Help identifying / any ideas for this amp?

[gabe real]

those 2 big things on top look like cans of beans or something.
maybe with a lil pork.,
cranberry?

sorry for jokes.
looks cool
good luck

[sthslvrcnfsn]

The tubes are mostly RCA and Raytheon. There are one each of Sylvania and Westinghouse. Are these worth anything? How would they sound good in other audio units (think ART Pro VLA or cheap Presonus tube preamp)?

The unit that is missing out of the chassis is the one I pulled out to take pictures, so the chassis is actually full with all 7 units! Tonight I'm going to solder a plug on the end of the bare-wire power cord, plug it in and see if any of the units turn on. If they do I might try to pass audio through them.

Does anybody (or Doug hopefully) know if there are typical impedances or voltages/amperages associated with BNC connectors, if at all?

Update: I cleaned up all the units and the chassis today, and everything at least looks real nice...

-jim!

[emrr]

Dude! Are you trying to start a fire! Do you know what a variac is? If you don't then please step away! You will be very lucky if you don't cause a major malfunction by plugging these things in without a proper methodology.

There is no such thing as a typical anything in cases like this.

[sthslvrcnfsn]

Man alive Doug, relax! I didn't plug it in! Care to tell me what you're so hopped-up about? I mean, I'll take your word that it's dangerous and trust you on that, but freaking out doesn't do me much good unless you explain what the potential problem is.

By methodology, I hope you mean finding out the proper power requirements. I didn't type that out because I thought it would be obvious. I wouldn't go through plugging it in and testing it if I wasn't sure I was giving it the proper power. When I said I was "going to see if any of the units turn on", I was thinking that some of the edge connectors might be dirty or missing connectors; or maybe the cables were bum in a few spots or something. NOT that I was going to stick some wires in an outlet and hope for the best.

I've been electrocuted by 120V and 220V enough times (low amps every time, thank god) to know that I should always treat electricity with a lot of respect. I was dumb when I was a young chap - plugging stuff in wrong, fiddling around with screwdrivers inside things, rewiring stuff without any regard for schematics and circuits. It was sort of neat, but actually not very much fun in the end because I got zapped so many times. Maybe that's what's wrong with me these days, haha.

I mean does this thing most likely run on 220V? Or is the amperage high enough to cause an arc when I'm going to plug it in?

Sorry to scare you man! But please let me know how you would go about doing this. You seem to be so wise in the ways of repairing old gear that I would like to hear what you have to say.

-jim!

[emrr]

By methodology I mean 'how to apply power to old gear that's not been used in 30 years'.

First off, these don't have a power supply. They need an external high voltage and filament supply to work.

Next, I mean old electrolytic capacitors that have been sitting unused for an undetermined amount of time can fail in extremely dangerous ways if plugged into full power (which you can't even do successfully without a power supply). You just don't do this unless you really like gambling. Cap cans are known to explode like M-80's in cases like this. You need a variac. You turn the wall voltage up slowly while checking for cap cans that are heating up (which means they are bad and it should be turned off at once). Slowly like 0-120 AC over an hours time, running up to 60 pretty fast and then 60-120 over the next hour. Otherwise wear safety goggles and have a fire extinguisher nearby. Seriously. It might fire up (with a power supply), but it might also damage something that would have been fine otherwise.

One module at a time best if you can stand the time.

If this is all confusing then find someone to do it for you. Unless you are willing to risk putting it all in the trash after you try. Go do some research on this. Like in the DIY section or other similar forums.

[sthslvrcnfsn]

Well first off, thank you for all the help and advice you've given me, Doug. I had never heard of a Variac before, but the concept makes total sense to me.

If you'd be willing, maybe we could continue this via email or PM instead of taking up posts in this forum. If you don't have the time or energy, that's understandable. I'll just find somebody who does.

I'm going to be making a purchase from Digikey or Mouser in the next week (getting parts to build a pair of TapeOp Omnis mics). I may just go through one of these units, make a list of the capicitors it uses, the specs of the capacitors, and order all new ones. I DO know that capacitors can store charge for long periods of time, and discharge into PEOPLE when they try to remove them. So I would take them off of the PCB board, discharging them appropriately in the process, and replace them with brand new ones. Then I could test out the fixed-up unit with a Variac, and determine what I'm going to have to do to get all of the units up and running again.

Anyways, if you DO have the time and willingness, shoot me an email at mcgowajm@hotmail.com. If you don't, I'm not going to cry about it.

Thanks again for the advice thus far,
-jim!

[emrr]

email sent