Vintage JTM-50 - S/11295 - 1968 - what it it worth? How to rennovate (if at all)

Discussion in 'Let's Talk Vintage' started by redfish, Apr 6, 2021.

  1. StuC

    StuC Active Member

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    My eyes aren't that good, I can't make it out.
     
    Last edited: Apr 12, 2021
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  2. redfish

    redfish Member

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    wow thats cool ... great detective work
     
  3. redfish

    redfish Member

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  4. redfish

    redfish Member

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    I might have to take it out again to get a good pic ... but this seems to show TG9624 athough the 'G' is a bit too blurry to tell for sure on this pic
     
  5. redfish

    redfish Member

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  6. Ned B

    Ned B Well-Known Member

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    Thanks! I actually remember that post as I was an avid PP member. These are pictures of my SA212 transformers. Are the TG numbers the model and the H numbers the date code? Sorry, Redfish...not intending to hijack your tread!
     

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  7. StuC

    StuC Active Member

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    Yes, H2 would be 1972 if I figured it out correctly. Don't see many 50s with the original PT, does it run hot?
     
  8. alpha al

    alpha al Active Member

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    Not possible if it's "Earthed" (grounded) properly.
     
    Last edited: Apr 10, 2021
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  9. Seanxk

    Seanxk Well-Known Member

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    And it is.....:D

    Red, can you read off any letter codes on the Brown cap please, they will be capitols XXX.
    I have a curious finding, will post later.
     
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  10. redfish

    redfish Member

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    which brown cap Sean?
     
  11. Seanxk

    Seanxk Well-Known Member

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    The .05uf 1000v Hunts cap next to the Bulgin and P/T :)
     
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  12. redfish

    redfish Member

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    I cant read it on any of my pics or video - would have to open her up again - will post what I find when I get round to opening up again
     
    Last edited: Apr 11, 2021
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  13. TAZIN

    TAZIN Well-Known Member

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    Hunts
    A74 (series)
    0.05uF 1000v
    DC Wkg
    H Y? (date code)
     
  14. Ivan H

    Ivan H Active Member

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    I could be way off base here, but through using modern 1,000V (& greater) capacitors, my understanding is that an X rated capacitor will fail closed, or "short" while a Y rated capacitor will fail open. Not at all sure when these designations came into use, but is it possible the H Y designation has something to do with this?
    My JMP50 has this same 1,000V Hunts capacitor mounted between the HT fuse holder & ground. Cheers
     
  15. TAZIN

    TAZIN Well-Known Member

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    I believe the three letter sequence to be a manufacture date code. A similar type date code was used on their electrolytic capacitors. So, if true then I'd expect the code to be either 'H YN' or 'H YD'.
     
  16. StingRay85

    StingRay85 Well-Known Member

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    Great info. Now I need to check my own Partridge codes
     
  17. StuC

    StuC Active Member

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    As TAZIN said, it's a date code. I checked the one in my JTM50 as it's out of the cabinet and it's H TU.
     
    Last edited: Apr 12, 2021
  18. Seanxk

    Seanxk Well-Known Member

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    Yes it's a date code, Stu is it a Hunts or an Erie, is there a type space between those letters or are they equi spaced.
     
  19. StuC

    StuC Active Member

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    Hunts. It's spaced like that: H TU, so tempting to see the H as the year, which would make it week 46 of 1962. It could be week 24 of 1966... I haven't yet found one with a middle digit that would confirm which way around to read these. I've only come across H and Y as the first letter in Marshalls.
     
  20. Seanxk

    Seanxk Well-Known Member

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    Interesting, yes the spacing makes it confusing, but 62 could be from the first batch ( they probably didn't use that many) or more likely 66 I think, let's see what others come up with.
     

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