Tube CAD/SE AMP CAD

[Global]

Being readily impressed by pretty pictures, tired of cooking up purpose-built spreadsheets and impressed by the Ian's posting from these programs in the '845 Amp' thread, I decided to acquire a copy.

Right - all I have to do now is figure out how they work!

The manuals with the programs are helpful but relatively simplistic.

Are there any web resources to help to 'get the hang' of these progs?

My particular source of puzzlement at the moment is the calculation for the 'symmetrical SRPP' circuit, which is the first stage of the 845 amp. This model seems to let you put in any values for HT and stage current and gives you the cathode resistor values in the 'calculated values' bit.

Do you plug these values back into the model or what?

Thanks

Mark

[Max N]

Hi Mark
Yes, plug the cathode value back in and re-calculate, after a couple of iterations the calculated value will match the one typed in.

[Ianm2]

you have to get the anode current about right to match the calculated cathode resistor, that takes a bit of getting used to, just use it, play around and see what you get.

start of with the b+, the psu voltage,

you can largely ignore the coupling cap and grid leak resistors to start with.

both resistors in the srpp are the same value, btw.