SOVTEK Mig Output Trasformer

facemannings · Newbie Alert Joined: 05 Dec 2007 Posts: 3

Hey everybody... My first post here.

I have a Sovtek Tube Midget, and I managed to blow up the output transformer (long story). Anyway, there's no markings on it at all, and I've not been able to find anything online that gives me a P/N or anything... or an accurate schematic for that matter. It's actually kinda hard to find any info about Sovteks in general.

Anyone know anything about them??? Or a place to look? Thanks dudes- PR

tw001_tw · Puppy Joined: 26 Mar 2007 Posts: 205 Location: St. Louis

welcome facemannings. I have a fondness for Russian stuff, but never
had the cash or need to by a sovtek.. although if I win the lotto one day
(not that I play the lotto Rolling Eyes

)

Anyway - verify my info - its a 50W amp with 2 5881 (6L6) power tubes, right?
If so, all you need is a 50 or 60 watt, PP output transformer with 4,8,& 16 ohm
secondary taps. Something along the lines of a hammond 1650N. The
worst case should be that the primary impedance will be a little off, but
should be at least close to the right range - chances are you won't be
able to tell.

Double check my facts and good luck!
-tw

facemannings · Newbie Alert Joined: 05 Dec 2007 Posts: 3

Yep... 50W w/6L6's....

Thanks for your help! I was looking at the hammond MFG site, and noticed that the 1650P also sounds suitable, but it has a higher impedance. I'm no genius, and I don't really know much about that sort of thing...

the forum wont let me post a link... so you'll have to look at Hammond's site

The primary impedance is measured in 'ct' on this site... what does that mean? Also, how do I figure out which impedance would be more suitable? The leads for the transformer come right off the tube socket... if that means anything. If I have to guess which impedance would be better, what would be better to shoot for... lower or higher... how would if affect the sound? High end roll off?

Thanks again for being so helpful!

tw001_tw · Puppy Joined: 26 Mar 2007 Posts: 205 Location: St. Louis

"Also, how do I figure out which impedance would be more suitable?"

Ah.. sorry to say, but I don't know. If the old OT was good, there is a
way to measure it, but its reather complicated. Most amps I know of
are in the range of ~4000 to ~8000 - so 6000 is a good safe bet. It
would work with anything in that range, but it won't sound 'optimal' as
the curcuit is designed for a much narrower range. Once you replace
it, I would, if I were you, rebias the tubes (or take it some where that
can rebias them for you. Its almost a toss up between the 1650N which
can handle more power or the 1650P which primary impedance is closer
to a 'middle' range.... its tought to say which is best without specific info
regarding the original OT specs. There might be some technical tricks
that could narrow it down for you, but its a bit byond my confidence level,
especially to explain it. sorry!

facemannings · Newbie Alert Joined: 05 Dec 2007 Posts: 3

thanks for the info... I'm going to do some more reading and see if I can figure it out. I'll post the results.