[Towertalk] Force 12 vs. Cushcraft who wins?

[Pete Smith]

At 09:52 AM 12/2/02 -0600, n4kg@juno.com wrote:
>Pete,
>
>Please explain WHY you would think a 24 ft boom TH7 would have
>a higher F/B than a 14 ft A3?  It is a well known fact that 2L
>parasitic Yagi's have relatively LOW  F/B (<15 dB, often <10 dB).
>

Sorry, I probably short-handed that a bit too much.  My models showed the 
TH-7 with ~18 dB F/B on 20m and nearly 25 dB on 15 and 10, when measured 
above ground (at 97 feet).  Since the TH-7DXX has a 2-element driver cell 
and an extra element on 10m, my guess is that it doesn't follow W2PV's 
dictum that closely.

I respectfully doubt that an A-3's F/B ratio can match the TH-7 on any 
band.  The Mosley TA-33, which also has a 14-foot boom, showed only 8.1, 
9.0 and 6.5 dB F/B respectively, on 20, 15 and 10, in the K7LXC/N0AX 
tests.  By contrast, the TH7DXX showed 14, 13.6 and 11.2 dB 
respectively.  I've said before that I think the absolute numbers are iffy, 
but the relative values tell a fair tale.


73, Pete N4ZR
Sometimes a tower is just a tower