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    Inputs on MK IV - isolated from chassis?



    Inputs on MK IV - isolated from chassis?

    Post by Guest on Sun Jul 03, 2011 12:55 am

    Are the inputs on the MK IV"s isolated from the chassis? I put in new RCA's and use isolation washers, and am not sure why. Looking at the old OEM RCA's, they appear to have been connected directly to the chassis, no isolation..

    Bob Latino

    Posts : 2383
    Join date : 2008-11-26
    Location : Massachusetts

    Re: Inputs on MK IV - isolated from chassis?

    Post by Bob Latino on Sun Jul 03, 2011 7:29 am

    Hi Michael,

    Those input jacks should not be grounded to the chassis at the point that they are attached to the chassis. Those input jacks should have an insulation washer to prevent them from touching the chassis at the attachment point. The original OEM Dynaco input jack should have been mounted on a bakelite washer to prevent the jack from touching the chassis. There should be a ground wire running from the grounding tab of the input jack to eyelet #1 on the PC-4 driver board.


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