>
>> I've found with my Henry that using the old "dip and load" technique
>always
>> leads to the best operating condx
>
>snip...
>
>> With modern gear there sometimes is a tendency to simply tune for max
>output without paying
>> close attention to the grid/plate.
>
>snip...
>
>Thanks, Dave. I'm glad somebody finally said this. I've seen a lot of posts
>here about tuning for max output, and I've never been able to reconcile that
>approach with the old "dip and load" technique I learned with my first tube
>transmitters back 15-16 years ago.
>
? A Pi-network tank is Not the same animal as a parallel-resonant tank.
A Pi-network is two L-networks in series. L-networks are never resonant.
An enlightening dose of reality is to tune up a Pi-network tank
amplifier at full suds, shut down, unplug from the electric mains, wait
until the hv meter goes to zero, and measure the resonant frequency of
the Pi-network tank circuit. . What! The tank resonance is lower in
freq. than the operating frequency? No way!. . This must be a trick,
right?
- It is my opinion that for a Pi-network tank, dip and load is not the
right road. Better to start with heavy loading (minimal C-load) to
reduce dissipation in the grid, apply max. drive, and tune for max.
P-out.
? Grid-dissipation can not wax when P-max is going down the coax.
- cheers
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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