Can somebody take a look at this schematic and tell me if this amp has an OPTICAL tremolo?

Discussion in 'Other Amps' started by Gutch220, Jun 17, 2020.

  1. Gutch220

    Gutch220 Well-Known Member

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    You know, the kind with the little light bulb, if so, I"m not seeing it.
    If not, does it use the 12au7 tube at the lower left?

    See....
    upload_2020-6-17_14-18-3.png
     
  2. Micky

    Micky Well-Known Member VIP Member

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    It uses the 12AU7 plus half a 12AX7
     
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  3. Nik Henville

    Nik Henville Well-Known Member Premium Member

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    I can't see a) light bulb, b) light-dependent resistor or similar...

    Like Micky says - a tube and a half does the job.

    Nice amp though - quirky but nice. Good maker disappeared to soon.

    :hippie::pirate::uk:
     
  4. Gutch220

    Gutch220 Well-Known Member

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    What makes it quirky? just wondering.
     
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  5. Micky

    Micky Well-Known Member VIP Member

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    Who said it was quirky?
    Looks similar to the method Fender uses...
     
  6. Gutch220

    Gutch220 Well-Known Member

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    How so?
     
  7. Micky

    Micky Well-Known Member VIP Member

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    Oh I think you mean a CDS cell (like a Fender)?
     
  8. CoyotesGator

    CoyotesGator Well-Known Member

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    .
     
    Last edited: Jun 17, 2020
  9. CoyotesGator

    CoyotesGator Well-Known Member

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  10. CoyotesGator

    CoyotesGator Well-Known Member

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    Apologies for the above, got a case of the stupids tonight.
     
  11. Nik Henville

    Nik Henville Well-Known Member Premium Member

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    In my books - EVERYTHING shouts quirky there...

    [​IMG]
     
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  12. pulsonicsound

    pulsonicsound Well-Known Member

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    beautiful amp! I have one of these from 1972

    everyone says how heavy they are, In all honesty you don’t realise just how heavy they are until you pick one up!

    Has to be the winner of the heaviest valve amp ever designed!!
     
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  13. Gutch220

    Gutch220 Well-Known Member

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    Yes, I own one and it IS heavy, the transformers are huge.
     
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  14. Gutch220

    Gutch220 Well-Known Member

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    ...or a small bulb like a Univibe has.
     
  15. pulsonicsound

    pulsonicsound Well-Known Member

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    Nice! Mines the UX-1501 so no tremolo, it’s supposed to be a pretty intense tremolo!

    I do have the original cab for it as well(also heavy)
     
  16. Gutch220

    Gutch220 Well-Known Member

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    let me know if you ever want to sell it.

    when did you get it?
     
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  17. pulsonicsound

    pulsonicsound Well-Known Member

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    I’ve had it a few months, I bought it to sell to a Jimmy Page nut that I know, he wasn’t interested so it’s in the amp cave gathering dust

    I’m in England, not sure postage would be viable!
     
  18. Gutch220

    Gutch220 Well-Known Member

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    it depends on the price. What would you want for it? Are those amps equipped with a voltage switch to account for 220v or 120v here in the USA? I'm not sure if they built specific models just for overseas voltage.
     
  19. myersbw

    myersbw Well-Known Member

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    To your original question, nope...no opto-isolator like many a Fender...the 12ax7 is configured as an oscillator and the SPEED pot varies the frequency of the oscillator. The output feed the grids of the parallel 12au7 stages...and, as they conduct, they effectively reduce (or short) the signal at the 100K|330K junction to give the effect.
     

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