On Wed, 19 Jul 2006 11:48:47 -0500, "hasan schiers"
wrote:

So...what should I do:
2. Add 20 radials, maintaining my 50' length that I originally used.

Hi Hasan,

Build for the future. Anticipate working 160M. Enjoy the advantages
(as slim as they may be) at 80M.

73's
Richard Clark, KB7QHC

Good thinking, Richard, as I may try to get this inverted L to do 160 in the
fall/winter by adding a trap to the 80m inverted L and extending the wire
for 160m resonance.

Incidentally, over the weekend I tried to add a 40m wire parallel to the 80m
L...it was a complete failure. (I used a "fan" approach with 6" standoffs
for the 33' vertical wire). I thought I might get 2 fer 1 at the feedpoint,
but it just didn't work worth a darn. Very low noise level, signals were
significantly weaker than my Carolina Windom 80 (on 40m) up 42'. I did work
a few DX stations with it, but just not up to my expectations. A properly
performing 40m 1/4 w vertical over very good soil and a full radial field as
described in my prior message should have been outstanding. It wasn't. It
was very hard to tune, showed no better than a 3:1 VSWR at resonance, and
was only marginally better on a very few signals between sunset and sunrise.
Very disappointing.

So...your suggestion for 160m is a good one. I could do a trap pretty
easily. If I wanted to try 40m with the same feedpoint, I could put a
parallel tuned circuit at the feedpoint and run the 80m inverted L as a 40m
half-wave. Of course, this requires switching at the feedpoint and I'm not
sure I'd bother. I also have to get a 1.9 uH coil and 250 pf variable cap to
do the tuned circuit (per ON4UN's Low Band DXing Handbook). I found an
acceptable cap for 40 bucks and coil stock is readily available. I just have
to get motivated and work out the relay switching.

I wondered if I could EVALUATE the effectiveness of the 80m inverted L on
40m as a half wave, by temporarily taking an antenna tuner with wide range
(T-network matches almost anything) out to the feedpoint and matching it
there. If it hears well, and works ok at 300w (tuner limit), then it might
be worth investing in the coil/cap/relays to switch a more standard high-Z
feed in and out. What do you think?

Thanks for your input.

73,
....hasan, N0AN
"Richard Clark" wrote in message
...
On Wed, 19 Jul 2006 11:48:47 -0500, "hasan schiers"
wrote:

So...what should I do:
2. Add 20 radials, maintaining my 50' length that I originally used.

Hi Hasan,

Build for the future. Anticipate working 160M. Enjoy the advantages
(as slim as they may be) at 80M.

73's
Richard Clark, KB7QHC

hasan schiers wrote:

I wondered if I could EVALUATE the effectiveness of the 80m inverted L
on 40m as a half wave, by temporarily taking an antenna tuner with wide
range (T-network matches almost anything) out to the feedpoint and
matching it there. If it hears well, and works ok at 300w (tuner
limit), then it might be worth investing in the coil/cap/relays to
switch a more standard high-Z feed in and out. What do you think?

The configuration of 35ft vertical + 35ft (or so) horizontal worked well
for me on 40m at the old QTH, and was quite effective on 80m DX. For
160m, I added a 100ft loading wire to bring the total length up to about
130ft, and that configuration doubled as an end-fed half-wave for 80m
short-skip.

Having a QRO auto-ATU made band changing easy, so it wasn't necessary to
resonate the antenna on any band. However, the quarter-wave resonances
on 80m and 160m could have been trimmed to length.

Coming back to the difference between the 40m vertical quarter-wave and
the bent half-wave, I compared the bare 35ft mast and the same mast with
the added loading wire and didn't find much difference. For DX, the
bent-half-wave should have been down on the quarter-wave (because some
of the radiation was being wasted at high angles); but in contests, both
antennas seemed to work the same regular DX stations. The bent half-wave
was louder for short-skip, which meant more QRM at night, but made it
easier to continue making low-point contacts during daylight hours.

If you use an 80m trap, the antenna could still work on 40m but the
horizontal section would be way over-long. Unless rapid band changing
between 80m and 160m is a priority, I'd suggest you use a physical
disconnect at the end of the 35ft horizontal section. (My setup made it
very easy to loosen a rope and lower the connection into reach, so I
used simple banana plugs, with snap links to add either wire or plain
cord.)




--
73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek

On Wed, 19 Jul 2006 13:03:16 -0500, "hasan schiers"
wrote:
Incidentally, over the weekend I tried to add a 40m wire parallel to the 80m
L...it was a complete failure. (I used a "fan" approach with 6" standoffs
for the 33' vertical wire). I thought I might get 2 fer 1 at the feedpoint,
but it just didn't work worth a darn.

Hi Hasan,

I must think that you were only slightly off in length, and that the
proximity, even at 6 inches, is still proximal.

Very low noise level, signals were
significantly weaker than my Carolina Windom 80 (on 40m) up 42'.

Not unlike many similar reports.

I did work
a few DX stations with it, but just not up to my expectations. A properly
performing 40m 1/4 w vertical over very good soil and a full radial field as
described in my prior message should have been outstanding. It wasn't.

Some of those same reporters suggest split operation where the
vertical is the radiator and a high horizontal is the receiving
antenna.

I wondered if I could EVALUATE the effectiveness of the 80m inverted L on
40m as a half wave, by temporarily taking an antenna tuner with wide range
(T-network matches almost anything) out to the feedpoint and matching it
there. If it hears well, and works ok at 300w (tuner limit), then it might
be worth investing in the coil/cap/relays to switch a more standard high-Z
feed in and out. What do you think?

I would encourage that, simply because you seem to be amenable to such
a path already. Gaining experience is always a noble work.

73's
Richard Clark, KB7QHC