VVR3 - Hall Amplification -where can I buy a kitor PCB

[bluesfendermanblues]

Already bought 3 pcs VVR kit from Dana, installed in a 5e3 and to be installed in respectively a 18w clone and a EH185 clone. All cathode biased amps. All good.

However, for a 5f4 clone I need a VVR3 - where can I get a kit or a PCB and sourcing the parts myself.

Hallamplification.com is not working any more - Any clues?


What happened to Dana?

[xtian]

I've been building my own cathode bias versions on tag strips. Super easy. Are you looking for the fixed-bias kits? I guess you could go with London Power.

[John_P_WI]

London Power kits are great and are very transparent. The latest kits have moved on from a simple pass regulator, and if I recall, use a current mirror for "low control voltage" adjustment. This allows any sized pot to be used and simplifies the use of multiple pots for individual channel power scaling settings.

[bluesfendermanblues]

Thanks for the reply's

I prefer the simplicity of the VVR3 - the VVR in my 5e3 never made unwanted noise or heat. Totally reliable.

[Ron Worley]

IM Dana at UR12 on this board.

[Structo]

I sent Dana several emails wanting to purchase a VVR kit but I never got
a response.

[M Fowler]

Per Dana's FB he said the parts to build VVR's was very costly and was not sure if he is going to continue selling VVR's.

I guess a PM to Dana would be the best way to ask.

[sliberty]

I assume that what Dana meant is that the parts were too expensive for a business venture, and I can certainly see that. Especially with the support that you would inevitably end up providing (even if you tell everyone there is no support). But, if you build a VVR yourself, it is certainly wouldn't be very expensive, and it would be a very easy build. You might not get it to be as small as Dana did, but probably small enough.

[JazzGuitarGimp]

If someone can provide a schematic and BOM, I will do a pcb layout and make unstuffed boards available for purchase.

[sliberty]

We shouldn't be passing around Dana's schems unless he gives the go ahead. And, odds are, if he did that, he'd provide it himself

[John_P_WI]

In Dana's defense, I'm sure providing support to all of the problems that come along with uneducated installs, could be overwhelming to say the least.

[bluesfendermanblues]

Thanks for the inputs.

In reality the VVR3 is equal to the VVR only with additional bias tracker circuit. for fixed bias usage. I found a schemo on the interweb, which I believe is usable. guess all components can be fitted to a terminal strip.

I've pm'ed Dana, but got no reply. I have a DIY 5f4 Tweed Super craving a VVR3. So I'm gonna try using the schemo.

I understand people's concern for Dana, but it's the Mr. D story all over (plus on a minor scale Shad and Brown Note) . You cant get in contact with the man and you have to find alternatives. Hence, Fuchs etc.

BTW if someone need a complete VVR (without bias tracker) and alternative could be: http://www.tube-town.net/ttstore/Kits/P ... :5651.html

[dorrisant]

I've been asking around about this as well... I tried to contact Dana for a purchase without a response.

Does anyone have any clear pics of the board?

[xtian]

[img:590:288]http://www.guitarkitbuilder.com/img/VVR3.jpg[/img]

[katopan]

That power sliding circuit works but on the bias side, the mosfet actually doesn't buffer anything and works as effectively as just using the pot. I decided not to use it and that it could be done better.

Don't know if you're a member at Wattkins but we've been having similar discussions over there.
http://www.wattkins.com/node/24640

Big hint - Exactly the same as the B+ side but with a P channel mosfet, protection zener around the other way and no current measuring resistor (you don't need current limiting on the bias supply scaling) works a treat. This is what I suspected Dana's VVR was for years, although a recent re-look at the PCB photos and the component layout doesn't make as much sense for that, but looks more like it could be that power sliding circuit. I don't have a board so don't really know.