> II> Of course, there is nothing stopping you from experimenting with
> II> your tassle idea... hey, it might work great! After all, isn't
> II> that what amateur radio is all about?
> JE> Bingo!
> JE> Actually, this idea DOES work - there are some people who have been
> JE> using this antenna in town for around 10 years, now. Just thought
I'd
> JE> toss it out here, to see what kind of reaction I could get.
> Ten years, huh? Ham radio has been around for over a century.
> I find it amazing that this has not been tried long before this!
> It would be interesting to do a side-by-side comparison - two
> identical antennas, one of the two-wire design, the other using
> tassels, in the same location and pointing the same direction:
> Raise one antenna, do field strength measurements under known
> conditions, then lower that antenna and raise the other one to
> the same position and repeat the measurments, then compare the
> readings. (Signal reports at a distance would be unreliable due
> to changing band conditions during the time it takes to lower one
> antenna and raise the other one). IMO, this would be the only
> way to do an accurate comparison.
Agreed.
> I would be very intereted to see such a comparison to see if the
> tassle type is really equal to the 2-wire type or if the resonance
> of the of the longer leg disrupts the resonance of the higher
> frequency portion. Remember, the majority of the radiation
> fro a transmitting antenna is at the highest-voltage point, in
> other words, the unfed end(s). If the ends of the higher-frequency
> section are hanging vertically, I would think that would create lobes off
> the ends of the antenna rather than broadside as in a standard dipole.
> How strong these side lobes are would depend on how long the tassels are.
Let's hope it works out, because I plan on working with this design sometime
this week. I've got a little running around to do in the morning, but plans
are to get my 75m antenna down from the other QTH, where I was, and put it up
here.
I'm convinced that this is going to turn out to be a decent RF area, since I
was heard with favorable reports in Dallas, Houston and other parts of Texas,
this morning. This, on 75m, with a 40m antenna, and the pi-output of the
Hallicrafter HT-37.
> My GUESS would be that the 2-wire type would outperform the
> tassle type by some percentage... possibly a dB or so, possibly
> several dB. Please let me know how your experiments turn out!
Not a problem. As I've said, I plan on starting the antenna construction,
tomorrow.
> JE> Well, right now I'm still working on getting one of my old
> JE> transmitters running again, so I CAN try some antenna
perimentation.
> Please do, and let us know what happens!
Did! Found out that a 2.5milli Henry RF choke had died. Futher operation of
the rig has shown me that there was an intermittent cathode-to-grid short in
the 12BY7A driver tube. Replaced it, strung some other chokes together, and
replaced the 2.5 with those, and I'm back on the air!
Been in touch with Ruthie/AA2IO and her husband, John, sent me some exact
replacements. Good people, the Cunliffe's - I asked for one choke, and got 5
sent here :-)
> If it's successful and equal in performance to the multi-wire
> version, it's a heck of a good idea which should spread like wildfire,
> (especially among people like myself who are limited in both money and
> ability to convince the landlord to allow yet another antenna on the
> property!) ;-}
All you need is the land to run a 75m antenna, Ivy, and try it for yourself.
Let me know how you make out.
> Catch you later es 73 de KB9QPM
you operate CW, Ivy? I've been hanging around 7.040MHz (+/-) and can usually
be heard later on in the evening... or during the night (2, 3am... when it's
COOL around here!)
73 = Best Regards
-Jeff KA5THB
ka5thb@bigfoot.com
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