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December 10, 2023, 07:00:03 PM

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What kind of fuse was used in my old 1968-69 Univox Univibe?

Started by Diary Of An Axeman, July 18, 2023, 03:20:55 AM

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Diary Of An Axeman

I just fixed the the expression pedal for an old 1968-1969, Univibe .
Plugged it started playing it for a couple of weeks and the fuse blew out .
I did the old aluminum foil tick and found the unit still works, then I unplugged it and  took out the foil and put the unit away.
Would any of you techies out there know what kind of fuses that 1968-1969 Univibes used.
Any help would be greatly appreciated .

joecool85

Quote from: Diary Of An Axeman on July 18, 2023, 03:20:55 AMI just fixed the the expression pedal for an old 1968-1969, Univibe .
Plugged it started playing it for a couple of weeks and the fuse blew out .
I did the old aluminum foil tick and found the unit still works, then I unplugged it and  took out the foil and put the unit away.
Would any of you techies out there know what kind of fuses that 1968-1969 Univibes used.
Any help would be greatly appreciated .

Looking at a schematic, I would hazard a guess that the power draw is somewhere in the 100ma range.  I would try a 250ma fuse and see what happens.  If it is too small, I wouldn't feel bad trying a 500ma (in case my guess of 100ma running load was off by a few factors).  I can't imagine it would need more than that though.

Curious, what size fuse did it have in it when it blew?
Life is what you make it.
Still rockin' the Dean Markley K-20X
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Tassieviking

#2
I saw a schematic that someone traced from an original unit and it showed a 2Amp fuse.
I think that seems a bit large for a tiny transformer.
If it should be a 2Amp fuse it would be fast blow.

If I had any gear from the late 60's I would test and most likely replace any Electrolytic filtering capacitors in there.
At least test all caps to make sure they are still within specs and not shorting out.
If the 1000uF cap is playing up you could do some damage to that little transformer.

Even better would be if you traced the whole pedal and left a schematic here of what you find, there are a few variations out there with different value components in them.

Hmmmm....1968-1969,,,,, I think that's when I first started plucking strings on a nylon string guitar.




There are no stupid questions.
There are only stupid mistakes.

Tassieviking

 Diary Of An Axeman:-
I forgot to say that I love to see photos of the insides of amps and pedals, if you could find it in your heart to open the pedal again and take lots of photos of the front and back of the PCB you might get other people to jump in and trace the schematic for you.

We just need to see the resistor bands and capacitor values etc, it can be a fun exercise to do a trace on old gear to get the schematic for it. Sometimes it's amazing how many variations there are out there.

I have done it a few times for SS amps myself.

Cheers
Mick
There are no stupid questions.
There are only stupid mistakes.