[SMCARA] 20m Beam Project

[Daniel Metcalf]

It is a little floppy but it seems to work. I'm not sure if it's floppiness
is helping or hurting me at this point.
On Aug 12, 2011 9:27 AM, "Clarke, Tom AIR4.0P NATOPS" <
frederic.clarke at navy.mil> wrote:
> Congratulations Dan!
>
> Ham Radio at its best. Playing with antennas is a fun exercise and you
> can really see the results immediately, Good or Bad!!
>
> You say you used all PVC. I take it you did not use wooden dowels for
> the elements and I wonder how "floppy" it is? I tried making an antenna
> (homemade Buddipole) a while ago with PVC and wound up putting dowels
> inside the PVC to "stiffen" it up. That sort of defeated the
> lightweight aspect of using PVC though.
>
> Measuring front to back ratio pretty much requires an antenna test
> range, but you can get a relative idea by tuning in a strong steady
> carrier and then peaking with the antenna pointed toward and away from
> the signal source with the beam. The S meter will give you an idea of
> the f/b ratio. If you really wanted to be fancy, you could take a
> reading every 15 degrees or so and plot it on a circular chart. That
> would also give you an idea of where the nulls are. I suppose that you
> could also model it with NEC, but getting the real data is more fun!
> Relative is the operative word here, but you still will have some
> bragging rights!
>
> 73 Tom/W4OKW
>
> -----Original Message-----
> From: smcara-bounces at mailman.qth.net
> [mailto:smcara-bounces at mailman.qth.net] On Behalf Of Daniel Metcalf
> Sent: Friday, August 12, 2011 9:01 AM
> To: smcara at mailman.qth.net
> Subject: [SMCARA] 20m Beam Project
>
> Good Morning All,
>
> I just finished building a two element beam antenna
> (http://uts.cc.utexas.edu/~hansongr/Miniyagi.htm but all PVC) last
> night and so far the results are looking good. Using my FT-897's SWR
> meter and being without a tuner I am showing an SWR of 1.3:1 down at
> 14.175, SWR of 1.1:1 at 14.250 and SWR of 1.2:1 up at 14.325. Without
> having to trim anything once it was up it was up (I am either really
> good at this or extremely lucky Hi Hi).
>
> Using only 75 watts I made 2 contacts with it last night W4PSC in
> florida but being he was off to the side of the beam (which is
> pointing West to North West and pointing it via arm strong method) I
> lost him after exchanging call signs. Then came WA0UAY Rick from Iowa
> who monitored the signal throughout the conversation about the antenna
> periodically reported 58 to 59. I think he is going to build one now.
>
> If I had the patience to wait I would have liked to of answered to the
> two gentlemen from Los Angeles on 14.240 and 14.245 last night as I
> had them 59++ on the meter but they were busy dealing with their pile
> ups. Hope to get more data tonight.
>
> One thing Rick WA0UAY was interested in was the front to back ratio.
> How does one go about figuring that out?
>
>
> 73's
> Dan -- KB3UUN
> ______________________________________________________________
> SMCARA mailing list
> Home: http://mailman.qth.net/mailman/listinfo/smcara
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:SMCARA at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> ______________________________________________________________
> SMCARA mailing list
> Home: http://mailman.qth.net/mailman/listinfo/smcara
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:SMCARA at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html