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. redfish

    redfish Member

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    pretty much due south
     
  2. neikeel

    neikeel Well-Known Member

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    Ok, I am just East of Cambridge
     
  3. redfish

    redfish Member

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    I used to live in Sawston 10 years ago
     
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  4. Ned B

    Ned B Well-Known Member

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    Take it to Neil.
     
  5. redfish

    redfish Member

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    Last edited: Apr 8, 2021
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  6. Seanxk

    Seanxk Well-Known Member

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    Very very nice indeed, so glad you haven't taken it to Marshall, that Brown Hunt's .05 cap would be thrown out first with no thought or hesitation grrrrr, my dads amp still has it in and it's still connected, round here they call it the Death cap PMSL........
     
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  7. StingRay85

    StingRay85 Well-Known Member

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    Nice amp. I agree take it to Neil for a full inspection :yesway:

    Tubes were last changed in '77. Those 0.68 250V can't be original can they?
     
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  8. redfish

    redfish Member

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    Ive never changed them .... and I brought the amp in the mid-late 70's
     
  9. redfish

    redfish Member

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    StingRay - can you explain to me what you mean by 'Those 0.68 250v' - I am new to all this - cheers - Red

    Are they the big yellow 'cubes' wired in? Why would that be a surprise if they were original?

    How do you know the tubes were last changed in '77? Is your middle name Poirot? :p
     
    Last edited: Apr 8, 2021
  10. StingRay85

    StingRay85 Well-Known Member

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    Indeed the yellow cube caps. They are the Philips successors to the mustard caps. But the varnish on the board looks untouched, so I have no clue (I'm surely not an expert like others here). The tubes mention Xf4 B7 so those are late tubes produced in '77. Since it also has a replaced transformer, it probably underwent a serious repair/maintenance before you bought it.
     
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  11. junk notes

    junk notes Well-Known Member

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    This amp looks converted to a 1987 lead spec. (V1B 2200pf).
    I would leave the Philips chicklets, they are excellent caps! Perhaps replace with Mustards if a future sale for top dollar.
    I really cannot tell effectively what the anomalies are, because of the insulating paint, as some are obvious. Slider bias - awesome mojo :)
     
  12. kuli

    kuli Active Member

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    Well I would certainly remove that death cap, it is call that because if it leaks and if in some situation you would be the ground, through your guitar or a microphone, well it could kill you..
     
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  13. StuC

    StuC Active Member

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    Those chicklet caps are original. .
     
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  14. neikeel

    neikeel Well-Known Member

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    Ok
    Original mid 68 lead amp
    Replaced OT and fuses
    That cap is not a death cap, just a snubber inch the HT. Hunts have a bad rep ( justified most will say) for failure so probably ideal to replace (internal short sends HT to ground - ie chassis)
    It has Heath-Robinson screen resistors that needs to be done properly.
    Really nice amp. If original OT worth over £4k (GBP) that is
     
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  15. redfish

    redfish Member

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    What is OT?
     
  16. neikeel

    neikeel Well-Known Member

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    output transformer
    I actually have an original working one here.
     
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  17. redfish

    redfish Member

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  18. neikeel

    neikeel Well-Known Member

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    Looks like D Macloud or similar.
    Not J Marshall.
     
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  19. Seanxk

    Seanxk Well-Known Member

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    Exactly.

    Here's a Feb 69, those fuse holders look the same.
    IMG_1969.jpg
     
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  20. Seanxk

    Seanxk Well-Known Member

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    Here's S/11930


    IMG_1943.jpg
     
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