I have a Mosley Classic-33 (CL-33M) triband antenna that doesn't seem to
have the "punch" that it should. It replaced a PRO-57 and the
difference is like daylight and dark (why did I replace the PRO? Long
story involving modifications for the WARC bands....). On 20, 15, and
10 meters, I could bust the biggest pileups with the PRO. The PRO has a 24
foot boom and 3 active elements on each band. The CL-33 has an 18 foot
boom and 3 active elements on each band. Maybe a little difference in
gain, but not daylight and dark... The new and old antennas are on the
same tower at exactly the same height (56 ft) with the same feedline. The
SWR on the CL-33 looks normal, and it seems to have normal F/B on 20 and
15, but only about 5 - 10 db on 10 meters. I attributed that to the overly
wide spacing on 10. However, it just doesn't get out. DXpeditions are
now difficult to work, even running 600 watts out. I usually got ?em on
the first day with the PRO-57, which wasn't that great an antenna compared
with others.
While studying the instructions I noticed the reflector on the CL-33 is 25
feet long (phone setting). The driven element is approximately the same
length (a foot longer with CW setting) but that is explained by the fact
that the classic feed system is a capacitive feed and requires a longer
D.E.
I got curious when I looked at some other Mosley manuals. The TA-34XL is
a similar antenna, but with 4 elements. The directors (and
D.E/reflector spacing) are within a couple of inches of the CL-33 (The
D.E. is shorter due to direct feed) but its REFLECTOR is nearly a FOOT AND
A HALF longer than the CL-33's! The reflectors on the TA-34XL and the
CL-33 have identical 25 and 15 turn trap coils, so this isn't the answer.
The other manuals I have are for the PRO and the CL-36, and they don't
have a tri-band reflector.
Does anyone have any insights on this? Reading the archives tells me this
is supposed to be one of the best antennas Mosley ever made and I didn't
see a single complaint. Where should I start in trying to diagnose my
problem?
(On another subject - If anyone has a TA-32 manual, I would appreciate the
reflector dimensions and number of trap coil turns - I'm trying to make a
2-element tribander out of spare Mosley parts).
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