VF14 Rejuvenation in U.K.?

[paulcheeba]

Hello, is there a tube mic expert in the U.K. who can regenerate a few tubes. Without sending through Brexit etc.
All the best
Paul

 

[paulcheeba]

Can someone even recommend a way to do it please?

 

[mjrippe]

Tube regeneration is dodgy at best, and fatal at worst. Attached is an article with some dubious claims.

 

[GeorgeToledo]

Regeneration of VF14 isn’t usually about baking them.

The idea of regeneration of a VF14 is based on the tube having been underheated in a U47. The tube is gradually brought up to the original operating values so that any deposits burn off the cathode. I’ve never done it but that’s the basis on which I’ve seen it discussed. Maybe that will help retrieve some of the old internet conversations about it.

 

[GeorgeToledo]

I see some overlap with what I’m describing in the section on cathode poisoning but I sure don’t think that’s the way I’ve heard of it being done with VF14. I think some people just try pushing the heater a bit past U47 spec but even still under the original operating spec.

 

[GeorgeToledo]

You might try cleaning the pins of the tube with some caig before getting into anything else, if it is that some sporadic discharge is happening. The contacts in a U47 may need cleaning as well.

 

[paulcheeba]

It’s weird I’ve been recommended it by 2 German’s called Andreas. I’ve had one done by Herr Grosser and it was still noisy but the signal ratio was improved,

 

[gyraf]

Paul,

Can I ask: Do you have a real u47/48 in desperate need for a VF14, or are you looking for turning worn-out tubes into a backup option?

/Jakob E.

 

[paulcheeba]

I have a couple of U47’s that would benefit from spares, I’m not a huge fan of the Fet or the glass variants. I’d love to get some more life out of these couple of vf14’s

 

[TLRT]

I use some vintage testers, I have a modded Neuberger RPM370 where I listen the tube noise thru a transformer balanced output thru the anode, or any other tube source. Never tried with VF14, but used the "cathode burning off" test with EF806s tubes successfully.

 

[paulcheeba]

I use some vintage testers, I have a modded Neuberger RPM370 where I listen the tube noise thru a transformer balanced output thru the anode, or any other tube source. Never tried with VF14, but used the "cathode burning off" test with EF806s tubes successfully.

Cool, where are you?

 

[TLRT]

Cool, where are you?

EU, Hungary

 

[TLRT]

I tried it,works well the neuberger can create heater max 200V, grids -100v and anodes up to 500v. Looks like I have only good vf14's they are not noisy.(sorry guys not selling)

 

[paulcheeba]

Did you read the title TLRT?

 

[lukas]

...maybe this guy can help http://www.pwl.mikrokontroler.pl/

 

[rogs]

...maybe this guy can help http://www.pwl.mikrokontroler.pl/

Same problem as with TLRT - the OP is looking for a UK based solution...

 

[TLRT]

Did you read the title TLRT?

I can arrange shipping without taxes,As my friends are coming often from London, but I just gave tips I dont have much experience. Maybe you can try the guys at Phaedrus Audio

 

[gyraf]

Phaedrus Audio - aren't they the guys that disguised a jfet and named it "super-ultra-tube" or something? I'd perhaps not set my expectations too high..

 

[Recording Engineer]

I’m not sure “disguised” is the right word, when they’ve always said that is exactly what they’re doing (from my understanding).

 

[kingkorg]

Phaedrus Audio - aren't they the guys that disguised a jfet and named it "super-ultra-tube" or something? I'd perhaps not set my expectations too high..

10$ worth of parts.