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    ST-70 driver board cover installation shortcut

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    fmorelli

    Posts : 20
    Join date : 2013-08-27

    ST-70 driver board cover installation shortcut Empty ST-70 driver board cover installation shortcut

    Post by fmorelli on Thu Dec 27, 2018 9:06 pm

    This evening I installed the driver board cover, which came with very thorough instructions. I found that I was able to easily install the board without having to actually remove it. I wanted to pass along a few points on how to do this, for those that are installing this on an already finished amplifier.


    • First of all I removed the tubes, the bottom cabinet (4 screws), and then hung the front half of the amp off the table so I could reach the board. The amp stays in place since the heavy transformers are on the back half of the amp, which remains on the table.
    • Unscrewed the four screws that hold the board. There is a locking nut underneath. For each screw, there are also two nuts (which act as standoffs) in between the board and chassis. Press on the board with one hand so that the two middle screws are sandwiched between the board and chassis. Carefully unscrew and remove the screw. Repeat this for the remaining 3 screws.
    • If any of the nuts moved around, use a couple toothpicks to line them back up and center the holes in the chassis and board.
    • Set the cover on the board.
    • Press up on the board to keep pressure on the nuts. Make sure they are lined up with the screw holes.
    • Start each of the 4 screws, and run them at least through the two nuts.
    • Make whatever adjustments to the cover which lines up. The most important line-up is that one can reach the bias adjusters. Tighten the four screws so they lock the top cover in place.
    • Flip the chassis around now, so you can see the board. I stood the chassis on its side.
    • I took a 9/32" 1/4" drive socket and put a small magnet inside. Run the remaining four capture nuts on the posts. You're done!


    Filippo
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    StevieRay

    Posts : 43
    Join date : 2009-01-09
    Age : 56
    Location : Central VA

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    Post by StevieRay on Mon Jan 21, 2019 9:08 am

    Thanks for the installation shortcut, but I'm sure I'll be too fumble-fingered / impatient to do it with taking lots of stuff apart.

    I ordered one and it should be here today.

    Question -- without screwing down, could the cover just lay on top of the screws, sliding down over caps and tubes?

    I won't be turning it upside down, the shelf doesn't shake, no cats to scratch at it or dogs to paw at it, no kids to pull up the cover and get introduced to 300+ volts etc.?  I guess people would say 'well what's the reason for it?'  But I like the look and it would still act as a dust cover.
    solderblob
    solderblob

    Posts : 55
    Join date : 2018-05-20
    Age : 73
    Location : Placerville, California

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    Post by solderblob on Mon Jan 21, 2019 10:23 am

    How about gluing four small (1/4") disc magnets to the cover.  Use some medium or thick CA glue.

    Dave
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    StevieRay

    Posts : 43
    Join date : 2009-01-09
    Age : 56
    Location : Central VA

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    Post by StevieRay on Mon Jan 21, 2019 11:05 am

    The chassis and screws are Stainless I believe, but I don't know what 'type' of stainless -- this is one of Bob's kits that's advertised to have a non-magnetic SS chassis.

    Hmmmmm.......
    Bob Latino
    Bob Latino
    Admin

    Posts : 2760
    Join date : 2008-11-26
    Location : Massachusetts

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    Post by Bob Latino on Mon Jan 21, 2019 11:07 am

    A magnet will not stick to any of the VTA stainless steel amp chassis ..

    Bob
    solderblob
    solderblob

    Posts : 55
    Join date : 2018-05-20
    Age : 73
    Location : Placerville, California

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    Post by solderblob on Mon Jan 21, 2019 12:44 pm

    StevieRay wrote:The chassis and screws are Stainless I believe, but I don't know what 'type' of stainless -- this is one of Bob's kits that's advertised to have a non-magnetic SS chassis.

    Hmmmmm.......

    Dang!  First idea I've had in 10 years...down the toilet!

    Dave
    Dave_in_Va
    Dave_in_Va

    Posts : 294
    Join date : 2013-04-02

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    Post by Dave_in_Va on Mon Jan 21, 2019 1:10 pm

    1/4" velcro "dots"?
    Peter W.
    Peter W.

    Posts : 1302
    Join date : 2016-08-07
    Location : Melrose Park, PA

    ST-70 driver board cover installation shortcut Empty Re: ST-70 driver board cover installation shortcut

    Post by Peter W. on Mon Jan 21, 2019 1:38 pm


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    ST-70 driver board cover installation shortcut Empty Re: ST-70 driver board cover installation shortcut

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