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    new quad cap, on to the driver now,

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    dmagazz

    Posts : 140
    Join date : 2018-06-20
    Age : 51
    Location : new fairf, ct

    new quad cap, on to the driver now,

    Post by dmagazz on Thu Jun 28, 2018 6:40 pm

    ok, got some of my caps today,
    a 80,40,30,20, 525v
    and 10 caps for the original driver board,
    does anyone recommend NOT changing any of those for some reason?
    old

    new


    audiobill

    Posts : 366
    Join date : 2014-03-13
    Location : Philadelphia

    Re: new quad cap, on to the driver now,

    Post by audiobill on Thu Jun 28, 2018 6:54 pm

    You should just replace the whole driver board with Roy's.....
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    dmagazz

    Posts : 140
    Join date : 2018-06-20
    Age : 51
    Location : new fairf, ct

    Re: new quad cap, on to the driver now,

    Post by dmagazz on Thu Jun 28, 2018 7:13 pm

    thanks, who's roy? ill check it out, but for now im
    just changin caps for now. with same values. but id seen someone said leave the domino for some reason.and someone else had said leave the little 82 pico's. but did not say why.
    got these from dynacoparts
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    Dave_in_Va

    Posts : 244
    Join date : 2013-04-02

    Re: new quad cap, on to the driver now,

    Post by Dave_in_Va on Thu Jun 28, 2018 8:28 pm

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    dmagazz

    Posts : 140
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    Re: new quad cap, on to the driver now,

    Post by dmagazz on Thu Jun 28, 2018 8:49 pm


    Dave_in Va
    thanks man, is seen that. been all over that page with a monster wish list!.

    i just got done with the driver caps too.Wink couldnt wait

    i will possibly get that board eventually, but for now i just want to refresh mine
    top and bottom of the board
    i went and resoldered some sketchy looking points too.


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    WLT

    Posts : 54
    Join date : 2013-07-13
    Location : Rochester NY

    Re: new quad cap, on to the driver now,

    Post by WLT on Sat Jul 07, 2018 9:16 am

    Nice job. It looks great. You can always replace the board but you have your board looking good for now. I did the same but also went thru the resistors to check their values. Many of the old carbon comps will drift. And not match channel to channel either. I decided to replace several of them and now both sides have similar operating voltages. They sound great as well. No need for a new board for me.
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    dmagazz

    Posts : 140
    Join date : 2018-06-20
    Age : 51
    Location : new fairf, ct

    Re: new quad cap, on to the driver now,

    Post by dmagazz on Sat Jul 07, 2018 12:46 pm

    thanks.
    i figure the same. knowing what heat may do to the solder traces on threse old boards kept me from removing ends of resistors to check them.and its possible the old carbon might change value with the heat or the movement of the lead in the bond as well. so. im leaving them to continue their job.
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    WLT

    Posts : 54
    Join date : 2013-07-13
    Location : Rochester NY

    Re: new quad cap, on to the driver now,

    Post by WLT on Sun Jul 08, 2018 9:03 am

    For the most part I do not un-solder them. Obviously several will have incorrect readings this way. You can find the ones on the stock schematic that are in parallel with others that will give erroneous readings. The rest will test fairly well. Most of the resistors have a high value so they actually read as if they were open air tested. In particular the voltage amplifier plate and screen grid resistors and the phase splitter plate/cathode resistors. They all should be matched or very close to the schematic value.

    The overall feedback resistor and the voltage amplifier cathode resistors will influence each other. If each channel measures close to each other I let them go. If they are off I un-solder them for further testing.
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    dmagazz

    Posts : 140
    Join date : 2018-06-20
    Age : 51
    Location : new fairf, ct

    Re: new quad cap, on to the driver now,

    Post by dmagazz on Sun Jul 08, 2018 3:28 pm

    thanks for the insight. maybe ill compare them later today. right now.. im enjoying them Smile
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    ttownscott

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    Join date : 2018-07-31
    Age : 54
    Location : Tacoma, WA

    Re: new quad cap, on to the driver now,

    Post by ttownscott on Sun Aug 12, 2018 3:01 pm

    Thanks for your postings. I'm right behind you in my amp rebuild.
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    dmagazz

    Posts : 140
    Join date : 2018-06-20
    Age : 51
    Location : new fairf, ct

    Re: new quad cap, on to the driver now,

    Post by dmagazz on Sun Aug 12, 2018 3:38 pm

    enjoy. i think if i was to do anything different id would have used sprague caps(they are a little bigger). but it worked out sounding very nice! im happy with it. im gonna be working on an extension that mounts to the back pretty soon. it adds 4 lugs and a toggle to enable a center speaker to be used.just havent settled on if i want to use old school screw terminals(as the mod would have been made in the 60's) or newer style more robust connectors.

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    Re: new quad cap, on to the driver now,

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