For FB group Building Transistor Radios
This is the idea that I had about using more than one transformer to connect their windings in series or parallel to get a higher impedance and a higher stepdown ratio. My idea was to be applied to the Bogen T725 line matching transformer, but it could be applied to any 2 or more transformers.
What I drew was a pair of transformers with their primaries on the left connected in series and their secondaries on the right connected in parallel. They must be connected properly, in phase, so they don’t cancel out each other.
When the windings on a single transformer are connected in series, the impedance is equal to the number of turns squared. This is because the voltage is double, but the current is halved.
But I don’t know if this ‘number of turns squared’ still applies to two transformers connected as shown in the diagram. In any case the series connected windings still have a higher impedance than a single winding. I guess the only play 2 find out would be to measure the voltage and current with the connections as shown.