond website...I was looking for specification of those specific models...used in plexi

One question... Why do you want to wind your own versus buying one that is recommended and tried? Seems like a one off transformer would be expensive and no guarantees it will even work without many tweaks....

I have my supplier who can build very good quality transformer but I have to give him electrical specification..so I'm asking for help.
I don't think it's so weird...is it for you?

Thanks again for your help
Krusty

[Coot Boy]

Well I can't believe you still don't have any specs so I'll post these.
The specs here are for Magnetic Components 50W Marshall set which I have used with great results..
PT, Seconday= 345 0 345 @ 150mA----- 6.3V CT @ 5A
OT imp = 3.6k
Choke, 5H @120mA DCR = 115 ohms.
HTH