[TowerTalk] Bazooka antenna

[Jim Brown]

On 11/10/2011 6:06 AM, Rob Atkinson wrote:
> I submit that a detectable 2nd harmonic qualifies as a real problem
> especially if it is out of a ham band.

You might want to study FCC Rules on the subject before making that 
statement.  They are, in general, tied to the extent of harmonic 
suppression below the level of the fundamental, and to "good engineering 
practice."   A harmonic will get you in trouble only if it happens to 
fall on a frequency used by another service, and is strong enough to 
cause interference to that service.

If your equipment meets industry standards for harmonic suppression and 
is properly tuned, it is unlikely to do that.  If you're using junk, or 
don't bother tuning it carefully, you're more likely to have a problem.  
FWIW, the FCC can't even keep illegal CB operators running 500W junk 
amplifiers off of 10M (although they ARE trying), and that's at least 
30dB stronger (1,000X the power) than the harmonic from a type-accepted 
1.5kW transmitter. Try tuning around 28.025 or 28.085 and you'll hear 
what I'm talking about.

73, Jim K9YC