Vox AC30 Breaking up Too Soon

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diagrammatiks
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Re: Vox AC30 Breaking up Too Soon

Post by diagrammatiks »

1n4007s are 1000volt piv diodes.

they have enough voltage.

2 or 3 makes things safer.
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ToneMerc
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Re: Vox AC30 Breaking up Too Soon

Post by ToneMerc »

The New Steve H wrote:
Now I have to figure out a sturdy way to put diodes in series.
Why go through the hassle, use one 3000V or 4000V diode. You can get these at Mouser for around .50 a pop.

http://www.rectron.com/data_sheets/r2500-r5000.pdf


Maybe it's time to pass the plates for a couple of Pro Reverbs

TM
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The New Steve H
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Re: Vox AC30 Breaking up Too Soon

Post by The New Steve H »

As noted in my last post, I have big diodes on the way. Tacking 1N4007s together with capacitors is too much aggravation.
Relax. It's SUPPOSED to smoke a little.
diagrammatiks
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Re: Vox AC30 Breaking up Too Soon

Post by diagrammatiks »

what diodes did you get?
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The New Steve H
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Re: Vox AC30 Breaking up Too Soon

Post by The New Steve H »

I looked at the Immortal Mod page and ordered what they suggested: STTH112U
Relax. It's SUPPOSED to smoke a little.
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ToneMerc
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Re: Vox AC30 Breaking up Too Soon

Post by ToneMerc »

The New Steve H wrote:I looked at the Immortal Mod page and ordered what they suggested: STTH112U
Did know that the "U" is surface mount and not the DO-41 axial package?


http://www.datasheetcatalog.org/datashe ... s/9343.pdf
diagrammatiks
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Re: Vox AC30 Breaking up Too Soon

Post by diagrammatiks »

IF(AV) 1 A
VRRM 1200 V
Tj (max) 175 °C
VF (max) 1.65

that's almost the same ratings as a 1n4007..other then being fast recovery of course.

Then again...I read your posts and it seems like you were just trying to protect a valve rec...so you didn't really need to put those in series anyway?

the stt's will work...

surface mount packing might be a problem.
tubeswell
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Re: Vox AC30 Breaking up Too Soon

Post by tubeswell »

diagrammatiks wrote:the stt's will work...

surface mount packing might be a problem.
Yes - might mean ordering more parts (like mica washer/spacers and insulated nylon bushings/grommets for the mounting bolts) if they're going to be chassis mounted. be interested to see whether this works out cheaper/less-bothersome than 4 x 1N4007, 4 x .01uF 3kV caps and a tag strip.
He who dies with the most tubes... wins
diagrammatiks
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Re: Vox AC30 Breaking up Too Soon

Post by diagrammatiks »

tubeswell wrote:
diagrammatiks wrote:the stt's will work...

surface mount packing might be a problem.
Yes - might mean ordering more parts (like mica washer/spacers and insulated nylon bushings/grommets for the mounting bolts) if they're going to be chassis mounted. be interested to see whether this works out cheaper/less-bothersome than 4 x 1N4007, 4 x .01uF 3kV caps and a tag strip.
might be but they are supposed to be soldered on top of pads that have a lot of surface area comparatively.

If you are looking for something easier...the prices of to-022 package diodes are really low now.

they are pretty easy to do on a little bit of vero or even turret if you get them close enough together.
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The New Steve H
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Re: Vox AC30 Breaking up Too Soon

Post by The New Steve H »

I thought it was extremely weird to specify diodes in that shape, but I assumed whoever picked them wasn't a total idiot. Maybe this was optimistic.
Relax. It's SUPPOSED to smoke a little.
Zippy
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Re: Vox AC30 Breaking up Too Soon

Post by Zippy »

The New Steve H wrote:When the bass player plugged the amp in, the light came on. Then he turned it on, and the light went off. At home, it works fine.
How does an ON/OFF switch change function dependent on the wiring of the wall socket? I still gotta hear more about that.
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The New Steve H
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Re: Vox AC30 Breaking up Too Soon

Post by The New Steve H »

Well, the diodes arrived. I knew the shape was not ideal, but I had no idea they were the size of BBs. I don't know if there is a prize for dumb parts buys at Amp Garage, but I am submitting my entry.

I should add that I used a socket tester on the outlets at church, and I found nothing abnormal. Which is amazing, considering how they do things there.
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Zippy
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Re: Vox AC30 Breaking up Too Soon

Post by Zippy »

Might you have just flipped the switch orientation during some hasty rework?
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The New Steve H
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Re: Vox AC30 Breaking up Too Soon

Post by The New Steve H »

I haven't messed with the switch. The light works fine here at home.
Relax. It's SUPPOSED to smoke a little.
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