In a message dated 2/22/03 8:02:40 AM Pacific Standard Time, W1JR@arrl.net
writes:
> HI Dave,
>
> Yes, when the capacity hats fall off, so does F/B and gain! You'll
probably
> find that the 36" element broke due to vibration and that the so called
> 2-meter Yagi clamp is still in place. If not, let me know and I can
arrange
> to send you one.
>
> As for 17 meters, the 40-2CD has a resonance at about 19 MHz so it has a
> few dB F/B and some gain. I worked about 200 DXCC with mine before I
> designed the A3WS and put it up for WARC. On 12 meters, I don't know.
>
> The 40-2CD is a great performer. One of those flukes that come along every
> so often. I miss mine! I hope to out up an XM-240 soon.
>
> 73,
>
> Joe, W1JR
>
>
> At 09:52 AM 2/22/2003 -0500, you wrote:
> >The Cushcraft design appears very similar to the 3 el 40 short beam from
> the
> >ARRL Antenna Book circa 1980. It was 3 elements on a 36 foot boom with
the
> >reflector and driven element spaced 23 feet. It used coils with a
capacity
> >hat on each element half. I think maybe it was Joe W1JR that told me in
> >about 1984 that converting to a 3 el was not really worth the effort. I
> >remember the figure of .8Db more forward gain and a sharper pattern.
> >
> >I did lose one of the capacity hats on one reflector element half. At
> first
> >I noticed that the SWR
> >changed from mid band (7180 or so) to 7230 but little change in results.
> >The past few months
> >I now find the beam has lost front to back with beaming NW/SE its better
> off
> >the back by sometimes an S unit. Europe and VL/ZL are about equal
strength
> >either was. I can keep the beam between NW and ENE and work about
anything.
>
> >However I plan on replacing the hat. I have the actual pieces of metal
for
> >the har. Just not sure if the clamp is still there (hard to see 87 feet
> >up). Ed K4SB says its a 2 meter element to boom clamp. Gotta crank down
> >all the amtennas. Health problems have kept me from doing the work until
> >now.
> >
> >I previously used a Mosley 2 el S-402 (the Cushcraft is much better) and a
> >Create 3 el HB9CV
> >on a 36 foot boom. Too flimsy and aluminum windings arced at over 1KW.
> >Seemed to work as well as the Cushcraft. The Cushcraft was compared to a
> >Telrex 3 el 40 on a 29 foot boom at N4RJ and was at least as good every
> time
> >(I would win 50% of the time). Val N4RJ then switched to a 3 el on a 46
> >foot boom and now he beat me at least 50% of the time.
> >
> >A number of people told me my beam was a killer and bought their own beam.
> >K1MM told me his worked well on 17 and 12. I found the beam works very
> well
> >on 17 but on 12 its a cloverleaf pattern so its either boom or bust (S9+
in
> >JA and S3 in DU). The beam works on 160 too! It loads thru a tuner but
> >having the remote coax switch in line forces me to run 100 watts max. My
> >firsdt contact on 160 using the beam was HC8DX on SSB in 1987. I got a
> >59+20 and he had me confused with K4JPD. That was before I ran the remote
> >switch. I still use it on receive and the last couple of years used in
> >during the CQ 160 SSB.
> >
> >I have not checked out the coil Q (so so according to W1JR). However it
> >makes a great 40 antenna for the little/medium gun!
> >73 Dave K4JRB
> >
> >
> >73 Dave K4JRB
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