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    Potted ouput transformers for ST-70?

    JunkyJan
    JunkyJan

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    Post by JunkyJan on Wed Aug 25, 2010 7:51 pm

    Hi Bob and all

    I have lately been seeing potted output transformers in original Dynaco boxes on Ebay. I have never ever seen a ST-70 with potted output transformers though. Do you know anything about it? Also, did they ever make potted power transformers as well? Is there any advantage to having potted transformers, other than it looking neater / less "industrial"?

    -- JunkyJan
    Bc, Canada

    Bob Latino
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    Post by Bob Latino on Wed Aug 25, 2010 9:24 pm

    JunkyJan wrote:Hi Bob and all

    I have lately been seeing potted output transformers in original Dynaco boxes on Ebay. I have never ever seen a ST-70 with potted output transformers though. Do you know anything about it? Also, did they ever make potted power transformers as well? Is there any advantage to having potted transformers, other than it looking neater / less "industrial"?

    -- JunkyJan
    Bc, Canada


    Jan,

    Post a link to the Ebay site that have these transformers so we can see what you mean.

    Bob
    baddog1946
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    Post by baddog1946 on Thu Aug 26, 2010 10:30 am

    They will run hotter in a can
    Luddite
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    Post by Luddite on Thu Aug 26, 2010 11:58 am

    Bob Latino wrote:
    JunkyJan wrote:Hi Bob and all

    I have lately been seeing potted output transformers in original Dynaco boxes on Ebay. I have never ever seen a ST-70 with potted output transformers though. Do you know anything about it? Also, did they ever make potted power transformers as well? Is there any advantage to having potted transformers, other than it looking neater / less "industrial"?

    -- JunkyJan
    Bc, Canada


    Jan,

    Post a link to the Ebay site that have these transformers so we can see what you mean.

    Bob

    Presumably, they could have been Dynaco A-470's, which I believe were potted in cans.

    Charlie
    JunkyJan
    JunkyJan

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    Post by JunkyJan on Thu Aug 26, 2010 1:03 pm

    Luddite wrote:Presumably, they could have been Dynaco A-470's, which I believe were potted in cans.
    Charlie
    Hi Charlie - yes that's right, they were A-470s actually. Unfortunately the posting is gone - must have sold. These were still in their original boxes as well.

    -- 'Jan
    Luddite
    Luddite

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    Post by Luddite on Thu Aug 26, 2010 7:03 pm

    JunkyJan wrote: Hi Charlie - yes that's right, they were A-470s actually. Unfortunately the posting is gone - must have sold. These were still in their original boxes as well.

    -- 'Jan

    Jan,

    I have a PDF file of an old Dynaco transformer catalog. In it they list the specs for the A-470 as well as a schematic for the ST-70 showing A-470's as the output transformers. As far as I know these transformers should work fine. I sent you a PM with my email address. Send me an email and I will send you the PDF.

    Best Regards,
    Charlie
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    GP49

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    Post by GP49 on Fri Aug 27, 2010 1:17 pm

    "Back in the day" Dynaco sold output transformers for scratchbuilders who were contructing their own amplfiers. Those transformers were potted with a DYNACO badge on top of the grey shell.
    baddog1946
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    Post by baddog1946 on Sat Aug 28, 2010 9:02 pm


    Here is the link to the potted trannies

    http://cgi.audiogon.com/cgi-bin/auc.pl?ampstube&1283304667&auc

    cheers
    BADDOG1946

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