Thanks all for the replies. I managed to change the divider again, no real change. Playing with R16 helped a bit, but basically the output is unstable from the divider. Just putting a finger very near the divider plastic body will get it going, but often the square wave forms go out of 90 degree phase shift and dither about. I am wondering if such a low frequency oscillator could be bread boarded and optimized somehow on there rather than pulling stuff off the board with a real risk of damage? I will try 220Pf forC12 though, thanks edavid. can anyone suggest values for C10 and C11 that should work, is there a way of calculating them? I am not sure if I have any spare 2n3904 and 3906 devices, I may have to buy some unless they are very none critical? I'll also put back the 22k for R16 if you think I am changing it needlessly. Thanks for all the advice, this is the waveform on R17 to pin 3 I now see.
Andy, if I build on a new PCB should I either try and get exactly the same divider as the kits came with, or go for a slower one? I don't want to change too much willy nilly as I am easily confused!
Have a good weekend. I was hoping this simple RX would be a walk in the park, I am managing to get my home brew TX set up into the US as I type, I am embarrassed that I am struggling to get a simple SDR RX running right!