Hey Malcolm, I just read your bit about 'resistors', I actually solder in, what 
I believe, is a resistor.  Make sure nobody else reads the following, 
but.....are resistors those tiny ceramic things that have little bands of 
varying colours and with a wire passing through it?  I did some research on 
those and apparently the colour bands denote...is it milliamps?  I downloaded a 
chart with the colours and what they represent and mine has a red, (could be 
orange as I can't tell, even with glasses on as they are so small), a white and 
2 black bands and on looking it up it reads, I think, 290 whatever, or 390 
whatever.  This wouldn't be a current limiter would it?  It actually gets warm 
when unit is 'working' also which suggests to me that it is a limiter.  The 
'backpressure' with water thing?

I bought a generator years ago and have been altering that generator, well the 
generator I bought was probably made in someones back shed anyway but the 
design of the inner workings would still be the same, I'm just making slight 
alterations to how it goes together for cosmetic purposes, eg; removable 
electrodes instead of soldering them onto a board.  Banana connectors for the 
electrodes so that the unit stores away neater if you see what I mean.

Neville.