[BC] BE tuner and such

[dynotherm at earthlink.net]

The complex conjugate method is a valuable way of setting the entire
network intact, it is preferable to calculate the individual branches
and set them by breaking the center of the tee and grounding the input
and output first. After each leg of the tee is set at the calculated
value and the center reconnected then using the complex conjugate 
method for SLIGHT, final readjustment will give the best result, but
that did not appear to be what he was talking about.

As I understood it, he was asking if it might be useful to sweep the
ATU end of the coax while the other end was connected to the Tx. In
this case he would be looking back through X deg of delay at the
combiner output. IMHO, Cowboy gave a very good answer to that question.
The only thing I can add is that knowing the exact delay of the coax
would have an effect on the outcome so that should be determined from
open and shorted measurements first. Thus, in general, looking into
the TX end of the cable may be more meaningful to most and can be done
more easily.

WRT the BE matching unit, it is possible to make a true 90 deg tee
from a fixed coil, a mica cap, and two roller coils and get something
easier to adjust because it is truly conventional and is specific to
the station's frequency. While this is not cheap it does give a little
bigger band for the buck and should be less than the BE unit.

Phil Alexander, CSRE, AMD

-----Original Message-----
>From: Dana  Puopolo <dpuopolo at usa.net>
>
>That is a valid way to pre-tune a network. Put a 50 + j0 load on its input and
>measure it's output (tower side). Adjust the network for the CONJUGATE value
>(if the tower bridged 
>30+j24, you adjust the network for 30 MINUS j24).