Miko's Unilevel Work in Progress.

Not too long ago I put these in the Black Market. When I realized nobody wanted them, I was stuck with them. So I might as well use them. :wink:

Old School, utilitarian, and grey. Big old ADC output transformer. Cute little UTC input. I'm hoping they sound as cool as they look. Here are some pics of the modules before I get them in a rack and powered up.

The pair hanging out together.
http://img.photobucket.com/albums/v473/MikoKensington/Unilevels.jpg

Input transformer and one of the NOS connectors I found.
http://img.photobucket.com/albums/v473/MikoKensington/unilevelinput.jpg

The tube compliment is a 6386, 6AL5, and two 6V6GT's. The 6AL5's I put in are NOS JAN 5726 substitutes. The 6V6's are NOS JAN's as well. I need one new 6386 for sure. The one I have may need replacing.
http://img.photobucket.com/albums/v473/MikoKensington/unileveltubes.jpg
http://img.photobucket.com/albums/v473/MikoKensington/unileveltubesA.jpg

Schematic.
http://img.photobucket.com/albums/v473/MikoKensington/Collins_356E-1.jpg

This should be a pretty simple and fun project to do. I'm sure before the end I'll be pestering you all. More updates coming...(soon?)

-miko

Nobody wanted them?

You gotta admit, they were priced like you didn't really want to sell them. Confess! :razz:

I don't know, $300 each doesn't seem an outrageous price. Who knows? When these are up and going I may never want to part with them.

Well, bear in mind, I'm what you might consider "cheap"... Mainly because I remember when you could pick this stuff up for cheap at hamfests, or for free from broadcast station junk piles :wink:

Oh, and this is only going back ten years or so. The whole "vintage" market has really exploded over the past few years.

I really think $300 is a nice offer. Too bad I don´t have the money at the moment.

I missed these on the black market. Are you willing to still part with one or both?

MM1100 said:

I missed these on the black market. Are you willing to still part with one or both?

Click to expand...

What's an couple days when your maybe 5 years too late?

Ha - yikes! Should have checked the date - anyway here are a few pics of a Uni that I racked/modded.

Check out Miko's Unilevel on the right, particularly the output tranny. Compare that to the scratch pattern of the one I racked. They are the same amps!!!!

I'm not surprised.  I probably owned one of them once too!

Well Miko's Work in Progress is finally complete for one of the the two. What happened to the other one?

I sold one to jrmintz, I don't know where the other one went.  I got mine from a retired engineer, I think.  Man, I've hand so many pieces of gear pass through my hands, it's hard to remember.  

Seth (jrmintz) had his up for sale a couple years ago.

Is the input transformer really 600:600 or have I misread the winding diagram?

I thought for sure this was a high ratio step up input like most vari-mu.

600:60K

I know that's what the schematic shows. However,  Miko's pic shows a different model number, and clear wiring diagram with "600ohm" on both pri and sec.

The pictured xfrmr is labeled:
UTC K-9459
GE A-7139209

oh, I see.  That's been replaced with the wrong input. 

The GE BA9A plug in UNILEVEL shows a matching model number (see pic). I thought it was odd to see a UTC on the input vs. the later used ADC. The amp sounds fantastic along with matching the model number. What's up with the 600ohm 600ohm? Is that a misprint?

I have the full documentation on this GE plugin model. Has a different pinout/connector than the Collins 356E-1 version. Also I always use the rev. A update from GE that has a few slight circuit mods that the Collins schematic does not show.

Let me know if you would like me to send a scanned copy of the schematics/text to you.

Nathan

It's probably a misprint then.    One version of the GE preamp uses UTC's; the first of the circuit board types, I think. 

Not that it depicts the input secondary, but I thought it would be relevant.

Cool - that's the revision A. Compare to the Collins 356E-1 to see the diff.