Oregon Electronics D6 HV supplies: info needed please

[Brian Beck]

Can anyone help me with documentation for these Oregon Electronic HV supplies, model D6? I could use at least the schematics and specs.

I saved these two beasts from the trash bin many years ago when my first employer was about to toss them out. They have rested in peace in my garage for 25 years awaiting my attention. I have no documentation, and web searches have brought me nothing useful. This company seems to have vaporized. I wonder if it might have been a spin-out by Tektronix employees. Both units are the same model although the front panels are different colors. One unit has a date code of 1956 on a choke.

Each unit has two separate HV regulated outputs, each adjustable from 0 to +600VDC. The raw +650VDC supply is brought out front too. These two outputs can be used separately or in parallel. There is an adjustable negative bias supply, 0 to -150VDC. A heater supply of 12.6VAC CT at 10A is available on the front terminals too. Meters indicate up to 600V, and 500mA. Tube complement includes six 807, one 6X5GT, two OD3, two 5R4WGY.

They would make useful bench supplies for any tube project up to and including large power amplifiers.

Does anyone know anything about these? Thanks in advance.

[Brian Beck]

Inside view, dusty and rusty, but dig that six-pack of 807s:

[Brian Beck]

And finally, the bottom view, nice and neat:

[DigitalJunkie]

It looks kind of Tek-ish to me. The layout,and the numbering on the bottom of the transformer are Tektronix type stuff.

Being an Oregonian i'd like to figure out the story myself.

[wa4htz]

Brian,

At the risk of stating the obvious, draw your own schematic. This actually isn't as hard as it sounds; it is just a little tedious and takes awhile. You have already stated quite a bit of information about the supplies and you know all of the tube types. Start with the tubes. From reading many of your posts in the tube forum (I read alot and talk little.) I suspect you have a tube manual or two. If not, all of the tubes you listed are pretty common and you can find the data sheets on the 'net, probably on Frank's tube pages. Also, you can do a 'net search for something like "high voltage variable power supply" and come up with schematics for several supplies. I did this some time ago and came up with the schematics for 2 or 3 Heathkits and a few other makes. It was suprising just how similar all the circuits were.

As I started to say, start with the tubes. Work back to the transformer from the 5R4s and the 6X5 (plates). Then work out from them (6X5 cathode, 5R4 filaments) to the rest of the circuit. You'll probably get to the 807s pretty quickly. I'm guessing that yellow wire is filaments, red is B+ (maybe only AC from the transformer), black is ground. Can't guess about the other colors. You will probably have to cut some of that beautiful lacing to trace all of the wires. You may also have to re-draw your schematic several times before it looks good; I know I have to when I try to draw a schematic from a piece of equipment.

And, yes, I think you're right; these look like they would make dandy variable bench supplies for tube experimenting. You'll find out how high the voltage goes when you finish refurbishing them and as to the max current - looking at that 6-pack of 807s, I'd say, uh, "healthy".

Good luck and keep us posted.

[Brian Beck]

At the risk of stating the obvious, draw your own schematic.

I surely will if I have to, but I was hoping for a miracle before I started down that path - that someone has the schematics, just waiting for my request! I know - it's pretty unlikely. Having suffered through "reverse engineering" a few times in the past, I'm trying to avoid it if I can. The basic functions of the tubes are pretty obvious, but wiring details often matter when trying to get something really old like this up and running again. Like you, I too loath cutting apart those nicely laced wire bundles.

Thanks for your comments, WA4HTZ .

[pmillett]

Also being an (ex) Oregonian...

I believe "Oregon Electronics" was the original name for Oeco (www.oeco.com), which still exists. They likely were a spinoff of Tek around or just after WWII. They are still building power supplies.

About 18 years ago I had them design a custom power supply for an industrial computer project...

At the time I believe they still maintained records going back forever... it might be worth an email to them; if you spark somebody's interest they probably still have the original documentation in a file somewhere.

Pete

[Brian Beck]

Great tip. Thanks Pete. I figured they were long gone, but OECO's website talks about their beginnings in the 40's, so it may well be them. I will contact them.