I've been on internet for 1 week and it's great to see so many
friends on here.
I plan to put up a ZL special aimed south for 40 and 80 meters
and would like to feed them with coax. Has anyone put up one using
coax and a balun ? My existing antennas 2 ele. yagi at 100' on 40 meters
and the 4 square vertical array on 80 meters are too low angle for
the Carribean and central america. I think ZL specials at 50' would
be just right for the distance.
73, Jeff k1iu@ids.net
>From kiddi@marel.is (Kristinn Andersen) Tue Apr 12 19:59:13 1994
From: kiddi@marel.is (Kristinn Andersen) (Kristinn Andersen)
Subject: Suggestions for QRP rigs/kits?
Message-ID: <9404121859.AA04781@marel.is>
Summer is on its way (even up here at the 64th latitude north!) and soon it
will be time for backpacking and field operation. Can anyone suggest a
"good" rig, kit or homebrew HF construction costing within, say, $150-200?
Desirable features (not necessarily a complete wish list):
Around 5W output
Stable VFO
Efficient power usage (RX and TX)
One-bander/Multiband depending on complexity
CW-only will probably be just fine
Compact
Reliable design (dependable specs)
Rugged construction (suited for the glaciers...)
Overall good performance
I could go ahead and just order a kit from one of the radio outlet places,
but I'd prefer some real operating evaluations first. I guess a good source
of information, in addition to you seasoned contesters, may be some of the
QRP associations/clubs around, but I don't have any addresses there.
Anything that
leads to FAST results (say, FAX/phone numbers) would help, in addition to
your own comments.
Please send responses directly to me: "kiddi@marel.is"
and I'll summarize the results on the reflector if it looks like worth it.
Thanks - 73 de Kris, TF3KX
>From H. Ward Silver" <hwardsil@seattleu.edu Tue Apr 12 20:26:59 1994
From: H. Ward Silver" <hwardsil@seattleu.edu (H. Ward Silver)
Subject: Rating System respondees
Message-ID: <Pine.3.07.9404121259.D29273-9100000@bach>
Thanks to all who wrote and requested the full system. Remember, it's the
"gears and levers" and not meant to be particularly easy reading, just a
formal description of how the thing is envivionsed to work. I will
respond to some of your replies after I get back from Visalia where I will
get an earful, no doubt!
73, Ward N0AX
>From Roy Hradilek <73374.2465@CompuServe.COM> Tue Apr 12 21:03:14 1994
From: Roy Hradilek <73374.2465@CompuServe.COM> (Roy Hradilek)
Subject: Who Needs Front-to-Back?
Message-ID: <940412200314_73374.2465_DHS49-1@CompuServe.COM>
I agree with KM9P that front to back optimization for yagis is
not necessary. Here in Texas, I have never had a problem with QRM
from the Pacific while running Europe. Running JA, it is GOOD to
have South Americans answer off the back of the beam, especially
when I need zone 12. The main QRM problem is the unruly East
Coast, which is in the same direction as Europe.
I have been setting the F/B priority of YO to zero for some time.
You optimize only for forward gain and SWR bandwidth. It simpli-
fies things. Any beam with an F/B of better than 30 db gives up
about a full db of forward gain. Even most of DX Engineering's
optimized product line advertises such a high F/B. High forward
gain antennas operate by squeezing signal out of the side lobes,
not off the back. The optimized beam with the highest forward
gain will have the narrowest BEAM WIDTH, and an F/B under 20db
(even as low as 10db).
So who needs front to back? I haven't a clue as to how the bands
sound from the East Coast in a contest, and can't understand why
anyone up there should worry about whether somebody west of the
Mississippi is S9+20 or only S9. They're going to blow us off the
run frequency anyway, right? Such a luxury it must be to have 1,
2 & 3 Land in your skip zone! When 10 or 15 are packed wall-to-
wall on an EU opening, all run frequencies are grabbed before the
sun touches the central time zone. Frequencies near you are
aggressively defended against western riffraff by other East
Coast buddies you may not even hear. And then, Europe is loud
anyway!
So then, does anybody need front to back? Maybe in Western
Europe, with so many dirty QRO signals further east. Perhaps it
is important to ANTENNA MANUFACTURERS. Back before antenna
modelling, all commercial beams advertised flat SWR, high F/B AND
enormous gain - but we couldn't MEASURE the gain! We all have SWR
meters. We can swing the beam back and forth and get F/B measure-
ments from our S-Meter or friends. We can COUNT the elements, and
the new antenna sure beat the heck out of the old trap vertical.
We were happy, but without another beam to compare it to, we
couldn't tell if the antenna had maximum gain. Antenna manufac-
turers were free to make any claims they wanted - and did. We
were impressed by the NUMBER of elements, a flat SWR, a high F/B,
and a high CLAIMED forward gain. This sold antennas. A lot of the
commercial beams that come configured on YO optimize better if
you REMOVE an element and use the same boom (eg: the 205CA). So
then, is Front-to-Back Ratio an important design priority?
Opposing viewpoints are welcome.
de Roy - AD5Q, Houston.
>From Peter G. Smith" <n4zr@netcom.com Tue Apr 12 21:33:28 1994
From: Peter G. Smith" <n4zr@netcom.com (Peter G. Smith)
Subject: Last call for KH6IJ memories
Message-ID: <Pine.3.85.9404121328.A6957-0100000@netcom6>
After an initial flurry of activity, the reminiscences about KH6IJ have
pretty well dried up. If you would like to add to the collection of
messages that will be passed on to Katashi Nose's family, please do so
before the end of this week. Send them to me and I will see that they
are appropriately packaged and passed on to them.
73, Pete
n4zr@netcom.com
NOTE: New Address
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