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Arfa Daily Arfa Daily is offline
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Default Boss GT5 guitar multi effects pedal ...


"Dave M" wrote in message
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"Arfa Daily" wrote in message
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Anybody by any remote chance got schematics for this thing, or know the
(voltage) specs for the power transformer. Funny slimline core. Primary
o/c :-(

Two secondaries by the looks of it, one CT, the other not. Worst case, I
could probably graft two separate transformers in. If no one has the
transformer data, then I'll just have to make an educated guess, based on
the filter cap voltage specs.

TIA

Arfa


Any chance that you can open the wrappings from the windings and see if
there's a thermal fuse in there that's opened?
If not, maybe you can get a bit of an idea if there are any voltage
regulators in the power supply that you could use to derive one of the
secondary voltages. Once you have that, just apply that voltage to
winding and measure the voltage on the other winding. Derate by about 10%
and you should be pretty close. Out of circuit, of course.
Use your best judgment on the VA rating of the transformer. Use catalogs
from various manufacturers such as Hammond, Signal, etc. to get size vs.
VA estimates.

Dave M


I'm sure that there's gonna be a TF buried in the windings, Dave, and that
it will be open, but unfortunately, there's not anything that you can see -
even just its wires to whack a short across to get the tranny temporarily
running to measure its secondaries. All of the things that you suggest for
determining its ratings by 'guesstimate' are exactly what I would be doing
too, just thought I would post in case anyone had a definitive answer, to
save me the trouble of having to work it all out ...

Thanks for your thoughts :-)

Arfa