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

    Post by Bob Latino on Sun Feb 12, 2012 9:57 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 Mon Feb 13, 2012 12:50 am

    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 6:19 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 9:52 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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    Re: How to wire and how to NOT wire a VTA amp kit - photos ...

    Post by jhoak on Tue Feb 14, 2012 12:22 pm

    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 3:03 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 3:13 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 3:21 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 3:38 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 4:56 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 5:02 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 5:13 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 6:20 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 10:57 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 6:36 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 8:26 pm

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

    DynakitParts
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    Reminds me on a Past Dish

    Post by DynakitParts on Tue Feb 14, 2012 10:11 pm


    Nice work Sal...
    The "other" example reminds me of a pasta dish @ Mama Leone's.
    Just add some meatballs & a nice glass of Chianti.

    Mangiare my friend

    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 11:07 pm

    Say, didn't Mama Leone leave a note on the door?

    It said Sonny move out to the country!

    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 11:24 pm

    Thanks Kevin,
    What Bob neglected to say the spaghetti ST-120 was my first attempt, after to much wine.... Rolling Eyes

    Now where is my glass of wine.

    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 11:33 pm

    Nahhhh, I don't believe it's the same amp.

    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 Wed Feb 15, 2012 8:34 am



    The final outcome was that he purchased a new board and parts set and some new tube sockets from me. I instructed him to unsolder remove ALL the wiring from the point to which it was soldered. I gave him a new coil of hookup wire and told him to shorten all the transformer wires until they just reached their termination point. When you build these amps, you get a full color photo of what the wiring *should* look like. I told him to route the wires exactly as he sees on the photo and to take his time and double check the termination point of each wire. I never heard from him again so I assume that he got the amp together properly on the second try ..

    Bob

    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 Wed Feb 15, 2012 11:05 am

    . . . depriving you of (photographic) confirmation of the victory! Would have been nice to see the before and after!

    Good on you, Bob, for your 1st rate customer service -- here was a guy whose . . . loose interpretation of the instructions sure must have complicated the after-sales assistance.

    Say, maybe you could put those pictures up on your website as encouragement to hesitant builders. Picture it:

    [spagetti amp pictured here]

    "This could not happen if you follow our detailed instructions, however, if you do have problems, we'll be there with you to turn it into a solid, working amp"

    [picture Sal's amp as an example --once he cleans up those bits of wire insulation ;-0 ]

    Blitzen

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

    Post by Blitzen on Wed Feb 15, 2012 11:14 pm

    I almost hate to say this because it's so pretty, but...
    I actually have a beef with the wiring, Sal- when I learned amp building, I learned that the first thing you would wire up were the heaters, and they should be down in the corners of the chassis. This puts the AC wires in the most shielded position, and the other wiring can be easily moved away from it should there be any noise issue.
    Maybe it makes little or no difference in these particular amps, but you know we're always trying to do things ever better!
    Using solid wire really lets you bend and place them exactly the way you want; nice!

    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 Thu Feb 16, 2012 8:32 am

    As long as you TWIST AC heater wires, you won't get any noise issues with these amps. Twisting AC heater wires will insure that both wires of the pair are at right angles to each other at all times and the fields will cancel. Other general wiring paractices are that everytime you cross a twisted heater wire pair with another wire, try to do it at right angles to the twisted pair - don't run another wire right "beside" a twisted pair if you can help it.

    Bob

    baddog1946

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

    Post by baddog1946 on Thu Feb 16, 2012 9:18 am

    Hi Sal:
    Let me say that's one nicely wired amp kit you did there. I have gotten a few tips from it for the customized amps I am working on with aluminum chassis. In fact I printed a copy of it and have it on the wall at my bench as an example to inspire and remind me to take my time and do it right.
    The only thing I can see that could be done to it is to remove the extra pins on the octal bias sockets.
    I did this on a kit and it left a little more room and looked a bit tidier but you have succeeded in making a real gem there and I offer this humble suggestion with the respect you deserve here. Good work!

    p.s. What is the value of the single yellow cap you used in place of the piggy back version more commonly seen in the kit version?

    Tom

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

    Post by Tom on Thu Feb 16, 2012 10:02 am

    Casting my vote for "Thread of the Year"; and,

    Kinda glad I didn't post any of my build pics....

    Shocked Tom

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