do you guys know anything about tube echoplexes?

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by brad347, Aug 3, 2006.


  1. brad347

    brad347 Member

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    If so, then i've got a problem. I just got an original EP-2 for 300 bux because it has this one issue... It does not record over your old material, it is like stuck in something like the "sound on sound" mode of the later solid-state echoplexes. In other words, it just keeps playing back your old material instead of recording over it and working as an echo should... very annoying. Other than that it works fine. Electrolytics look to have just been replaced. Brand new fullltone tape cartridge, and I cleaned the entire tape travel path including pinch roller with teh proper cleaning stuff and demagnitized the heads thoroughly. What's up? Any ideas?
     
  2. Fuchsaudio

    Fuchsaudio Member

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    Sounds like your bias oscillator is not working, you have a bad erase head or a wire off. Any technician (perhaps an older technician...lol) who is familiar with tubes and/or tape recorders in general, should be able to figure it out. Check if the erase head wires are attached too. Look at the heads with a magnifying glass too. Sometimes a big hunk of "tape snot" can clog a head, despite cleanings.
     
  3. brad347

    brad347 Member

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    andy this is brad, the guy whose brown super and deluxe nonreverb you worked on. If I can't get it going would you take a look at it for me? How much?

    Someone has replaced the PT and futzed around with some wires in there it is obvious. Looks like they did a good enough job but i'm tracing it out with the schem. right now to make sure all their math is right. But i'm no guru so I might not be able to find it.
     
  4. brad347

    brad347 Member

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    PS, if the erase head is shot, is a replacement find-able or is this thing a 'parts donor?'

    Maybe mike battle could hook me up?
     
  5. Fuchsaudio

    Fuchsaudio Member

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    LOL. Didn't notice it was you. I'd take a quickie look at it for you, no idea about parts availability, but it should take ten minutes to at-least get some idea of what MIGHT be the problem. Give me a buzz at the shop in the AM.
     
  6. brad347

    brad347 Member

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    ok andy thanks, however I might wait until I get my new 6C4 tube in the mail. I just ordered one because I don't have a spare laying around at least i don't think I do... i'll check the basement. Unless you have an extra laying around to sub in maybe it's best to wait until I eliminate that variable, right? thanks man!

    bw
     
  7. Fuchsaudio

    Fuchsaudio Member

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    Well, according to the schematic, that's the bias oscillator. If it ain't there, you'd have exactly the problem your seeing. Let me know if the tube fixes things up.
     
  8. brad347

    brad347 Member

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    found two spare 6C4s in the basement. There was also one 6C4 in it when I got it that looked old and questionable. ˆ tried all 3 6C4s just now to no avail. I'll call you in the morning!
     
  9. itgoesto11uc

    itgoesto11uc Member

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    If it has the sound on sound switch, it could be a bad switch.
     
  10. brad347

    brad347 Member

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    Actually, I'm going to try cleaning the 6C4 socket just in case. But if that fails I'll call ya.

    edit: cleaned it, no difference. Call you in the AM.
     
  11. brad347

    brad347 Member

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    this model does not have the sound on sound switch. Thanks for the good idea though!
     
  12. itgoesto11uc

    itgoesto11uc Member

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    You're welcome. The sound on sound switch failed on a solid state EP-3 I had once and it demonstrated the same behaviour.
     

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