Cheers Bob - really didn't want to rewind it so I very carefully soldered an extension to the shorter wire so I could reconnect to it's pin. I think I might have done it
- the 230v coil is showing ~2.7Kohm, and when connected to 250v (grid) and secondary is showing something of the order of a volt (ac voltmeter sensitivity issue) - I did think that was low until I traced the circuit to the AD736 and read the datasheet showing 200mV input so it may be OK.
resoldered onto the board, but I think that that was a secondary issue from the unit being dropped at some point. The primary fault seems to be one bank of FETs has blown (shorted drain-gate and a leaky open circuit D-S) so i'm going to sub 2 or 3 of them and test again.
the main trans work fine when disconnected from the pcb and used in reverse on grid power.