The Dynaco Tube Audio Forum

Dedicated to the restoration and preservation of all original Dynaco tube audio equipment - Customer support for Dynaco VTA tube amp kits, all Tubes4hifi.com products and all Dynakitparts.com products


    Just finished my first VTA Board build.......how's it looking?

    Share

    Doctor Hugocat

    Posts : 75
    Join date : 2015-08-19
    Location : Los Angeles CA

    Just finished my first VTA Board build.......how's it looking?

    Post by Doctor Hugocat on Fri Nov 20, 2015 2:01 am

    Well, I just finished my first little kit build: a VTA board for my St-70 project. I know it's simple stuff to the rest of you guys, but this was the first non-repair project I've done. It was good fun, and I only made one mistake (I think), easily de-soldered and rectified. Of course, I haven't actually powered it up yet....... Very Happy

    " />

    " />

    " />

    " />

    peterh

    Posts : 641
    Join date : 2012-12-25
    Location : gothenburg, sweden

    Re: Just finished my first VTA Board build.......how's it looking?

    Post by peterh on Fri Nov 20, 2015 2:39 am

    Looks nice!

    Doctor Hugocat

    Posts : 75
    Join date : 2015-08-19
    Location : Los Angeles CA

    Re: Just finished my first VTA Board build.......how's it looking?

    Post by Doctor Hugocat on Fri Nov 20, 2015 2:45 am

    Thanks PeterH! Laughing

    10-E-C

    Posts : 75
    Join date : 2014-02-12
    Age : 62
    Location : upper east tn

    Re: Just finished my first VTA Board build.......how's it looking?

    Post by 10-E-C on Fri Nov 20, 2015 5:53 am

    Very good job, you will like the performance of this upgrade. I built one for my ST-70 and was extremely satisfied with it.

    TM

    eickmewg

    Posts : 38
    Join date : 2014-08-29

    Re: Just finished my first VTA Board build.......how's it looking?

    Post by eickmewg on Fri Nov 20, 2015 6:51 am

    I like the symmetry of your resistor codes. Mine are quite haphazard. I'm sure that it confuses all those electrons that race around the board. Nice job.

    audiobill

    Posts : 271
    Join date : 2014-03-13
    Location : Philadelphia

    Re: Just finished my first VTA Board build.......how's it looking?

    Post by audiobill on Fri Nov 20, 2015 9:10 am

    Very nice!

    PeterCapo

    Posts : 380
    Join date : 2008-12-05

    Re: Just finished my first VTA Board build.......how's it looking?

    Post by PeterCapo on Fri Nov 20, 2015 11:41 am

    Nice work.

    Bob Latino
    Admin

    Posts : 2374
    Join date : 2008-11-26
    Location : Massachusetts

    Re: Just finished my first VTA Board build.......how's it looking?

    Post by Bob Latino on Fri Nov 20, 2015 3:48 pm

    Good job ... You can tell some care went into building that board ..

    Bob

    sKiZo

    Posts : 1285
    Join date : 2013-04-01
    Location : Michigan USA

    Re: Just finished my first VTA Board build.......how's it looking?

    Post by sKiZo on Fri Nov 20, 2015 4:06 pm

    Very nice ... but ...

    (you just HAD to know there'd be some "but"head to ruin the day, eh.)

    I'd redo the socket tabs. Looks like you got good flow going through the holes to both sides, but incomplete coverage on some. If the solder's heated and pooled properly, all the tab surfaces will be covered, and there won't be any sharp edges or bulging to the solder. The solder on the legs themselves should look seamless with the metal. That works better if you heat the leg first, then slide the iron down to the pad on the board, as those can pop loose if you get them TOO hot ...

    Those sockets take a LOT of stress, especially if you're a tube roller like me. Heat cycles can also cause failure, so the better the joint now, the less chance of problems down the road.


    Doctor Hugocat

    Posts : 75
    Join date : 2015-08-19
    Location : Los Angeles CA

    Re: Just finished my first VTA Board build.......how's it looking?

    Post by Doctor Hugocat on Fri Nov 20, 2015 8:56 pm

    Thanks for all the encouragement everyone!! Much appreciated. This gives me a boost for the next part of the project, putting it all together...... Shocked

    sKIZo, I'll do as you suggest and re-solder those legs: as you say, better to double-check now than repair later.

    sKiZo

    Posts : 1285
    Join date : 2013-04-01
    Location : Michigan USA

    Re: Just finished my first VTA Board build.......how's it looking?

    Post by sKiZo on Fri Nov 20, 2015 10:36 pm

    Most problems are either bad or missing solder joints, so the attention to detail part can pay off with big dividends. Last step is to go through and do the the old tweak 'n twiddle test on all connections to make sure they're solid. Common sense, but easily overlooked if you're in a hurry.

    One thing to keep an eye out for is shorts to ground around the VTA board when you assemble the chassis. Real close tolerances, so you'll want to trim any excess leads close and make sure you don't pinch any wires ...

    PS ... the fun starts first time you plug it in. I've got a good 600 hours of fun on mine now ...

    nerpissad

    Posts : 58
    Join date : 2012-09-16
    Age : 43
    Location : amsterdam

    Re: Just finished my first VTA Board build.......how's it looking?

    Post by nerpissad on Sat Nov 21, 2015 8:37 am

    I can't see any of your photos?

    Maintarget

    Posts : 208
    Join date : 2013-02-10

    Re: Just finished my first VTA Board build.......how's it looking?

    Post by Maintarget on Sat Nov 21, 2015 2:30 pm

    Nice job the attention to detail up front in the assembly stage pays huge dividends down the road with over a 1000 hours on my ST-120 with only minor self inflected issues (Read & follow the detailed instructions) it has been trouble free.
    Those nice shinny cones on your solder joints is what you are looking for not too shallow and not to tall and as sKiZo has suggested clip those excess leads back to the tops of the cones.
    Once completed you are in for a treat as it will sound awesome and you can take pride in knowing you assembled it!
    Cant wait for some updates on your progress.

    deepee99

    Posts : 1260
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: Just finished my first VTA Board build.......how's it looking?

    Post by deepee99 on Sat Nov 21, 2015 5:47 pm

    Beautiful. Keep the pics coming. Skizo's caveats are worthwhile, of course. I had a bad solder joint on a bias trim pot lede, drove me nuts and it was impossible to see.

    Doctor Hugocat

    Posts : 75
    Join date : 2015-08-19
    Location : Los Angeles CA

    Re: Just finished my first VTA Board build.......how's it looking?

    Post by Doctor Hugocat on Sat Nov 21, 2015 7:53 pm

    Many thanks guys, the feedback is much appreciated and helps a lot to keep me encouraged with the project. Smile

    Thanks for the tip on clipping the soldered leads short: I'll go over the board once more and do that, at the same time I re-flow the socket tube contacts.

    Next job will be fitting the board and then the transformers: I'm following the original Dynaco manual for order of assembly.

    arledgsc

    Posts : 330
    Join date : 2012-11-30
    Location : SF Bay CA

    Re: Just finished my first VTA Board build.......how's it looking?

    Post by arledgsc on Sun Nov 22, 2015 11:50 am

    Excellent job!  You are off to a great start. What did you use to clean up the solder flux?

    Doctor Hugocat

    Posts : 75
    Join date : 2015-08-19
    Location : Los Angeles CA

    Re: Just finished my first VTA Board build.......how's it looking?

    Post by Doctor Hugocat on Sun Nov 22, 2015 2:52 pm

    Thanks Arledgsc! I used a contact washing solution made by DeOxit. We have one 'old-school' electronics store left in the northern part of Los Angeles and they stock it.

    Sponsored content

    Re: Just finished my first VTA Board build.......how's it looking?

    Post by Sponsored content Today at 9:55 pm


      Current date/time is Sun Sep 25, 2016 9:55 pm