[TowerTalk] Bazooka antenna

[Jim Brown]

On 11/9/2011 7:31 PM, Rob Atkinson wrote:
> Put your GOOD rig and amp on 3595 and put 1500 w. CW into your coax to
> your fan dipole and have a listen to what comes out on 7190.

I've done that -- in fact, I do it pretty often when i run SO2R, as I 
did both of the last two weekends.

> Have a ham listen a couple miles away.

I've been doing that for at least 40 years, usually with the guy on the 
other end being a damn good engineer, and I've listened to him under the 
same conditions.

> Who told you it was a good rig?  The manufacturer?

Nope. I've measured some that I've owned, and I've studied test results 
by good labs. FWIW, I can run my two K3s, each driving a 30-year old Ten 
Tec Titan amp at legal power, into 3-el Yagis that are about 150 ft 
apart, within about 50 kHz of each other ON THE SAME BAND. I did this on 
20, 15, and 10 during CQWW SSB ten days ago. At 30 kHz spacing, I could 
clearly read S5 signals, with some phase noise from the other rig. At 
50-60 kHz, I couldn't hear my other rig unless I happened to tune to an 
intermod product, which would typically be S9 or so.

> There are thousands of tribanders, trap verticals, and beloved fan
> dipoles and now, thousands of solid state broadband boxes overdriving
> s.s. garbage amps.  Maybe you should add something about a low pass L
> network tuner to your tutorial.

I'd rather warn folks about REAL problems that are FAR worse -- phase 
noise making signals ten times wider than they should be, key clicks, 
and splatter from intermod distortion at both AF and RF generated both 
by the transceiver and that garbage amp (or by a good amp that isn't 
properly tuned). Yes, L-network tuners in a low pass configuration are 
nice, and I have six of them on my operating desk, all tuning wire 
antennas.

About a year ago, I added the Elecraft P3 spectrum display, and have 
been watching signals -- mostly CW, but sometimes SSB too. There are 
HUGE differences between the -50dB bandwidth of a K3 (about 400 Hz) and 
most other rigs (often 5-10 kHz).  If you want to go on a crusade that 
means something, tackle THAT!

73, Jim K9YC