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.
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.
An externally hosted image should be here but it was not working when we last tested it.
Inside view
Inside view, dusty and rusty, but dig that six-pack of 807s:
Inside view, dusty and rusty, but dig that six-pack of 807s:
An externally hosted image should be here but it was not working when we last tested it.
Bottom view
And finally, the bottom view, nice and neat:
And finally, the bottom view, nice and neat:
An externally hosted image should be here but it was not working when we last tested it.
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.😉
Being an Oregonian i'd like to figure out the story myself.😉
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.
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.
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 .
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
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
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.
Sorry, I never saw a notification of your post. I just happened to come across this old thread again today. To answer your question, no, I never did get the schematics. I rebuilt one unit by replacing all the caps and checking all the tubes. It works just fine now.
If it hadn’t worked after replacing those parts, I might have needed the schematics. I got lucky.
Do you have one of these?
If it hadn’t worked after replacing those parts, I might have needed the schematics. I got lucky.
Do you have one of these?
Thanks, Brian - yes, I got one off of Ebay. Looks OK, except the meter faces are very rough, can't read them at all. I heard something about using compound for them, like is used on headlights. Anyway, the rest of it needs cleaning, but the chassis underside is clean - awesome workmanship in it. I'll do like you did, check the tubes and the caps. I can try to find a similar schematic from another Oregon supply to get a feel for what's doing what.
Use ultrafine wet and dry sandpaper on the plastic.
Sand wet in one direction only and use a plastic polish /paint polish or even toothpaste in a pinch.
Don’t circle the sanding as it takes longer to cut down
You buff “across” the grain of the sanding direction for quicker results.
They do sell a buffing pad and compound for headlight restoration you can use as well.
Regards
David
Sand wet in one direction only and use a plastic polish /paint polish or even toothpaste in a pinch.
Don’t circle the sanding as it takes longer to cut down
You buff “across” the grain of the sanding direction for quicker results.
They do sell a buffing pad and compound for headlight restoration you can use as well.
Regards
David
Adding to the good advice from David: On YouTube (so you just know that it has to be true) I watched a few videos on headlight cover restoration, which is essentially the same problem as you face. Once you've removed the haze with light sanding and buffing, you can apply a coat of gloss clear spray. You will need to remove any rubbing compounds first with alcohol wipes. Apparently the clear coat fills in the tiny scratches from the polishing and gives a "like new" appearance. I have not tried this, so you might want to try a tiny section first to see if it works well before spraying the whole thing.
Keep us posted on your progress.
Keep us posted on your progress.
Clear coat will work but getting back to the original surface will look better since you will have eliminated orange peel just by the buffing process.
Thanks, David and Brian - I'll keep you posted on my progress, which might be a little slow owing to the intrusion of my day job 🙂
I have one of these as well. It’s always worked fine.
I worked for Tektronix 37 years, I believe I got it there.
Pretty handy bench supply for us tube geeks.
Ron
I worked for Tektronix 37 years, I believe I got it there.
Pretty handy bench supply for us tube geeks.
Ron
Yes, VERY handy indeed! It has an unusual combination of high voltage and current capabilities, plus heater and negative grid bias supplies.
Bump, just scored one of these (Model D6) from a storage locker sale in Carson City and would love to have the schematic. I'm mostly designing tube preamps right now so it's honestly a little overkill, but I imagine I'll be grateful to have 600 Volts and half an Amp of headroom somewhere down the line!
The condition is variable as it's missing the walls, but hey, I got a deal on it, and restoring it will be a great learning experience, albeit a very very careful one. Transformers, tubes, chassy in excellent condition. Assuming the large black cylinders are inductive coils, they seem fine as well. Wiring is full of splits and cracks and all needs replacing, which is a damn shame because it was a very neat, well laid out professional factory job without any ******** mods. At least I have a great template for doing the rewiring well, and it's fairly easy to see how things are connected in case I'll need to draw the schematic myself. Haven't tested resistors yet but will probably replace all as a matter of course & to gain the experience. Capacitors to be replaced of course, though it's worth noting that, while the unit is pretty roughed up, it doesn't seem to have had excessive use as there are no noticeably leaky or bulging caps, and all the tubes test well. Seems like there's a light patch of rust on most terminals/connections so I might have to replace some of the tube sockets etc, but I'm hoping a quality re-solder job and/or dremel buffing can clean up most of those as it seems to be surface level at most. I am all ears for any suggestions/advice in this pursuit!
Oeco is a dead end, unfortunately - several employees confirmed the original name was Osborne Electronics when they started out in the 50's, and they changed to Oeco in 1961. Back to the drawing board! Would love to know the background on this classy unit for posterity!
The condition is variable as it's missing the walls, but hey, I got a deal on it, and restoring it will be a great learning experience, albeit a very very careful one. Transformers, tubes, chassy in excellent condition. Assuming the large black cylinders are inductive coils, they seem fine as well. Wiring is full of splits and cracks and all needs replacing, which is a damn shame because it was a very neat, well laid out professional factory job without any ******** mods. At least I have a great template for doing the rewiring well, and it's fairly easy to see how things are connected in case I'll need to draw the schematic myself. Haven't tested resistors yet but will probably replace all as a matter of course & to gain the experience. Capacitors to be replaced of course, though it's worth noting that, while the unit is pretty roughed up, it doesn't seem to have had excessive use as there are no noticeably leaky or bulging caps, and all the tubes test well. Seems like there's a light patch of rust on most terminals/connections so I might have to replace some of the tube sockets etc, but I'm hoping a quality re-solder job and/or dremel buffing can clean up most of those as it seems to be surface level at most. I am all ears for any suggestions/advice in this pursuit!
Oeco is a dead end, unfortunately - several employees confirmed the original name was Osborne Electronics when they started out in the 50's, and they changed to Oeco in 1961. Back to the drawing board! Would love to know the background on this classy unit for posterity!