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    How to wire and how to NOT wire a VTA amp kit - photos ...

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    Bob Latino
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    Location: Massachusetts

    How to wire and how to NOT wire a VTA amp kit - photos ...

    Post by Bob Latino on Sun Feb 12, 2012 7:57 pm

    Below is what a VTA ST-120 wiring job should look like. This one was done by Sal Brisindi. Nice job, Sal .. If you want some quality work or repairs done on your tube amp send a PM through the forum here to member "Sal"



    Below is a wiring job that is IMHO the WORST wiring job I have ever seen on any amp built from a kit. No, it wasn't wired by a wino on New Year's Eve. I do know the "builder" but I will not publish his name here .. After he finished he sent me this photo and remarked to me > "It doesn't work? - Any idea what's wrong ?"



    Bob

    Sal

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    Re: How to wire and how to NOT wire a VTA amp kit - photos ...

    Post by Sal on Sun Feb 12, 2012 10:50 pm

    Thanks for the compliment Bob. I can't believe that messy wiring job, there is enough wire under that chassis to wire 5 tube amps...

    BTW, what was the problem with that amp? Must have been fun tracing all those wires. Did that amp pick up any radio stations with all that extra wire acting as an antenna.. Shocked

    Sal

    Bob Latino
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    Re: How to wire and how to NOT wire a VTA amp kit - photos ...

    Post by Bob Latino on Mon Feb 13, 2012 4:19 am

    A typical issue .... The amp kept blowing fuses ... The biggest problem here is that he did not "shorten the transformer wires to an appropriate length" as outlined in the assembly manual. Even though not shortening the wires might not make any difference in the sound of the amp, excessive wire WILL make a difference in your attempts to figure out why the amp doesn't work correctly. It's just a confusing mass of "spaghetti" in there and it is hard to tell what wire goes where?

    Bob

    baddog1946

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    Re: How to wire and how to NOT wire a VTA amp kit - photos ...

    Post by baddog1946 on Tue Feb 14, 2012 7:52 am

    Yikes!
    It must have been difficult to make such a mess as that. I do notice however that on the contact strip he used two smaller green caps instead of the larger yellow types and that is the only thing I can see that makes a little sense.
    Bob you have a sense of humor I like by publishing these crazy projects I recall the crusty amp and a few others.
    Sal: YOU ARE A MASTER!

    jhoak

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    Location: Central Florida

    Re: How to wire and how to NOT wire a VTA amp kit - photos ...

    Post by jhoak on Tue Feb 14, 2012 10:22 am

    You promised me Bob... Embarassed

    davidness

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    Re: How to wire and how to NOT wire a VTA amp kit - photos ...

    Post by davidness on Tue Feb 14, 2012 1:03 pm

    jhoak wrote:You promised me Bob... Embarassed

    Jeff! Don't tell me that was yours!

    Tube Nube

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    Re: How to wire and how to NOT wire a VTA amp kit - photos ...

    Post by Tube Nube on Tue Feb 14, 2012 1:13 pm

    Hey I didn't hear Bob naming names.

    On the positive side, there's no signs of fire or detonation damage. ;-)

    I think I would begin by cutting out all the wiring EXCEPT NOT the transformer wires. Probably want to reflow the solder in all the contact points on tube sockets and the circuit board. Then trim transformer wires as to Bob's excellent instruction booklet, and begin systematically re-wiring the job in as OCD a manner as I could muster.

    Actually, it'd probably be a fun "re-build" . . .

    Good luck.

    jhoak

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    Re: How to wire and how to NOT wire a VTA amp kit - photos ...

    Post by jhoak on Tue Feb 14, 2012 1:21 pm

    davidness wrote:
    jhoak wrote:You promised me Bob... Embarassed

    Jeff! Don't tell me that was yours!

    No it wasn't. Just trying to interject a bit of humor. Very Happy

    Guess I failed huh?

    Mine was not as "pretty" as Bob's work but not too bad either. Bob actually used my "under the hood" shot of the time delay board for a while. At least until he found a neater one.

    Captain Coconut

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    Re: How to wire and how to NOT wire a VTA amp kit - photos ...

    Post by Captain Coconut on Tue Feb 14, 2012 1:38 pm

    Bob Latino wrote:Bob

    I was going to award Sal's job as the tidiest, until I saw a stray bit of red wire between the left two output tube sockets. Now it's a tie! lol!

    Sal

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    Re: How to wire and how to NOT wire a VTA amp kit - photos ...

    Post by Sal on Tue Feb 14, 2012 2:56 pm

    Thanks,
    I just noticed another one between the line cord and on/off switch... damn.... now I have to take the picture over again.... sorry for being sloppy, I'll try to be neater next time Very Happy

    Sal

    Tube Nube

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    Re: How to wire and how to NOT wire a VTA amp kit - photos ...

    Post by Tube Nube on Tue Feb 14, 2012 3:02 pm

    ... and while we're nit picking, that transformery thing on the bottom left . . . is that a choke? Well, for Pete's sake, it's crooked! Throws the symetry of the whole thing off for me.

    ;-)

    Captain Coconut

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    Re: How to wire and how to NOT wire a VTA amp kit - photos ...

    Post by Captain Coconut on Tue Feb 14, 2012 3:13 pm

    This is like solving a puzzle - spotting Sal's miscues! Well, I think I have spotted another - if you look very closely at the bottom left corner, there appears to be miniscule piece of red wire, just below the brown wire loop.

    Boy, that spaghetti wired amp is looking better and better all the time! Suspect

    Sal

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    Re: How to wire and how to NOT wire a VTA amp kit - photos ...

    Post by Sal on Tue Feb 14, 2012 4:20 pm

    The mounting of the choke on the left is using the existing screw that holds down the left audio transformer so the choke is on a slight angle.

    You are correct Captain, now its 3 pieces of insulation I forgot to take out.. I feel so ashamed...

    Sal


    Last edited by Sal on Tue Feb 14, 2012 8:57 pm; edited 1 time in total

    Luddite

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    Re: How to wire and how to NOT wire a VTA amp kit - photos ...

    Post by Luddite on Tue Feb 14, 2012 4:36 pm

    Probably stray bits of stripped insulation rather than actual wire. The reason the choke is skewed is because of the mounting hole position which allows the choke to contact the side of the chassis (also notice there can be only one mounting screw). Understandable considering this is a modification (with dual chokes) using the original factory-standard chassis design.

    Best Regards,
    Charlie

    Tube Nube

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    Re: How to wire and how to NOT wire a VTA amp kit - photos ...

    Post by Tube Nube on Tue Feb 14, 2012 6:26 pm

    A hah! Then we all have chokes that are equally wonky at best, which in a way, restores symmetry!

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