83 tube UV output

[SteveH]

All,
Does anyone have a figure on the amount of UV that the 83 Rectifier tube puts out ? The reason I ask is my enclosure will be made of cherry - which upon harvesting is a light pink; but it turns that nice rich red color over the years...Due to UV light and oxidation. So...I don't want to have a blotch of darker area surrounding the 83 while the rest of the enclosure takes its 'natural' aging time.
If the numerical value is somewhat high, I think I will construct a nice brass 'reflector' that can stand behind the '83. Might look kinda neat anyway...

Thanks a bunch,
Steve

[mesherm]

The glass of the tube will block almost all of the UV-A and B so I doubt that you will have a problem. Now if the tube envelope was made of quartz....
I used some nice fine mesh stainless steel screen (80x80 mesh) for a heat shield on one of my amps. I have about 2/3 of a square foot left if you would like a piece 6" x 6'' or so I could mail it to you gratis. It would make a nice shield.

[erichayes]

Hi All,

I don't know what long term effect UVB radiation from an 83 will have on wood, but I have first-hand knowledge of the short term effect it has from a small Hg discharge lamp in a soda-lime silica envelope on a human retina. It can burn the Hell out of it.

If you want eye candy, a much better choice of tubes would be 0A2s or 0D3s. If you're using an 83 just for its pain-in-the-ass-to-use factor, don't leave it exposed to unsuspecting eyes.

[TomMcNally]

The devil made me do it - caution - I removed the UV filter from the camera !

[Shannon Parks]

Speaking of eye candy, what's the rule on gassy tubes? <insert jokes here>

One of my old 6B4Gs that I'm using right now is glowing a real nice blue on the upper 1/4 of the tube. I'm tempted to sort through the rest of my 6B4Gs to find one equally gassy. Transconductance tests fine, by the way.

[EWBrown]

The Sovtek / EH 300Bs put on a nice "light show", not only blue, but some weird green and purple as well, almost like small plasma globes ... The JJs only have a little blue. Then there are a couple of 60-plus year old brass base WE276As which flash over around 450VDC and then glow quite brightly. They're more gassy than a room full of guys at a chili-eating contest, this was a problem with some of the vintage brass base tubes, unfortunately. OF course, they're NG for any amp use.. Yellow_Light_Colorz_PDT_21

I know that Gary Kaufman uses 83s and 866 jrs on a couple of his amps, and hasn't had any issues with UV (and he's a MD, so he should know).

I had wondered about this several years ago, but the general consensus was that it was not a problem. You probably will get more UV out of a fluorescent light Yellow_Light_Colorz_PDT_11

/ed B in NH

[SteveH]

Thanks a lot for all of your help. Once I get back home and get my power transformer, Im going to take it back to one of my old Physics professors. He'll get a reading off of it for me, and I'll post the results....

Regards,
Steve

PS - Niffty pic there Tom :D

[TomMcNally]

The orange glow in my pic is from a pair of EH 300B's Ed ... they had a
strange dancing blue glow the other night for a few minutes when I first
turned it on, but it went away.

Just my 2 cents on the 83 rectifier ...
I built this amp over 2 years ago, with the intent of using a 5Z3, which is
pin compatible with the 83 ... then got the urge to try the 83. It works great,
no issues, no noise, yeah - it does need a time delay, but that's easy.

... tom

[EWBrown]

IIRC, a type 80 rectifier is also pin-compatible with am 83 and 5Z3. There is also a 2.5V filament version, the 82.

[EWBrown]

If the blue glow is only on the glass, it isn't gassy, if the "vacuum" glows colors, then it's gassy, and probably on the way off to tubular nirvana, like my flatulent WE276As Yellow_Light_Colorz_PDT_09

Speaking of retina damage, I have in my "archives" a UV "sterilizer" bulb / tube which will fit into a regular desk lamp fixture (highly NOT recommended to attempt this). I had ideas of making my own UV EPROM eraser, but thought better of this, and went and bought a small safe unit. Yellow_Light_Colorz_PDT_11 which will do up to 4 EPROMs at a time. That's leftover from back friom my Motorola Syntor and MCX-100 radio-hacking days. An 82S123 could hold 16 channels, a 2716 or 2732 could hold hundreds... Made lots of government surplus radios into very useful and nice 144 MHz ham rigs and radios for local vollie Firefighters and local cops, once I "broke" their metamagical PLL programming code Yellow_Light_Colorz_PDT_09

/ed B in NH