Posted by
Mark J. Schreiner on
Dec 07, 2005; 5:17am
URL: http://elecraft.85.s1.nabble.com/ARRL-160-Rx-antenna-tp384360p384361.html
Bill and others,
The explanations by Don & Ron were as always right on and very helpful.
I already knew the answers but enjoyed reading the replies anyway. I
still have questions, though, too, so please continue to read on (we get
there eventually).
I would like to point out a couple of resources for more info on the
topic. First is a book by John Devoldere, ON4UN called "80m DXing",
oops, sorry, I'm showing my age, it is now called "Low Band DXing" or
"Antennas and Techniques on Low Band DXing". I did a quick Google
search and guess I should pick up a more up to date version of the
book. The copy I have is from 1978 and was an excellent resource at
that time. Recently looking through it some info is obviously dated
(comparison of different radios now considered to be "vintage" although
still excellent rigs even compared to today's newer radios, such as the
Drake R4B/C, Kenwood TS820, Collins S-Line/KWM2, Signal One CX7,
Collins R390, Heath SB101, etc) while other information is timeless
(theoretical and practical info on the antennas for the most part as
well as operating practices). It gives lots of great info on these
subjects with practical examples from a time honored expert.
Another book that is about 10 years newer for the copy I have which is a
2nd edition, although it looks like the latest release that is still
available is the 3rd edition, but I'm not sure when it came out, is
called "The Beverage Antenna Handbook" by Victor Misek, W1WCR. This
book includes topics on single wire Travelling Wave Antennas & multiple
wire Steerable Wave Antennas. As is the case for most ham related books
it is mostly practical and only moderately theoretical.
Both of the above examples require a bit of real estate, or at least a
cooperative neighbor. I convinced my neighbor at one time that the wire
I proposed to run out onto his property was only used for Rx and I
guaranteed to him that *it* would not cause interference. This
negotiation worked and my neighbor and I still have a good relationship
to this day (long after I've moved away, although my moving away is not
the reason for our good relationship these days!). I've seen other
installations that have also taken advantage of a "good neighbor
policy". Try it, it works!
Other Rx antennas that are popular lately and work almost as well
without nearly as much real estate which you should be able to find more
info on the web include the EWE Array or K9AY loops. I'm currently
investigating the latter along with a small magnetic loop (oh, I thought
it was small for 160m at about 12' diameter, maybe I should make it
smaller yet!).
Okay, now for the questions that I have. Having recently worked several
stations surprisingly easily with my K2 at 5W during the recent Top Band
contests (both the ARRL as well as the less active QRP ARCI a few days
before) I am intrigued with possibilities of a Rx Only antenna. I know
the old saying that "You gotta hear 'em before you can work 'em" surely
applies, however, I think that especially when running QRP the station
on the other end has much more work to be able to hear your signal, so
they need to likely have an even better Rx station than you have. There
were several stations which I couldn't work that had moderate (not
strong and not weak) signals during this past weekend. Maybe if they
had better Rx antennas I could have worked them. I tried several
different times hoping that conditions maybe had improved. Generally
this was on Friday night while at my QTH Saturday night didn't seem as
good. However, my questions (finally) are these: If I have a great Rx
only antenna won't I be able to hear many more stations that I probably
won't be able to work? Okay, so there is a possibility that some of
those stations will also have great Rx antennas and so between the two
of us we may be able to work where previously I may not have been able
to hear (and hence work) them. But does anyone have any experience with
this and care to comment? I'm not trying to gather this information to
discourage the attemps, just looking for some practical experience on
this as part of a "reality check". I have only so far worked one
European station and heard very few on 160m, but my experiences on 160m
with the K2 are just beginning. The guy I worked in Greece was using a
1000' Beverage for the USA (one and the longest of 4 that he had total)
and I think was running about 800W. With my Carolina Windom at about
45' that I used on both Tx & Rx I was barely able to copy him initially,
then as his signal finally improved so that I could copy so-so, good
enough to copy his callsign after enough times of him calling CQ or a
few people now and again answering him (while there was several big
pileups a few kHz above). Finally when I was sure of his call I called
him and he came back and fairly quickly the QSO was in the logbook! I
remember giving him a 559, which was really a bit of a stretch, but he
gave me a 569 even though I was running only 5W compared to his 800W.
Okay, so with enough stations out there with serious Rx antennas I'll
likely be able to work a few more, if only I can hear them as well, I
suppose, but I'm still anxious to hear any practical experience in this
activity.
I'd also like to add that my most memorable DXing on 160m was while I
was a kid in Michigan (maybe 1983 timeframe) and using an antenna that
shouldn't have worked and today with my experience I would likely not
ever attempt to use it. However, I didn't know better at the time and
used it anyway. It was about a 15 to 20' vertical with a large loading
coil about 2/3 of the way up. Not sure where this was supposed to work
but I put it on a homebrew tripod sitting on a 2nd floor porch and ran a
single #8 or #10 ground wire (Aluminum from RatShack) to a copper ground
rod made of 4 to 6' of 3/4" copper pipe. With my TS820S at 100W I heard
a large pileup for the Marshall Islands. Rather than bumping heads with
guys running "real" antennas and probably most running much more than
100W I tuned around a bit figuring that the band should be open to that
area in general so maybe I'd find another station with less of a
pileup. Sure enough, I found KH6VT on Hawaii and quickly worked him.
Moments later I found a station I had no idea where he was located, but
there was this voice in the back of my head from my Elmer, K8OT, who
told me "Work 'em first, worry about 'em later" so I worked UV1OO. I
then reallized it was Franz Josef Land (look it up if you don't know
where it is, I didn't originally! Hint, it is in the Barents Sea east
of Svalbard and north of mainland Russia). Wow, what awesome
conditions, and working them back to back in different directions with
an antenna that wasn't supposed to work! I shut off the rig and went to
bed with happy thoughts rather than risking an attempt to work yet
another DX station and possibly not getting through. Boy, times have
changed as I would take that risk today if I heard such great band
conditions while using an antenna that "should" work and my trusty K2
running QRP.
Sorry for the *really* long email. Just wanted to offer some
encouragement & possibilities for one of my favorite bands (especially
now near the bottom of the solar cycle). CU on 160m!
Mark, NK8Q
K2 4786
[hidden email] wrote:
>
>Julius,
>
>Would you (or anyone) please elaborate on the use of an Rx antenna?
>
>Thanks
>Bill K3UJ
>
>
>
>
>
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