i have a tube amplified portable reel to reel which has a design that connects directly to ac which i would like to add an isolation transformer to - however the one i currently have is a tight fit.
so i was wondering if anyone might have any ideas of a smaller isolation transformer that they might recommend?
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the unit i am adding isolation to wants 115 AC, 60VA 60C/S (according to the plate on the outside of the unit)
the isolation transformer i have on hand is 115 AC, 80VA dimensions 2.5"h x 3" x 2.75" - it is a tight fit and i would have to modify the case a bit to get it to fit (to gain about 1/4" or so on the height)
i mainly need one that is shorter than 2.5" h - i found this toroid unit, but it is 117V ...
it measures 1.52"H×3.73"O.D - so that one might fit... i'd have to build a dummy to know for sure if the diameter is okay
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just curious if anyone has any suggestions for a space saving isolating transformer for my application...
thanks!
here is a schematic of the unit i am adding isolation to:
so i was wondering if anyone might have any ideas of a smaller isolation transformer that they might recommend?
_
the unit i am adding isolation to wants 115 AC, 60VA 60C/S (according to the plate on the outside of the unit)
the isolation transformer i have on hand is 115 AC, 80VA dimensions 2.5"h x 3" x 2.75" - it is a tight fit and i would have to modify the case a bit to get it to fit (to gain about 1/4" or so on the height)
i mainly need one that is shorter than 2.5" h - i found this toroid unit, but it is 117V ...
it measures 1.52"H×3.73"O.D - so that one might fit... i'd have to build a dummy to know for sure if the diameter is okay
_
just curious if anyone has any suggestions for a space saving isolating transformer for my application...
thanks!
here is a schematic of the unit i am adding isolation to:
An externally hosted image should be here but it was not working when we last tested it.
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My suggestion is not to isolate the motor. That should reduce the load sufficiently to use a smaller transformer. The heaters draw 150 mA and the plates maybe half that, so you have a load less than 1/4 A, and a 30 VA transformer might do it.
The next step in reducing the load would be to allow the heaters to remain on the line and just isolate the plate of the rectifier. I don't like that, as it may create excessive heater-cathode potentials that could cause hum or even tube failures.
The next step in reducing the load would be to allow the heaters to remain on the line and just isolate the plate of the rectifier. I don't like that, as it may create excessive heater-cathode potentials that could cause hum or even tube failures.
oh that sounds great - i was actually planning on not isolating the motor anyway (as it is a pole motor and has its own transformer already) to keep the heat down on the isolation transformer
i think there is a cheap 50VA transformer i know of that will fit nicely in the unit - i just didn't know how to determine the VA i needed other than what the case said...
thanks so much - i'll give it a shot!
i think there is a cheap 50VA transformer i know of that will fit nicely in the unit - i just didn't know how to determine the VA i needed other than what the case said...
thanks so much - i'll give it a shot!
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