Jim: You are correct about installing terminating resistors at the ends
of rombics, v-beams and long wires. This is only for the purpose of
causing the antenna to become directional off the terminated end.
If the antenna terminating resistor is removed, the antenna will be
bi-directional, i.e. radiate off both ends. Terminated rombics and
v-beams were in common use with the military who desired a fixed,
point to point antenna to communicate great distances. However,
when yagi's became developed and popular in the 1950's, they
gradually, but not completely, replaced the rombics and v-beams
because they did not require so much land and they could be rotated.
For the rombics this type of resistive termination is discussed in some
of the older copies of the ARRL antenna book and would require a
noninductive type resistor. These large rombic antennas were fantastic
performers and were aperiodic with tremendous bandwidths. Another
advantage they offered is they could achieve a very low angle of
radiation without extreme height. They were always fed with
open wire line. For amateur use, the major drawbacks are the large
amount of land they require and they are only single or bi-directional.
>From what I can remember, they were the type preferred by
commercial telephone carriers when world wide point-to-point
hf telephone service was developed in the 1920's and '30s. Based
on a rough estimate, I would expect any antenna that has a
resistor inserted in its center or feed point would perform very poorly as
at least 50% of one's transmitted rf would be dissipated as heat and
likewise for the received signal. The Maxon (sp?) tuner was a
fraud that was perpetrated on unsuspecting amateurs. Fortunately,
it was exposed by the ARRL in the QST article that you refer.
- 73's- Corn - k4own.
Corrupt politicians love unarmed serfs.
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