Yo! Bruce:
Monday October 07 1996 18:05, Bruce Clark wrote to Bill Cheek:
 BCh>> And so it is that any two antennas in close proximity with each
 BCh>> other WILL interact to produce some effect, typically undesirable.
 BC> My experience on a 75 Honda Civic:
 BC> 1 CB ant., 1 465MHz UHF ant., 1 18" scanner ant., 2 cellular ant.
 BC> all in an area 30" square.
 BC> The cellular are more then one wavelength apart and not on the
 BC> quarter wave multiple.
 BC> As long as the antenna are not close to being tuned to the same
 BC> wavelegth they don't interfer. At least before and after standing
 BC> wave checks have led me to believe this. Mounted one antenna first,
 BC> then the other, then both.
Well, the elements of a log-periodic antenna are not all tuned to the same 
wavelength or even close.  There is always some interaction between any two 
adjacent antennas, regardless of their resonant frequencies.  I agree that 
the farther apart in frequency they are, the less the effects .... usually.
The VSWR of any given antenna in proximity of another is not always affected, 
so you can't go by that.  The proof of the pudding lies in radiation pattern 
tests in a 360-degree azimuth around the vehicle.
Bill Cheek | Internet: bcheek@cts.com | Compu$erve: 74107,1176
Windows 95 Juggernaut Team | Microsoft MVP
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