You would be correct. The PT here is stamped 30048-2 (352644) and one of the OTs is stamped 32021-4 (352631). I'm guessing the first is a model and the second number is a serial number.
Is it powered by 7591As?
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Transformer ID
Thank you Captn Dave!!!! You made my month!! So now I know it is Eico Iron.
From what I can deduce, using info from this site:
EIA Codes
My PT was made by Stancor in *2 year in the 52nd week
My OPT was made by Stancor in *3 year in the 9th week
Your PT was made by Essex in *6 year in the 44th week
your OPT was made by Essex in*6 year in the 31st week
I would guess yours are newer versions than mine because of the higher suffix numbers
on the part numbers.
My amp is a custom power amp using this iron which has been thru at least two
versions. In the first case it did use 7591's. But this labeling has been crudely covered
in the existing state. In its present state it supposedly was using EL34's and was labeled as Model 20/20 and Class A. It may be 20 years old(or more). It is a well made item
and I now need to find a schematic that it might have been made from.
Thanks for your help. I sincerely appreciate it.
Victoria
Thank you Captn Dave!!!! You made my month!! So now I know it is Eico Iron.
From what I can deduce, using info from this site:
EIA Codes
My PT was made by Stancor in *2 year in the 52nd week
My OPT was made by Stancor in *3 year in the 9th week
Your PT was made by Essex in *6 year in the 44th week
your OPT was made by Essex in*6 year in the 31st week
I would guess yours are newer versions than mine because of the higher suffix numbers
on the part numbers.
My amp is a custom power amp using this iron which has been thru at least two
versions. In the first case it did use 7591's. But this labeling has been crudely covered
in the existing state. In its present state it supposedly was using EL34's and was labeled as Model 20/20 and Class A. It may be 20 years old(or more). It is a well made item
and I now need to find a schematic that it might have been made from.
Thanks for your help. I sincerely appreciate it.
Victoria
Nope. No UL taps. I imagine you will have to draw out that schematic yourself. Is it a power amp or an integrated now?
That's interesting about the codes. Where did you find that info?
I have read a couple of blogs about running the OTs at much higher power than their original application would suggest advisable, without problems. So it does not surprise me to see EL34s used with the OT. What does surprise me is to see the EICO PT supplying the heater current to four hungry EL34s. Since an EL34 uses twice the heater current as the 7591A, it had occurred to me that the PT together with a single OT would make a good mono project. Either that or add another heater transformer for the second set of power tubes or perhaps operate the small signal tubes off a DC supply from a second PT.
I imagine that your PT is operating without the phono stage and the tone stage in that application which certainly is a mitigating factor, but consider that you would need to kill off about eleven pawns to feed the king and queen. I wonder how long the HT winding will hold up under that load. Something to consider.
That's interesting about the codes. Where did you find that info?
I have read a couple of blogs about running the OTs at much higher power than their original application would suggest advisable, without problems. So it does not surprise me to see EL34s used with the OT. What does surprise me is to see the EICO PT supplying the heater current to four hungry EL34s. Since an EL34 uses twice the heater current as the 7591A, it had occurred to me that the PT together with a single OT would make a good mono project. Either that or add another heater transformer for the second set of power tubes or perhaps operate the small signal tubes off a DC supply from a second PT.
I imagine that your PT is operating without the phono stage and the tone stage in that application which certainly is a mitigating factor, but consider that you would need to kill off about eleven pawns to feed the king and queen. I wonder how long the HT winding will hold up under that load. Something to consider.
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Captn Dave said:
"That's interesting about the codes. Where did you find that info?"
This is the link to the site with the info: EIA Codes
It was shown in my previous post as "EIA Codes" and was a hot link.
This link:
diytube.com :: View Forum - eiclone
Puts you on the "Eiclone" portion of the DIYTUBE.COM site.
These guys sell a pc board used to make a monoblock using
Eico iron just like you were thinking.They apparently are superb!!
The resultant monos are compared to Dyna Mark III's here:
diytube.com :: View topic - Sonics of the Eiclone vs the MKIII
Would have nice to have the UL taps.
I will see what I can do for pics. I've never done it on this site before and I can't find a "how to" article.
Thanks again for you help. Victoria
"That's interesting about the codes. Where did you find that info?"
This is the link to the site with the info: EIA Codes
It was shown in my previous post as "EIA Codes" and was a hot link.
This link:
diytube.com :: View Forum - eiclone
Puts you on the "Eiclone" portion of the DIYTUBE.COM site.
These guys sell a pc board used to make a monoblock using
Eico iron just like you were thinking.They apparently are superb!!
The resultant monos are compared to Dyna Mark III's here:
diytube.com :: View topic - Sonics of the Eiclone vs the MKIII
Would have nice to have the UL taps.
I will see what I can do for pics. I've never done it on this site before and I can't find a "how to" article.
Thanks again for you help. Victoria
Yeah, I see it now.
To post a photo, you take a photo and store it on you desktop or somewhere else where you can find it. Then, when you reply, you look below the Message box to Attach Files and click on "Manage Attachments". You then click on Choose File, find that file on your drive and the click upload.
That it.
To post a photo, you take a photo and store it on you desktop or somewhere else where you can find it. Then, when you reply, you look below the Message box to Attach Files and click on "Manage Attachments". You then click on Choose File, find that file on your drive and the click upload.
That it.
I was looking at it after taking the pictures and there are only 6 octal sockets showing. I knew that, but the implication of it had not sunk in.There isn't a rectifier tube, so the power supply is all buried underneath. I'm going to have to make a schematic of the amp to understand what is happening. Is there a sensible way to do that or do you just dive in
and stay away from the fridge?
A another problem I have now is that I need to find (be told) what *Octal* tube (or tubes} can go in front of each pair of the 6P3S-E's output tubes (I propose to use).
This tube would be the equivalent of the 6AN8's in front of the KT88 in a Dyna Mark III.
The Mark III is a 6 tube(ignoring the rectifier) power amp also.
I believe it is OK to discuss this amp on this thread as it is about the use of EICO
iron.
Is there a site with an English data sheet for the 6P3S-E ? I haven't found one yet.
Any help would be sincerely appreciated.
Thanks, Victoria
and stay away from the fridge?
A another problem I have now is that I need to find (be told) what *Octal* tube (or tubes} can go in front of each pair of the 6P3S-E's output tubes (I propose to use).
This tube would be the equivalent of the 6AN8's in front of the KT88 in a Dyna Mark III.
The Mark III is a 6 tube(ignoring the rectifier) power amp also.
I believe it is OK to discuss this amp on this thread as it is about the use of EICO
iron.
Is there a site with an English data sheet for the 6P3S-E ? I haven't found one yet.
Any help would be sincerely appreciated.
Thanks, Victoria
Yours is a third order threadjack so I wouldn't be too concerned about that. But if you were to start a fresh thread it might get wider viewing. Up to you.
I start by drawing the power supply on one sheet, the phase splitters and power tubes on a second and the front end on a third. That compartmentalizes things and makes the inevitable revisions less tedious.
I don't have a ready answer for you on the phase splitter or datasheet. Once you get things drawn, the selection of a phase splitter will be easier. LTPs with CCS are very popular around here right now and might be worth investigating.
I start by drawing the power supply on one sheet, the phase splitters and power tubes on a second and the front end on a third. That compartmentalizes things and makes the inevitable revisions less tedious.
I don't have a ready answer for you on the phase splitter or datasheet. Once you get things drawn, the selection of a phase splitter will be easier. LTPs with CCS are very popular around here right now and might be worth investigating.
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