[Amps] Effects of load Z mismatch?

[Jim Kearman]

> For AC, the problem becomes a lot more complex (excuse any pun).

Frank Carcia gave me the insight I needed. As I'm using tetrodes I have been wrestling with k in 

ZL = Ep / k * Ip

So I got numbers between 1460 and 1820 ohms. Thanks to the insight, I ran the numbers over the Qo range of 12-15 for ZL 1500-1800. It turns out that the same plate tuning capacitance and inductance, with variations in loading C, will match that range of impedances while keeping Qo between 12 and 15. If I make my loading cap big enough I have confidence that the amp will function properly as built, within the recommended range for Qo. Even better, I have all the padding caps I need except for one, which I was able to find at a very reasonable price, thanks to WC6W. If the guy who paid $58 for a 1000-pF Cardwell variable on eBay last night is reading this reflector, it would behoove him to check out WC6W's list of goodies. 

73,

Jim, KR1S
http://kr1s.kearman.com/