I appreciate your input Marty... im on a steep learning curve here with valves and having to dig out of my memory all my AC theory I did when I did my electronics course... its very true, if you don't use it you lose it as im looking at my old notes and struggling to make sense of them... oddly enough, at the time, I much preferred AC theory to DC!

It seems that my opto multiplier might require the high voltage as most are a high voltage high impedance device..... wish I knew more about these things