Sovtek Mig 50

[k00chman]

My Sovtek Mig 50 makes a humming noise for 1-2 sec., then blows a fuse when stnby is switched off. What gives? All tubes light up when in stnby mode.

[Albert Kreuzer]

Something is pulling too much current. Main suspects are power tubes, filter caps, rectifier diodes, power transformer (in this order).
First thing would be to try new power tubes, if the fuse blows again, take her to a tech.

Cheers,
Albert

[k00chman]

Thanx Albert, i did the old chop stick touch trick and eliminated the short. The tubes stay lit now when in opp mode, but no signal to the spkr cab. I'll take it to my tube tech and take no chances. I'm still in the larn'in stage, and the amp is a midget 50H model, with master contl, not a mig 50 as i posted. Oooops.... !! Any mod's for harp aside from tubes? 30+yrs harp / 20+yrs blues. I'v had 10 or more different amps and got this back waaay cheaper than i sold it, and would like to try it for larger venues. Thanks again; Koochman

[distorto]

+1 on the rectifier diodes. They often go bad in these. I have a mig 50 head played HARD for over 10 years everything is stock (except for pwr tubes) I keep waiting for something to break so I can have an excuse to change the cheesy pots and switches but it keeps on tickin'

If your 50H is anything like my 50 it'll be one LOUD ASS harp amp. Let us know how you make out

Chris

[Albert Kreuzer]

A friend of mine plays harp with a 74 Super Reverb (talk about loud ass). I modded the obsolete ground switch to NFB On/Off and he loves it.
Easy mod: You can try to find the wire from the 8 Ohm tap on your 50H that goes to the 56k (I think) resistor and disconnect it. Add a switch or leave it that way if you like it.

Cheers,
Albert