VVR Install Problems

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Deric
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Re: VVR Install Problems

Post by Deric »

And w/o exception every time there always an excuse explaining how it wasn't an insult because it's always done in a way thats crafted as to be explainable if the occasion reqires it as in this instance.
Exactly! :D

You can explain how yours wasn't an insult ... and so can anyone else.

Just sayin'.
Deric®
tubetek
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Re: VVR Install Problems

Post by tubetek »

bnwitt wrote:We could all stand in a line and thank the guys on both sides. No Allyn Mey and no Asteroid layout. No Dana brother of Richie (another shameless sharer) and no VVR. No Richie (Brother of Dana) and no 18 watt. Thank you Dana. Thank you Allyn. Oh and yes, Thank you Richie, Kentucky and Mother of Dana and Richie. Sharing without reward is what has made the tube community so damned special since I can remember back to 66 when I smoked my first resistor. And no, it wasn't in a bong.
AMEN! (and ain't them resistors hard to keep lit?!) Damn, Barry, you must be as old as me!
Tom
Tubetwang
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Re: VVR Install Problems

Post by Tubetwang »

I think that Dana's VVR is selling WAY below what it should be selling...
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Structo
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Re: VVR Install Problems

Post by Structo »

Once again, intent and context have lead to hard feelings.

Forums are twitchy things, sometimes it's best to use the little smilie things at the left to show intent. :wink:

I read the whole thread and I can see the issues from both parties.

In the end, Dana has always been helpful and hopefully will continue to be so. :)

Johnny I can see your point as well but sometimes when you question somebodies work they get their feelings hurt which can lead to further turmoil.

I would suggest that if you feel the mosfet is not safe having the drain connected to the heatsink tab, that you should buy the one that has no connection to it. That would ease your mind about having the high voltage there. :wink:

Dana, although I have not used your circuit (yet :wink: ), I thank you and the others with brilliant minds that think up this stuff and continue to share with us solder junkies.
:D
Tom

Don't let that smoke out!
Tubetwang
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Re: VVR Install Problems

Post by Tubetwang »

Structo wrote:Once again, intent and context have lead to hard feelings.

Forums are twitchy things, sometimes it's best to use the little smilie things at the left to show intent. :wink:

I read the whole thread and I can see the issues from both parties.

In the end, Dana has always been helpful and hopefully will continue to be so. :)

Johnny I can see your point as well but sometimes when you question somebodies work they get their feelings hurt which can lead to further turmoil.

I would suggest that if you feel the mosfet is not safe having the drain connected to the heatsink tab, that you should buy the one that has no connection to it. That would ease your mind about having the high voltage there. :wink:

Dana, although I have not used your circuit (yet :wink: ), I thank you and the others with brilliant minds that think up this stuff and continue to share with us solder junkies.
:D

Took the words right out of my brain... :roll:
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jaysg
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Re: VVR Install Problems

Post by jaysg »

Structo wrote:I would suggest that if you feel the mosfet is not safe having the drain connected to the heatsink tab, that you should buy the one that has no connection to it.
Bob R uses those...~$22 at digikey and they use a clip system instead of a 4-40 through the body.

There was a long battle on some forum about the scaling pot being dangerous...that Rosk moron finally shut up when someone pointed out all the Fender amps with a chassis mount bias pot.
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bclick
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Re: VVR Install Problems

Post by bclick »

Wow, did this thread get crazy! Anyway, I always try to give thanks wherever it is due, and I am certainly thankful to Dana for helping me out, and everyone else that contributes. I made a bonehead mistake right off but Dana has been very patient.

Deric, do you mean twisting B+ In & Out wires together? My B+ In was very short - just a couple of inches from the diode soldered directly to the standby switch.

Another dilemma for me is where to mount the VVR pot. I already have the PPIMV in the 2nd speaker jack. I suppose it comes down to drilling another hole in the front or rear face plate. I was just trying to see if I liked it before drilling another hole.

-----------------------------------------------
Bil
Jana
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Re: VVR Install Problems

Post by Jana »

Wow, did this thread get crazy!
It's the planets, Pluto moved into Capricorn. All kinds of weird stuff happens.
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bclick
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Re: VVR Install Problems

Post by bclick »

+1 Tom (tubetek)!!! :lol: :lol: :lol:
drz400
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Re: VVR Install Problems

Post by drz400 »

iknowjohnny wrote:Whoa !!!! I had no idea the insulator was keeping B+ from ground ! In that case i wouldn't even consider using one of these unless i used a seperate heatsink that is not touching circuit ground. Maybe i'm over reacting, but no matter how reliable those insulators are, just the idea that it's all that seperates B+ from ground wouldn't allow me peace of mind no matter how convincing an argument i was given. If i were to use one i would now float a heatsink on a terminal strip or such and use that. tho it would be tough in a cramped amp.
If it shorts out you blow a fuse
You can use a ceramic heatsink insulator from Digikey that is .050" they work just fine if you dont want to trust the thin pads
drz400
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Re: VVR Install Problems

Post by drz400 »

UR12 wrote:[ Are you sure your name isn't Gary Moore :lol:
LOL!

There is nothing wrong with the voltages there or on any pot that is rated correctly. As Dana says there are plenty of places that high Voltage is close to ground, look at the standby switch or your power tubes ! What happens when a power tube arcs the socket? A well built amp will be protected as you will be. But you can use the thicker spacers which still act as a heat sink. There are amps with Power Scaling that are CE as well. Besides, 300VDC low current doesnt hurt that bad :wink:
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bclick
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VVR Install Problems

Post by bclick »

I installed a new mosfet and 2 new diodes with no real change. The volume reduces some below 50% on the VVR pot but does not sound good. The loud buzzing still happens between 40% & 60% on the VVR pot.

Power tube B+ and bias voltages are tracking up and down as before.

Is there anyone that has succesully installed this on a model 1987 Marsall 50 Plexi? Either Marshall or replica?

Here is a layout drawing to complement the schematic.

- Bil
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Richie
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Re: VVR Install Problems

Post by Richie »

Is there anyone that has succesully installed this on a model 1987 Marsall 50 Plexi? Either Marshall or replica?
I've installed the VVR in a few 50 watt marshalls, some fender bassmans,deluxes, a concorde type amp,and quite a few other amps. never had any problems.
In the marshalls, I mounted the board/mosfet on the end of the chassis,and the control on the front panel.
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bclick
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Re: VVR Install Problems

Post by bclick »

Hey Richie -

Would you please take a look at the layout I just posted, and the schematic & pics I posted on 11/26/08 and see if that is the way you wired your 50 W Marshall?

I currently have the mosfet bolted to the end of the chassis with a heatsink opposite. The VVR pot is suspended in the air on the 6 twisted wires. Temporary mount for evaluation.

I greatly appreciate any help.

- Bil
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Structo
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Re: VVR Install Problems

Post by Structo »

man, after reading the few threads here and over at the Power Scaling forum, a lot of guys have trouble installing these power scaling devices.

The difference between here and there, at least you don't have to buy $400 worth of books to install Dana's! :D

The TUT series of books is probably an excellent reference set and are probably good to own, but everytime somebody asks Kevin O'Connor a question he refers them to one of the TUT volumes. :roll:
Tom

Don't let that smoke out!
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