In a message dated 3/13/2011 3:39:14 A.M. Eastern Daylight Time,
km1h@jeremy.mv.com writes:
Losses in your typical commercial tuner are in the inductor as the low C
used on 80-160 are the problem. This was shown decades ago in ARRL reviews
of available tuners.On 160 in particular it was shown that a "matched"
condition was possible with the inductor absorbing the full power.
Enjoyed reading all the comments on tuner loss. It looks like whatever we
do, don't skimp on the inductor.
The best way to keep tuner loss low is to use the heaviest inductor
practical
in a large box with the best roller contact available and pay attention to
coil 'Q' and have enough 'C'
available on the input and output side to be able to reach a matched
condition with
the least 'L' using the 'T' network configuration.
Probably best to use high-current vacuum variables for the 'C'.
Also looks like it would be best to have separate tuners, one optimized
with larger 'L' for the
lower bands 160-80 and another tuner with a smaller value inductor
optimized for 40-10.
73 - Todd WD4NGG
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|