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  • October 6, 2009 at 8:38 pm #79090
    ibbluesman
    Member

    I have vintage deluxe big muff, the one with the blend switch. The compressor works but the fuzz quit working. I am a electronics tech. Does any one have a schematic of this model. Any info would be helpful. It’s 78 model,that I bought new, with #3053c on the C.B. I found schematic online but it is for the transistor model and mine has IC chips in it. I am suspecting that one of the 4558 IC’s has blown out. But there are no visable signs of any blown or burned components.

    October 7, 2009 at 8:39 pm #102084
    Mr.Grim
    Member

    try going to http://www.ronsound.com/ he makes reproductions, does repairs( i think hes currently over booked) and he also sells schematics for EH pedals, i myself just purchased 2 from him for my “Y Triggered Filter” and “The Silencer”.

    October 9, 2009 at 5:43 am #102111
    ibbluesman
    Member

    Thanks for the info. I went to the site and found the schematic that I needed listed. He has a good many differant ones available. It cost 5 bucks and he emailed it to me. Very fast service. He also fixes effects and is back logged for 2 months. I would recomend it any needing effects schematics. Not just EHX but many different kinds. He also has amp schematics. Thanks for the reply and the info. I will post what I find wrong with my Deluxe Big Muff 78 blend sw. model, in case any one else is having the same problem. My fuzz stopped fuzzing all though you could still hear the tone section working. But the fuzz volume and fuzz sustain quite working. It seems that the compresser is still working.

    October 19, 2009 at 1:28 am #102405
    ibbluesman
    Member

    I fixed the Deluxe Big Muff PI This unit was made in 1978. It was one of the 4558 IC Chips just as I had suspected. I decided to replace all 4 of the 4558 IC Chips with the famous JRC4558 used in the TS-808 mods. All of the IC’s are soldered in as opposed to the kind that use sockets that the IC’s just plug into. So this is not a mod for inexperienced to try. I was trained by the US Navy and the Air Force on soldering. It could be very easy to over heat a IC chip by leaving the soldering iron on it for to long. I found 2 legs on one of the origanal chips shorted out to each other. I think this is what caused the failure in the first place. It’s hard to beleive that it came from the factory this way, but it did. The Big Muff failed way back in the early 90’s, I put up for years before pulling it out and trying to fix it. I never realy liked the sound of the unit until now. It sounds killer with the new chips installed.

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