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    stepped attenuator

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    baddog1946

    Posts: 269
    Join date: 2010-02-03
    Location: Costa Rica

    stepped attenuator

    Post by baddog1946 on Thu Aug 05, 2010 10:24 am

    Hi Bob:
    I'm wondering where the installation info you originally posted for the stepped attenuator went to? I saw the 2 pages briefly on the this site then you said it was moved but I can't find it again. Was it removed or am I looking in the wrong place. I have a 100K 40 step attenuator I got for another amp that may work in there but I want to look at how it is done on the board to make sure I get it right. I tried it for size and it will fit into my base externally mounted so it doesn't have to go inside the chassis.

    Bob Latino
    Admin

    Posts: 1970
    Join date: 2008-11-26
    Location: Massachusetts

    Re: stepped attenuator

    Post by Bob Latino on Thu Aug 05, 2010 11:50 am

    baddog1946 wrote:Hi Bob:
    I'm wondering where the installation info you originally posted for the stepped attenuator went to? I saw the 2 pages briefly on the this site then you said it was moved but I can't find it again. Was it removed or am I looking in the wrong place. I have a 100K 40 step attenuator I got for another amp that may work in there but I want to look at how it is done on the board to make sure I get it right. I tried it for size and it will fit into my base externally mounted so it doesn't have to go inside the chassis.

    Hi Baddog,

    The stepped attenuator instructions to install the attenuator into a stock ST-70 are below ..

    Bob







    baddog1946

    Posts: 269
    Join date: 2010-02-03
    Location: Costa Rica

    Re: stepped attenuator

    Post by baddog1946 on Thu Aug 05, 2010 1:50 pm

    Thanks Bob looks like a piece of cake.

    baddog1946

    Posts: 269
    Join date: 2010-02-03
    Location: Costa Rica

    Re: stepped attenuator

    Post by baddog1946 on Thu Aug 05, 2010 2:36 pm

    hi Bob:
    I forgot to mention that I have an ST-120 with the VTA board and need to know how the ground wire connects.
    The diagram for the stock board doesn't explain the following: Does the ground wire from the attenuator go to the lug on the RCA jack or the board? and how does the ground return to the board if it does? Are there two wires on the lug?

    Bob Latino
    Admin

    Posts: 1970
    Join date: 2008-11-26
    Location: Massachusetts

    Re: stepped attenuator

    Post by Bob Latino on Thu Aug 05, 2010 2:43 pm

    Hi,

    It best to ground the stepped attenuator to the grounding tab on the input jack. The input jack is then grounded to the driver board. You will wind up with two wires connected to the grounding tab on each input jack. One wire will go to the eyelet 3 of the stepped attenuator and one wire will go to a grounding eyelet on the driver board.

    Bob

    baddog1946

    Posts: 269
    Join date: 2010-02-03
    Location: Costa Rica

    attenuator

    Post by baddog1946 on Thu Aug 05, 2010 2:57 pm

    Thanks Bob:
    I'm clear on the connections appreciate the help.
    How is the KT-120 project coming? Are you still playing around with that project?
    I bought a set of them and tried them for a while but will keep them for a spare quad in case I need them. They sound the same as the KT-88's to me.

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