about 83 mercury rectifier

[Tfan69]

just a fast question about what to expect (visually) from an 83 rectifier
i found this pic googling around, now i'm building an aikido using the 83, but the blue glow is barely visible with lights off, and nothing anywhere near the below pic..
is just me that i'm expecting too much or it is right this way?

 

[analog_sa]

Sadly, life is not as glamourous as art. Or get a better camera/ use a tripod 🙂

 

[imfree707]

Rectifier Glow

Hey Guys, take a look at the magnificent glow of the rectifiers in this monumental 1955 vintage Philips 1000 watt amp playing Bach.

YouTube - Bach Toccta D-Moll on 1000W Audio Tube Amplifier EL6471

 

[SpreadSpectrum]

With a good camera, tubes often come out prettier in dark shots than they actually look in real life.

 

[77seriesIII]

imfree,

that ROCKS!!!

./e

 

[LAJ]

Ahh, mercury vapor rectifiers. I remember them from RCA TV transmitters. How much they glow is dependant on the current flow thru them. If they ever start turning green, its time to change them out or you will be off the air.

 

[Frank Berry]

And I remember Mercury Vapor rectifiers in AM transmitters too. You could watch the modulation in the brightness of the glow.
Just make sure the filaments are hot enough before you apply the high voltage!

 

[Tfan69]

Ahh, mercury vapor rectifiers. I remember them from RCA TV transmitters. How much they glow is dependant on the current flow thru them. If they ever start turning green, its time to change them out or you will be off the air.

yeah... didn't tought about current flow, the above video told me why i don't see the nice glow i was expecting, the tube is working at more or less 30mA, not enough to make the vapour glow

And I remember Mercury Vapor rectifiers in AM transmitters too. You could watch the modulation in the brightness of the glow.
Just make sure the filaments are hot enough before you apply the high voltage!

yes but.. i thought that preheating of the filaments was necessary just before turning on after long and probably side storage

 

[Frank Berry]

If the tube has been stored on it's side (even briefly), let the filament warm up for a minimum of 45 minutes before applying high voltage to the anode.
Otherwise, the arcback can be pretty dramatic and destructive.

 

[imfree707]

Danke Schoen!

imfree,

that ROCKS!!!

./e

Thanks for the kind words, 77seriesIII. The video clearly and dramatically showed what would have required me to compose a lengthy text on the subject of current-modulated glow in rectifier tubes. One can't beat the visual effect of Bach's toccata on those rectifiers!

 

[807tubenut]

I let my NOS 866's warm for 2 days when I first get a new set.

Arc over is a very real possibility with these type rectifier

 

[imfree707]

I Do Remember....

I let my NOS 866's warm for 2 days when I first get a new set.

Arc over is a very real possibility with these type rectifier

I've never used a mercury vapor rectifier, myself, but I remember a couple things from USAF Ground Radio Tech School in '74/'75. Application of plate voltage to an insufficiently heated mercury vapor rectifier results in catastrophic arcing and Air Force equipment that used those rectifiers usually had a thermal time-delay relay in the plate transformer keying circuit to prevent pre-mature power-up.

 

[807tubenut]

That's certainly one way to do it, I apply common sense, others fear the neglect, lest we forget this is antiquated stuff were dealing with here.


Vanilla just ain't my flavor.


And I am the Ice cream Man

 

[Miles Prower]

just a fast question about what to expect (visually) from an 83 rectifier
i found this pic googling around, now i'm building an aikido using the 83, but the blue glow is barely visible with lights off, and nothing anywhere near the below pic..
is just me that i'm expecting too much or it is right this way?

The Aikido is a small signal amp that doesn't pull very much current. You won't get much glow out of an 83 that way. More current, more glow from MV power diodes.