[Amps] Ceramic capacitor ratings

[Peter Chadwick]

Gary,
I would argue that if the impedance presented to the plate is the same, then the loaded Q should be pretty much the same. The laod impedance that the plate sees affects directly the power output, so for equal everything else, the laoded Q of the tank ought to be the same, and thus the circulating  current,
The impedance across the input of the pi is determined by the component values: if the loss goes down but the values stay the same, to a first approximation, the input impedance is the same. So if it's tuning with different values, it suggests that it not just the inductance and q in the coil has changed. But, if the loaded Q is constant, and the capacitor values are constant, the circulating current at any power level must be constant. The loaded Q is a function of the impedance that the network offers to the plate of the tube.
There are arguments about whether or not the impedance offered to the plate of the tube is the complex conjugate of the tube impedance: I don't intend to open this one up here, but merely say that there are conflciting opinions, wherein I hold one, (in common with people like Warren Bruene), and Tom. W8JI and some others (such as Professor Belrose, so you can hardl;y discount their arguments as coming from people woithout a good technical background) hold a trotally opposing view! Such arguments have the advantage that, being somewhat akin to the mediaeval one of how many angels can be placed on the head of a pin, afford the possibility of hours of innocent (but occasionally vituperative) argument.
73
Peter G3RZP