Home Forums Vintage EHX Does anyone have internal pics of an Attack Decay?

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  • #81335
    Fender&EHX4ever
    Moderator

    I’m not getting any signal, bypassed or engaged.

    It’s obvious that some repairs were done to it prior to my purchasing it. You can tell because some of the tracing at the top was peeled off, so a white wire with blue strips was soldered on to bridge the gap.

    Can anyone tell me if this appears to be wired correctly?

    To see the photos in full screen, just right click on the photo and say open in new window:

    5428667481_bb1122edab_b.jpg

    5428667007_fc24cd1d01_b.jpg

    #114202
    Fender&EHX4ever
    Moderator

    Here is a list of the ICs in this thing:

    CD4013BE (RCA-001)

    RC455873 (C8008)

    MN3007

    CD4047BE (RCA 927)

    CD4066BE (RCA 836)

    CA311G (RCA 849)

    XC NC1458P

    CA3080E (RCA 932 and RCA 927)

    LM741CN

    RCA4558N (C030)

    Any of these seem out of place?

    #191984
    Carlsoti
    Participant

    Any chance you still have this pedal? I’ve got one with a EX2500A board. There are differences between the two boards.

    #196942
    Jazz Padd
    Participant

    Here’s the innards of my Attack Decay:

    E11331-DA-4-FD6-408-C-BC5-A-6-A3842-BB3-F9-B

    Hoping it’s somehow helpful.

    • This reply was modified 1 year, 10 months ago by Jazz Padd.
    #196951
    Carlsoti
    Participant

    With Mr. Davis focusing his time on developing new pedals for a different brand, this thread may become more and more important in keeping some of these rare old pedals going. The AD I was working on was given back to it’s owner some time ago.
    I ended up having to reach out to some others for more input, as I was beating my head against the wall trying to figure out what was causing the “no effect” problem I was having. Instead of taking the time to look at what each part of the circuit was doing, I was just looking for bad parts, etc. Bad form on my part. When I was signal tracing with my o-scope, I was just picking up noise, not signal. Initially, it was a bad coupling cap after the first 4558 stage that was tripping me up. Once that bad coupling cap was figured out, I had a bit of an “Ah HA!” moment, and delved into what each ICs function was and things moved along quicker. Replaced a few ICs, then replaced the tants and ‘lytics, as a couple new chips went bad. After that, I spent a lot of time trying to get rid of extra noise that I thought was an indication something still wasn’t right. A few folks pointed out that, due to the compression early in the effect, they were just naturally noisy, and likely couldn’t be made quieter without significant modification.

    #197520
    Memory_Man
    Participant

    Anyone knows what the trimpot does inside?
    Just recieved a vintage Attack Decay and was wandering if anybody knows what the trimpot inside does?
    With the Micro Synth its essential to set it right to the players guitar and playing style and was hoping this could be the same with the AD?

    #197521
    Memory_Man
    Participant

    Just found a schematic and found out the AD has 2 trimpots, one for gain & a bias for the MN3007(?).

    Happy to measure voltages if it can help to repair another vintage Attack Decay!

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