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does anyone know where i can get a replacement for the input transformer for this amp? it has 3 sets of numbers on it, they are 32ac020 189a3 892523. can these numbers help in any way?
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The numbers don't tell us much.
Schematic Heaven has the 703, even in several versions. Get the drawing for yours and see what it says. I am assuming you mean the power transformer?Education is what you're left with after you have forgotten what you have learned. -
thanks for responding. i have not got the chance to go to schematic heaven cause my home computer wont let me but i do have a schematic from the tube amp book and this really does not tell me much other than it is a step down. they label it as t1. now is this actually considered a power transformer because the lineup of tubes equal 114v? i have heard this referred to as a transformerless amp. is this correct?Comment
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T1 is the power transformer - it transforms the AC mains from 120v into whatever high voltage the curcuit needs. There is no heater winding, those tubes are the clasic series string of heaters. 150 ohm R3 takes care of the last few volts. In a transformerless amp even the high voltage is directly connected to the mains, this is not one. Your transformer makes it MUCH safer.
It looks to me like a simple isolation transformer would work - that is a straight one to one 120v in and 120v out. With the loss through the rectifier tube, it ought to be about right for the voltages noted. As a caution, I might try to find a tranny with slightly lower taps.Education is what you're left with after you have forgotten what you have learned.Comment
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