2 at vc.net wrote: > € The RL of an 8171 is c. 1200‡, so, at 50MHz, a total C-Tune of roughly > 80pF is needed for a Q of 15. Since the anode-screen C, stray C, and the > neutralizing bridge total c. 30pF, a 50pF Tune-C should do the job. > I guess that value of RL is at 15KW output power, so at 1500W it will be much higher and C-Tune need to become much smaller 73 Peter