Thread: Pye Black Box
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Old 17th Apr 2012, 4:13 pm   #8
Radio_Dave
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Default Re: Pye Black Box

Quote:
Originally Posted by Nickthedentist View Post
Look out for the OP tx being open-circuit on one half of the primary
Just checked the output transformer and one half of the primary is open circuit.

I used the good half of the primary to calculate the turns ratio and arrived at, about, 110:1 (I think it should be 100:1). I've got an output transformer, from a Pye Fenman II, which has a turns ratio of 93:1. I imagine this would be close enough?

The Black Box had a primary resistance of 1700Ω but the Fenman II has only 660Ω. I don't understand the significance of this DC resistance, hopefully somebody will explain.

Regards
David
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