Help me find some odd looking rectifiers!

[Fuling]

Hi,

I´m collecting parts for an "just for the looks"-amp with RCA 808 power tubes and DET20 (2C22) inputs.
Both of the tubes mentioned above has two topcaps each, so what I´m looking for is a rectifier tube that will mix well visually with these, ie 40´s style with one or preferably two topcaps.
Single diodes would be just as good as duals.

Each channel will consume 120-150mA @ 350-400VB+

Pictures of 2C22 and 808 to get an idea of what I´m looking for:

http://www.wiwitubes.com/pic/tube/RCA808.jpg

http://www.r-type.org/exhib/aai0283.htm

[Gluca]

I'd say EIMAC RX21 ... but they are hard to find. Or ... well ... globe 866As look gorgeous.

Ciao
Gianluca

[Steven-H]

I second the globe 866's. Simple looking but very pleasing.
Where did you find 808s ???????

[astouffer]

RCA has some mercury rectifiers smaller than the 866, the 816 I think. How about a bridge using selenium stacks? The larger ones are rather impressive with all the finned plates.

[Fuling]

Hi,

That Eimac rectifier looks good and so does 866 and 816 but
(I should have mentioned this in the first post) I´ll avoid mercury and gas filled rectifiers as they have to warm up before any HT can be applied. There are of course ways to deal with that, but I´d like to keep things as simple as possible.

I have four 808´s (2 JAN), all untested. I´ll have to test them to see if I got at least one functional pair before I invest any more money into this project.
Got the first 808 almost for free, the others has been hunted down over a period of about two years.
Quite rare and expensive tubes, especially in this corner of the world and there seem to be no subs.
I´ll build the amp so that they can be replaced with 811A´s with minor modifications.

BTW: Selenium rectifiers...well, worth a look! But aren´t they a mess to work with? (Toxic)

[liberty]

What do you think about this?

http://www.tektron-italia.com/images/RGN1404-TFK.jpg

[Colt45]

bah, don't bother with selenium

[Gluca]

(I should have mentioned this in the first post) I´ll avoid mercury and gas filled rectifiers as they have to warm up before any HT can be applie

You just need a switch to turn the B+ 20 secs after the fils (when tubes are lit up often), pretty easy and they sound better.

Ciao

[Fuling]

http://www.tektron-italia.com/images/RGN1404-TFK.jpg

Sweet looking rectifier for sure, but too old (and probably made of Unobtanium and very expensive)

bah, don't bother with selenium

That´s what my gut feeling tells me, too. Replacing broken selenium rectifiers with silicon diodes seems to be one of the more common repairments in old tube stuff.

Well, if I don´t find any good looking, cheap and easily obtainable tube rectifiers I´ll just use some damper- or sand diodes.
A cool looking tube rectifier would be nice but not necessary.
There will be some sand (mosfets) involved in the driver stage anyway, since the 808 needs positive bias and quite a bit of grid current to work in SE circuits.

[liberty]

Originally posted by Fuling

Sweet looking rectifier for sure, but too old (and probably made of Unobtanium and very expensive)

Yes, expensive. 70 Euro each.


http://www.tektron-italia.com/tubes/radios.shtml


maybe you can find something cheeper here:

http://www.benedettimauro.com/oldradio/valvolerare.asp