Rick Williams - VE7TK
Thanks to all who have responded.
I have found that I do indeed have a 20 MHz signal on pin 9/10 of the controller (apologies to all I must have miscounted).
However, the symptoms have not changed.
Alan G1FXB - I have 5 VDC on pins 7 and 20 of the controller (IC2).
Sven DJ2AT - I agree that one of the fuses is likely messed up or worse and it may require a new controller chip.