RE: NEC-LIST:Loaded dipoles

At 10:00 AM -0500 2/25/02, John B. Wood wrote:
>>Resistive loading of the antenna accomplishes nothing but to
>>dissipate power. If dissipation is your goal, you can get it more
>>easily with a resistive pad in the feedline between the antenna and
>>your transmitter and/or receiver. The only advantage of
>>distributing the resistance that I can imagine is to dissipate the
>>heat into the air more easily.
>
>Hello. The above statement could arguably be correct for a
>narrowband antenna but is not correct when designing a broadband
>antenna that is required to operate over multiple octaves.
>Resistive loading schemes on antennas are implemented to achieve.
>across the operating bandwidth, the optimum trade-off among antenna
>gain (efficiency), pattern shape, and feedpoint VSWR (acceptable
>transmitter mismatch, say < 3.0). Although a resistive attenuator
>inserted between the antenna feed and transmitter might be a
>solution, it does not necessarily represent the optimum solution for
>the transmitting system architecture. One well-known example using
>a simple dipole is Edward Althuler's paper, "The Traveling Wave
>Linear Antenna", IRE Transactions on Antennas and Propagation, vol.
>9, pp. 324-329, July 1961. Sincerely,
>...John Wood

Wasn't Ed Altschuler's "Traveling Wave Linear Antenna" loaded with
series capacitors, and not with resistors?!

-Chuck.

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