In message <291f01c5d63a$00ee9490$e7bdf682@space.rl.ac.uk> "Alan B. Pearce" wrote: > I'll see if I can persuade my father to find them, and do digital photos of > the pages. That's great - thanks. I've got the cathode and focus grid supplies working fine now, but for some reason the brightness control doesn't have much of a span. I suspect it'll work a lot better once I build up the deflection controls though, but it would have been nice to have the brightness variable over a wider range... I guess I still need to tweak the voltages a bit. The datasheets are great for ideas on what voltages are needed, but utterly crap for "This is what you need to set Vg1 to in order to get rid of the spot" type stuff. It does, however, work, which is nice. I suspect I just need to fiddle with the resistor chain a little more. Maybe move the 100k to the other side of the Intensity pot, put a 47k on each side or maybe eliminate the 100k and use a 220k pot instead. Here are the values I'm using now: 100k 100k 220k 880k (680k+100k+100k) -600V <<<---/\/\/---/\/\/---*------------/\/\/---/\/\/----------------> 0V ^ | ^ | | | | | | | | | Vg1 (inten) Vk (cathode) Vg3 (focus) I also tried adding a 47k pot between +250 and GND with the wiper driving the CRT anode (to allow for astigmatism control), but that loaded down the HT too much. Guess I need to get some more potentiometers, or add a parallel resistor to tweak the ones that I've got... Thanks, -- Phil. | Acorn RiscPC600 SA220 64MB+6GB 100baseT philpem@philpem.me.uk | Athlon64 3200+ A8VDeluxe R2 512MB+100GB http://www.philpem.me.uk/ | Panasonic CF-25 Mk.2 Toughbook Tagline? What tagline, Officer? I didn't see no tagline. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist