The approximate reflected Z is about 15k, using 300R load to the secondary.

Primary volts swing is about 30V RMS, using the toroid (240:30V) - primary L= 6H and lossy capacitance is a whopping 0.5uF!

Turns ratio comes out to something like 6.7:1

So far I have found Edcore XSM 10k:150 (oversize but tolerant of the voltage requirements)

Hammond 107V, which looks tiny...DIP mount???

But also has good primary inductance, 25k:600R, and appears to be suitable for an input level of 30V RMS.

Thus either OPT above, I am either using a lower Z tap for a higher load R, or vice versa.

Any suggestions, hints or advice, to help me select one of these OPT, or perhaps another more suitable, is gratefully received.

Thanks