A fellow Hackster gave me the all important Timing and Video PALs for the board. These are quite rare as they can't be read with a simple EPROM programmer so not easily copied. The original program for these has been lost to time so the only way to create new ones is to reverse engineer real ones. While not too difficult it does involve inputting various conditions and see what pops out. The Timing PAL manages the timing for the DRAM refresh and needs to do it in sync with the 6845 CRTC controller. So can be a bit tricky.

But anyway I stuck them in and no joy the clock divisor works ( pins 17-19 ) and LPULSE (12) but DTACKR and RAS, CASL and CASU all stay high. Haven't had a proper look yet. Still need to do some tracing ( its most likely me not the board) may be as simple as something in the reset circuit. I'm not forgetting about the VPAL but without the timing the VPAL won't be doing much.

I  have till Friday to sort it out as I promised to lend them to someone in the UK who is lot smarter than be and will be about to sus it out in a jiffy. 

And this is the pinout for the TPAL.