Servicing a VOX Super Beatle V1142 this weekend.

[SoulFetish]

R.G.'s new power switch pc board is lot more elegant than the rat's nest of wires that has been added here.

I’ll be sure to pass on the kind words

[52 Bill]

I’ll be sure to pass on the kind words

Sorry, I didn't mean to offend you or him. I'll not comment anymore.

[R.G.]

There is a photo essay on how to repair that broken switch wafer at thomas-vox-repair.com in the tips and resources page. Ignore the DIY PCB there. I'm busy revamping that right now, based on safety concerns. In spite of the fact that the Thomas Vox amps would not come close to passing a modern safety inspection. And to be fair to Bill, the wiring in the picture is a little more enthusiastic than tidy.

[drewl]

I have found newer more robust rotary switches for these amps in old style modem switchers typically available at thrift stores or pawn shops.

[R.G.]

I have found newer more robust rotary switches for these amps in old style modem switchers typically available at thrift stores or pawn shops.

Hey!! Great idea! What are the ratings printed on an example switch??

The work on Vox switches has uncovered a wealth of conflicting requirements. Replacement wafers are theoretically available, as they are still made. They are quite expensive, about $25 per wafer, and then you still get to rebuild the mechanical assembly - which is riveted, not screwed, together. Thomas switched the AC (2A) with the switch assembly as well as the speaker line (up to 12A in the Beatles) and indicator lights (31V at 40ma) with the same assembly. So in the same switch you have to cover low voltage/low current DC, low voltage/high current AC, and high voltage mains current.

I couldn't find affordable high current mains switches that were small enough to fit in the box while also having enough creepage and clearance distance between the contacts to isolate the mains switching from the secondary low current lights and secondary high current speaker contacts.

[drewl]

Not the best one, but I have a few of these laying around.

They are rated for 3A, so you could gang a few together for the speaker.
Pushing it for a Beatle, but for the lower powered amps it should be fine.

Crappy picture is due to sand in the phone camera lens from the beach.

[R.G.]

Very interesting. I'll have to go see if I can find one. Give that there are many wafers, you might get enough creepage and clearance distance by skipping a wafer or two and putting the line stuff all by itself. Switches in parallel don't exactly increase current capability because of them not making simultaneous contact, but it would sure be better than no switch.

How long is that thing from mounting surface to the back of the switch? And how many layers/decks?

[drewl]

ten wafers, 3" long.

These switches were in Gibson Medalist amps I believe, but I don't know the current rating.

[R.G.]

Three inches long would go in the space in the amps. Guess I better get myself to a Goodwill Computer Works store.

I checked ebay. They run about $18-$20 on ebay. That's about cost of parts for the replacement setup. The replacement needs
> rotary switch with 2.5A to 6A switch rating. These are about $9 (Mouser)
> speaker relay, about $5.25
> X2 rated cap, about $0.75 - $0.90
> misc parts, about $2-$3

Add a PCB, even home made, and you're about the same price as the used/ebay units, unless you get one really cheap.

[drewl]

I know I've seen the wafer switches like the originals in assorted test equipment over the years.

I'll try and make a list so if you see something being thrown out or for cheap somewhere.

[R.G.]

I'm trying something different. I will occasionally look in aliexpress for odd parts. Sometimes I find them, and sometimes when I order them, they actually arrive.
There is a lot of placing bets involved in life; at least these are known to be gambles.

I found rotary switches based on ceramic wafers, with what I ...think... are the right number of poles, positions, index angle, etc. to do this repair. These switches are based on the old fashioned wafer switch setup with long screws to build up the switches. The idea here is to (1) actually get the switches, (2) disassemble them (3) disassemble the original Vox switch for the AC power switch, (4) assemble the AC power section on the end of the ceramic wafer switch, (5) have a party.

What can I say? It's a gamble.

[Fretts]

I can't resist jumping in here -- I must be about the same age as RG because all the same things happened to me when Thomas Vox amps were new. I DID get to play most of them since I was in a popular band and a big minnow in a very small pond - my band got to borrow amps for the weekend now and then and we were in a Vox sponsored battle of the bands. Even though I was the lead player, I somehow got assigned a Royal Guardsman which has half the power of a Super Beatle. Consequently, I dimed it for the set and hit the Watchdog like gangbusters in my solos. It caught me off guard but I ran with it. Later, I got a ton of compliments and major questions from the other guitar players on what I was using to get that effect!
Then, ten years later when you couldn't even give away a Vox amp (Marshall, Marshall, Marshall), I got the bright idea to outfit our whole band with a "wall" of Super Beatles which we could pick up for nothing in the paper and pawn shops and yard sales. As the solder jockey in the group, I ended up being the guy to resurrect the corpses. I had to buy an extra-long phillips screwdriver to get the chassis out. Thomas was still in business and actually sent me schematics which I still have. I got very familiar with the differences between the V1141, V1142 and V1143 versions. I favored the '43s, they had FETs in strategic places including a P-Channel unit that cost ten times what an N-channel one did. I used to think that part of the rich sound was due to the use of interstage transformers but it was probably the FETs and the Watchdog in reality. Anyway, Vox has been a constant in my world ever since... I still have a tube Cambridge Reverb which sounds great. I never suffered a broken wafer switch in all that time, but a lot of FETs died and I kept a bag of those on hand for a long time.

[olddawg]

I remember buying complete, working Super Beatles for $80 (or less) in the early/mid 70s and canibalizing the speakers to make monitor wedges. The rest... head, frame, etc went in the dumpster. I remember putting 6 Silvertone 1484 chassis in a dumpster too. At the time, worthless.

[SoulFetish]

Well well well, if it isn’t Mr. lead dress himself.

Welcome To the forum Scotty!

[SoulFetish]

Hey, what the hell just happened? Where did he go?