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    ST 120 VTA driver board

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    Maintarget

    Posts: 106
    Join date: 2013-02-10

    ST 120 VTA driver board

    Post by Maintarget on Mon Mar 25, 2013 9:58 pm

    Any problems with mounting all the capacitors on the bottom of the PCB?
    All resistor the three tube sockets and the four bias pots would be on the top of the PCB.
    Why?
    I'm building a custom enclosure for a ST 120 and want to flush mount the driver tube sockets on the bottom side of the enclosure by mounting socket on a sub board so no fasteners would be visible on the enclosure.
    Thanks in advance for any advice/recommendations

    hawaii.ken

    Posts: 157
    Join date: 2012-01-31

    Re: ST 120 VTA driver board

    Post by hawaii.ken on Mon Mar 25, 2013 10:40 pm

    Like this?
    Custom build

    Maintarget

    Posts: 106
    Join date: 2013-02-10

    Re: ST 120 VTA driver board

    Post by Maintarget on Tue Mar 26, 2013 12:39 pm

    Ken,

    Beautiful work looks awesome, any updates, do you have any pictures under the hood for layout and wiring?
    I like the idea of replacing the ugly looking quad cap, any guidance on capacitor selection?
    My design will not have any visible fasteners anywhere everything will appear flush mounted, I plan on mounting the quad cap inside the inclosure, relocating the on/off switch to the front and the inputs to the rear, and designing a custom enclosure for the transformers other than that the unit will be as designed, so it's all cosmetic.
    Look forward to hearing from you and others on their specific custom builds.

    Maintarget

    Posts: 106
    Join date: 2013-02-10

    Re: ST 120 VTA driver board

    Post by Maintarget on Thu Mar 28, 2013 11:59 pm

    I figure with so many viewings and no responses either its a dumb question or nobody knows the answer.........
    I went ahead with my plan and am very pleased with the results, once I figure out how to post photos I will.

    Maintarget

    Posts: 106
    Join date: 2013-02-10

    Re: ST 120 VTA driver board

    Post by Maintarget on Fri Mar 29, 2013 12:42 pm

    Pictures of driver board ....






    hawaii.ken

    Posts: 157
    Join date: 2012-01-31

    Re: ST 120 VTA driver board

    Post by hawaii.ken on Fri Mar 29, 2013 2:10 pm

    Nice job!

    Are the ICs short enough to not get in the way?

    Bob Latino
    Admin

    Posts: 1821
    Join date: 2008-11-26
    Location: Massachusetts

    Re: ST 120 VTA driver board

    Post by Bob Latino on Fri Mar 29, 2013 2:21 pm

    If you are referring to the two LM334 IC's that regulate the current on the two phase splitters - then YES - each is lower than the level of the top of the three tube sockets ...

    Bob

    sKiZo

    Posts: 666
    Join date: 2013-04-01
    Location: Michigan USA

    Re: ST 120 VTA driver board

    Post by sKiZo on Wed Apr 03, 2013 10:36 pm

    Hmmmmm ... now would be as good a time as any to make that happen on mine ...


    Maintarget

    Posts: 106
    Join date: 2013-02-10

    Re: ST 120 VTA driver board

    Post by Maintarget on Sat Apr 06, 2013 1:47 pm

    I used clear 1" shrink tube mounted on cable tie mounting bases, instead of using zip ties around the Caps I notched the shrink tube underneath and threaded a straight piece of zip tie the length of the cap between the zip mount and the cap, then shrunk all together.
    The caps are now supported from the center as well as the leads and the information on the caps is clearly visible.

      Current date/time is Wed Apr 23, 2014 9:29 am