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Heater question - grounded?

I'm building a GA-5 using the Mojotone Kit. I added a switch, so I can have switchable NFB. I have it all wired up. I was about to do the startup testing, and the first thing I did was test the heater wiring continuity. Should I expect a short between the two heater leads? Should I expect them to be shorted to ground? I got shorts when testing in both cases. The latter part seems especially odd to me. After doing some digging, it looks like I should expect a short with very low resitance when measuring across the taps of the transformer, so then across the heater wiring should be same. Does the short to ground make sense, though, or do I have a wiring issue somewhere?


It is perfectly fine. You measure the resistance of the heater windings on the transformer which is a relatively short number of turns and with thick wire (low voltage, high current) = low resistance. The center tap is connected to ground and therefore they both also seem to short to ground.
See the circuit diagram


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