30-06-2012, 01:00 PM
Lawence,
I've also had a look at ECH42 and ECH81 data. They both say around 18V RMS, again if I've translated the graphs properly. I suppose you might expect later valves to be less 'thirsty' due to the smaller geometry.
I guess the real method is to inject variable signals into the grids and measure the wanted output, which is presumably what they did.
The graphs are fairly flat around the maximum Conversion Conductance so it presumably isn't too critical, which is just as well as the level is bound to vary with frequency, ageing etc.
Alan
I've also had a look at ECH42 and ECH81 data. They both say around 18V RMS, again if I've translated the graphs properly. I suppose you might expect later valves to be less 'thirsty' due to the smaller geometry.
I guess the real method is to inject variable signals into the grids and measure the wanted output, which is presumably what they did.
The graphs are fairly flat around the maximum Conversion Conductance so it presumably isn't too critical, which is just as well as the level is bound to vary with frequency, ageing etc.
Alan
