Windom OR Alpha Delta
Wayne Eads
Does anyone know if the alpha delta dx-cc or dx-lb plus are good multi
band antennas? Am considering these, and the radio works carolina windom
80. I just have 110 feet of space, and would let a few feet on each end of
the windom hang free. Which of these would be the best choice, or other?
Thanks. Wayne Eads KD5EDC
we...@brightok.net
Phil Wheeler
Gary Coffman wrote:
>
>
> What I'm trying to tell you here is that wire is wire. Get it as high as you
> can, feed it in the center, and operate. It'll work just as well as wire you
> pay too much for.
>
> Gary
> Gary Coffman KE4ZV | You make it |mail to ke...@bellsouth.net
> 534 Shannon Way | We break it |
> Lawrenceville, GA | Guaranteed |
Jeez, Gary. First you tell him to make it, then you guaranty you will
break it <Grin!>
Right on advice re wire being wire!
Phil
Gary Coffman
I don't want this to come off as a putdown, Wayne, but the best price on
wire is at your local electrical supply house. Why would you pay someone
else more for it? If you're paying more than 10 cents a foot, you're paying
too much.
I assume you have a yardstick, or other measuring device already. If not,
your arms outstretched at shoulder level span about 6 feet if you are of
average size. That's a good enough measuring method to get you in the
ballpark. Since you only have a 110 foot span, that fixes the dimension
of your antenna anyway. Run it the full available span, cut it in the center
(I assume you do own a pair of dikes?), and insert an insulator there
(a piece of wood that has been boiled in parafin will do if you have nothing
better at hand). Attach your balanced feeder there and run it down to the
tuner in the shack. You're done. Have fun on the bands.
W6RCA
Wayne Eads wrote:
>
> Does anyone know if the alpha delta dx-cc or dx-lb plus are good multi
> band antennas? Am considering these, and the radio works carolina windom
> 80. I just have 110 feet of space, and would let a few feet on each end of
> the windom hang free. Which of these would be the best choice, or other?
> Thanks. Wayne Eads KD5EDC
Hi Wayne, before you spend big bucks for an all-HF-band antenna, take a
look at my $25 all-HF-band antenna on my web page. I presently have that
antenna at the 102ft horizontal length with 14ft hanging down on each end
which would be perfect for your location. In addition, if you vary the
length of the feedline, you don't even need an antenna tuner.
--
73, Cecil, W6RCA http://people.delphi.com/CecilMoore
hasan schiers
OK Cecil, lots of us are "sold" big time on your antenna. You are now retired.
So how 'bout getting your line selector project out for us, to include sources
for relays able to tolerate at least 500w.
We want to build!!! Come on now, you promised....as soon as you retired. We are
expecting a silk-screened board, parts list and sources, ...ya know..the whole
shootin' match.
(This is well intentioned needling, folks ...I'm not trying to give Cecil a hard
time.)
I have drooled over Cecil's design since first visiting his web page and then
modelling the performance with EZnec. It is a sure winner, IF and WHEN we get
the line selection job down to realisitic proportions and relays rated for
significant power.
Cecil's proposed auto-selector and yet to be published source for relays is
going to take this newsgroup by storm. He should really consider selling the
selector as a kit and then we can buy the wire, insulators, ladder line and
choke for ourselves. The auto-selector/relay system is just what the doctor
ordered for so many antenna situations. I cannot believe someone has not picked
up on this and marketed the product.
The only thing Cecil's antenna lacks is "convenience", i.e., it requires
switching in/out line sections. Other than that, it is a terrific idea, and
Cecil appears well on his way to solving that issue...just not far enough for
those of us waiting! 73 Cecil and thanks for your efforts.
W6RCA wrote:
--
hasan, N0AN
W6RCA
hasan schiers wrote:
> OK Cecil, lots of us are "sold" big time on your antenna. You are now retired.
> So how 'bout getting your line selector project out for us, to include sources
> for relays able to tolerate at least 500w.
Hi Hasan, My parents in Texas are in pretty bad shape because they have a
son old enough to retire. :-) I am buying a house in my home town in Texas
and selling my house in Arizona so my next couple of months are already
planned. Once I'm settled in Texas, I intend to publish a lot of stuff.
The basic idea is on my web page. Hopefully, everyone can see how to
switch 16/8/4/2/1 ft lengths of ladder-line in and out with ten DPDT
relays. My present auto-switching system is based on my IC-745 which
tells the microcontroller which band it is on so I need to modify the
system to make it universally applicable.
I picked up a dozen P&B relays for $3 each at a surplus store in Silicon
Valley. Almost every big city has such a surplus place. Silicon Valley
has four or five. The relays are KUP-11D15-24 rated at 3amps at 600VAC
(60Hz of course). I intend to use them to switch loops in a 500 watt
system. Somebody more knowledgable than I might contribute an opinion
if that relay will handle 500 watts RF or not. I have a few MRll's which
would be better but I don't have ten of them.
To minimize the impedance bump caused by the relays, I drill two holes
in the plastic cover and bring the center-tap wires out the holes. I
also bend the contacts to get a wider gap. A 16ft loop is only a coil
of radius 2.5 ft. I have my relay/loop assembly fastened to the ceiling
of my patio out of the occasional rain that we have here in Arizona.
If you want to get started, wire up your 16/8/4/2/1 ft loops to ten relays
and simply drive them remotely with five switches. That's what I did
while I was developing the microcontroller system. I had a chart on
the wall that told me what switch positions to use for what frequencies.
It is really not a big deal to throw one to five switches every 50KHz
or so. It is easier than tuning a manual antenna tuner. But I realize
this is the age of automation and will solve that problem probably
by about August.
So Hasan, exactly what is stopping you from setting up my antenna
using 5 switches to drive the 10 relays? After that it will be
easy to wire in the microcontroller autotuner part.
--
73, Cecil, W6RCA
hasan schiers
W6RCA wrote:
>
>
> So Hasan, exactly what is stopping you from setting up my antenna
> using 5 switches to drive the 10 relays? After that it will be
> easy to wire in the microcontroller autotuner part.
> --
> 73, Cecil, W6RCA
Hi Cecil, thanks for the info. As soon as I can get the relays, nothing will stop me
(I hope). I just needed a source for the relays and you gave me one (I think there
is enough detail there to get a phone call done, if not, I'll let ya know.
Now let me give you a real dummy question. (I'll have to go back to your site to see
..), but I thought there were only five relays. Are you using 10 to get enough poles
to switch everything or are you putting relays in parallel to get more power
handling?
Anywho, I'm going to follow up...this project is just too good to pass up. Thanks
again. 73
--
hasan, N0AN
W6RCA
hasan schiers wrote:
> Hi Cecil, thanks for the info. As soon as I can get the relays, nothing will stop me
> (I hope). I just needed a source for the relays and you gave me one (I think there
> is enough detail there to get a phone call done, if not, I'll let ya know.
KUP relays will handle 500w RF. I bent the NC contact away from the NO contact to
increase the air gap. I also brought the C (center-tap) wires straight out through
holes in the plastic cover to avoid the coil being in between the two wires. I did
all that I know to do to adapt these 60Hz relays for RF operation. I sure do wish
that we could go out and buy a 450 ohm DPDT RF relay.
> Now let me give you a real dummy question. (I'll have to go back to your site to see
> ..), but I thought there were only five relays. Are you using 10 to get enough poles
> to switch everything or are you putting relays in parallel to get more power
> handling?
I'm using 2 DPDT relays per loop instead of one 4PDT relay per loop for 2 reasons.
1. The KUP-11D15-24 relays were available surplus for $3 each. :-) I couldn't
find enough surplus 4PDT relays. If you can find MR-11's, they would be ideal
but they went out of production in the early 80's.
2. The spacing between the poles in the DPDT relay is about 3/4 inch while
the spacing between the poles in the 4PDT relay is about 1/8 inch so the
DPDT is more compatible with 450 ohm ladder-line.
Since I retired, I'm having trouble transferring files to my web site or
else I would just publish a few pictures of my setup. Anybody know of a
telnet/file transfer program? The Windows 95 built-in telnet application
will not transfer files and I have telnet-only access to my web page.
--
Good Luck and 73, Cecil, W6RCA
W6RCA
W6RCA wrote:
> Hi Hasan, try the design out at 100w before you apply 500w.
Also, never change the relays with 500w applied. Always tune up
with 100w or less or better yet, use an impedance meter. Once the
antenna system is properly tuned, then switch in the amp.
--
73, Cecil, W6RCA