Big, Heavy, Tube regulated Lambda Power supply

[E.Maxwell]

Whilst scouring the dumpsters at school today (near the dumpsters, actually ) I found a tube-regulated Lambda Model 50 p.s. It has a 0-500VDC output @500ma, two 6.3vac @ 5 amps each, and a bias output. It weighs about a billion tons (slight exaggeration), it has a voltage meter and a current meter on the front, it's made out of really thick steel, it has all it's tubes, and it looks like it's been sitting in someone's closet for the past 50 or 60 years. I had brief thoughts of plugging it in, but the power cord looks a bit sketchy. I tried to find some info online but couldn't. I'm not quite sure what to do with it, any suggestions? It has some massive transformers, all of which look to be in perfect condition, with no rust. Also, if anyone has more info on it, that would be appreciated. If anyone wants to see pics, I'll try to scrounge up a digital camera and post some.

 

[SHiFTY]

Score!

If it can provide 500V @ 500mA this will pretty much power any tube project out there, with the exception of transmitter tubes.

I wouldn't power it up until you check the condition of all tubes and caps.

Pics please!!

 

[EC8010]

You lucky thing! If it's been outside for a while, damp may have got to the transformers, so I'd leave it in a warm room while you think about what to do next. Bear in mind it's not only high voltage, but has quite a bit of current behind it. Thus, it could not only electrocute you, it could also start a fire. At the very least it will want the mains lead replacing and you will need to pay very careful attention to the earth bond down to the chassis. If I were you, I would test every single capacitor for leakage, particularly the big ones.

We really need photographs...

 

[highbias]

I have an Eico bench type HV supply that goes 0 to 450 volts at 375 mils plus the normal compliment of filament voltages and a variable 1 to 150 volt bias output. Its been handy and is going to come in handy again when I get those tube line stage pcb's from Hong Kong. In the past I've been using it to re-form electrolytics in vintage TV sets that I like to restore in my spare time(what little spare time I have). The set below is a 1946 RCA 630TS that is up and running again with all the original multi section electrolytic caps except for one stubborn one that would not re-form. All other coupling and bypass caps as well as all off value resistors and several mica caps that drifted in value have been replaced. The set contains 32 vacuum tubes... 4 video IF stages and three audio IF stages and true video DC restoration makes this one hot set and I was able to pull in the studio quality picture on the set with just a couple of clip leads attached to the antenna terminals in my basement shop. Far as I can tell it also has the original CRT! Isn't old tube stuff great.......

Mark

 

[EC8010]

Wonderful TV. Here's a photograph of the original BBC1 symbol. The rotating world was a 2" hollow frosted glass sphere with the "sea" painted on in black paint. A lightbulb was stuck inside, and bits of Meccano and a synchronous motor rotated it. Behind the globe was a curved polished stainless steel mirror. The "South" logo could be switched on an off electronically (!) by switching the fluorescent on and off. The whole thing was mounted in a Dexion frame and a Link 109 monochrome camera looked at it, then sent the (monochrome) signal to a colour synthesiser which switched in yellow for the white land masses and blue for the black sea. Wonderfully crude.

 

[SY]

Mark, does the U still have those wonderful surplus sheds? Back when I lived there, they were true Aladdin's caves.

 

[Circlotron]

Here's a photograph of the original BBC1 symbol. The rotating world *snip*

Did it rotate in the right direction? My favourite thing to spot in movies.

 

[EC8010]

Did it rotate in the right direction? My favourite thing to spot in movies.

Oh, Lord! I never really noticed. Ah!!! I know the way out of the quandary. THE WORLD IS FLAT. That solves the problem. (Oh, and the moon landings didn't happen either.)

Is E.Maxwell going to bring some photographs so that we can lust over his power supply?

 

[highbias]

"Mark, does the U still have those wonderful surplus sheds? Back when I lived there, they were true Aladdin's caves."

Ya know, I don't know about that.... I know others that have bought from there but I don't know if they exist any longer. O can try to find out though.

The U generally has quite a bit of surplus as they have a habbit of upgrading major things every ten years. Some of it may now go to the local chain of D.I. stores......

BTW: I love that BBC logo!!

Mark