[TowerTalk] N6AW on 30m BIG GUN SIGNAL

[w8ji.tom]

Hi Josh,

You wrote:
> The other night I heard someone working
> Europeans and Russians on 30m 
> Most of the DX I could barely hear !!
> He said that he was using a Rhombic  350 meters
> in over- all length  aiming Europe.
> HE was putting out an absolutely awesome signal !! with 200 watts!
> getting 599   from ZS6QU   off the side.

Of course I can't say if what you heard was "real or Memorex", but I'm
skeptical about antennas provide exceptional gain in all directions at all
distances.

A Rhombic 350 meters on a side (11 wavelengths) would have a fairly narrow
main lobe. Unless Russia is almost in line with England from W6, it would
be too narrow to cover both.

Gain would be about 12-15 dBd in the main lobe, because the
antenna "gain limits" at about 3 or 4 wavelengths per leg.

Also consider that having a "booming signal" off the side means a lot of
energy was not available in the main lobe. How can an antenna have high
gain and super performance in every direction? Does that make sense?

> Can  Rhombics be effective with Metal supports?

Sure. 

> I always here about the tall telephone poles supporting Rhombics?

It would have to be a tall pole! Rhombics, to minimize earth losses, need
to be at least 1/3 their leg length above earth. 

The main advantage of a Rhombic is the very wide useable bandwidth. If you
want gain, there are much more real estate friendly ways of doing it.

73 Tom

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