Today I started experimenting with listening antennas. My goal is to find something I can pack in my truck and set up deep in the heart of baja for weather nets. My first purchase was an ANLP1 active antenna and that works great because right now I'm using a G5 portable radio which like the ANLP1 has a mini Jack connector. However I'm making a big upgrade in the radio departmnet (probably a aor7030) so I wanted to start testing against the ANLP1 to get some antenna intel and a random wire was the obvious first step. At first glance the random wire seems to work a little better than the ANLP1. At times the wire seems to pull in more signal and at times it's almost exactly the same. The wire is 100 feet long and hanging about 30 feet up. The ANLP1 is about 20 feet up. So I have some questions for all you folks who know lots about this stuff. Thanks for any info you can share.

Is this a suprising result? I kinda thought the active antenna would outperform the wire.

Will a tuned mutliband really be that much better?

If you were going to make an antenna that's relatively easy to store and set up with the goal of getting some
fun radio stations and a handfull of sideband stations what would you opt for? I would define easy as raising a 30ft guyed mast as relatively easy. A 140 foot multiband wire antenna off that would be pushing the limits if not too much space.

And finally, will the reception of the ANLP1 increase very much if it's 30 feet up?

Thanks for your time helping out a rookie. I'm slowly being sucked in!

On Sun, 7 Nov 2010 01:46:03 +0000, Bajamatic
wrote:

Is this a suprising result? I kinda thought the active antenna would
outperform the wire.

You don't tell enough specifics to judge your experience. Frequency,
time of day, antenna orientation all play significant factors.

However, as you are going into a desert location (or at least a very
much less populated area), you are going to have less noise to contend
with, and less interfering signals (out of band signals like AM
stations can seriously de-sensitize your receiver). All this bodes
well for a simple wire antenna (and not necessarily goliath 100
footers). Any additional equipment would be an antenna tuner (a very
cheap version of what Ham radio operators use for transmitters - so
you won't need those power/SWR meters) and some form of ground - if
only another wire trailing along the ground.

73's
Richard Clark, KB7QHC

On Nov 6, 7:46*pm, Bajamatic
wrote:


Is this a suprising result? *I kinda thought the active antenna would
outperform the wire.

Sounds normal to me. The loop on the active antenna is
very small. Not a heck of a lot for the preamp to work with.


Will a tuned mutliband really be that much better?

Not if you are just receiving.

If you were going to make an antenna that's relatively easy to store and
set up with the goal of getting some
fun radio stations and a handfull of sideband stations what would you
opt for?

I use dipoles fed parallel from coax. But I transmit..

*I would define easy as raising a 30ft guyed mast as relatively
easy. A 140 foot multiband wire antenna off that would be pushing the
limits if not too much space.


Would be overkill for receiving.

And finally, will the reception of the ANLP1 increase very much if it's
30 feet up?

Not for most signals. Only if they were line of sight.


Thanks for your time helping out a rookie. *I'm slowly being sucked in!

--
Bajamatic

If you are receiving, you really don't even need a feedline for
random wire antennas. So I'd just take a roll of wire and throw it
up to match the site. Heck, take both of them if you have the
room. But if I had to choose one, I'd take the wire.
Even 50 feet should be plenty. And it doesn't have to be high
off the ground either.

I camp quite a bit, and have often transmitted with dipoles as low
as five or so feet off the ground when I had no trees or tall
supports.

I've got a place out in the sticks, and I always have a radio there,
but I have dipoles in the trees that I leave there. I run 80 and 40
dipoles on a single coax and the apex is up in an oak tree about
25 feet or so. I've got about 100 feet of RG-58, so it will pretty
reach
anywhere around the camp or driveway area. I usually stick the radio
on a stone bench I have there and power it off the car.
When I leave, I roll up the coax and hang it on a tree branch stump.
This was about three weekends ago.. Weather net on 75m I
stumbled across.. Scuse the camera focus hunting.. :/
http://home.comcast.net/~disk100/radio.wmv

BTW.. the antenna is resonant 80/40, but I have no trouble
receiving any other HF frequency. When I was there three weeks
ago, all bands were open up to 10 meters and I had no trouble
hearing any of them. Receiving is just not very critical.
It even does OK on VHF.. I listen to the local sheriff dept, etc
at night sometimes. I have no trouble hearing them on that HF
antenna.
I've got to where I use the radio more out there in the sticks
than I do here at home.. :/

On Sun, 7 Nov 2010 07:29, wrote:
On Nov 6, 7:46*pm, Bajamatic wrote:

And finally, will the reception of the ANLP1 increase very much if
it's 30 feet up?

Not for most signals. Only if they were line of sight.

Well, it _might_ get the device up and away from local _noise_ sources.

On Nov 7, 1:03*pm, Allodoxaphobia
wrote:
On Sun, 7 Nov 2010 07:29, wrote:
On Nov 6, 7:46 pm, Bajamatic wrote:

And finally, will the reception of the ANLP1 increase very much if
it's 30 feet up?

Not for most signals. Only if they were line of sight.

Well, it _might_ get the device up and away from local _noise_ sources.

If he's out in the sticks, there should be no local noise sources.
That's one reason why he really doesn't need to even use a
feed line per say. Local noise should not be an issue.
And if there were any power line noise from the general area,
elevating the antenna will just increase it if it's line of sight.
For sky wave signals, elevating that small loop is not
worth the trouble out in the Baja which I assume is a semi-
desert type terrain. It should do almost as well low as it
does elevated.
As long as the signals are not local line of sight, even the wire
antenna doesn't need to be too high. Five feet off the ground
will work just fine for most HF reception that is sky wave.
With a decent length wire, you will still have more signal
than is required for any decent radio. And almost anything
made these days is fairly sensitive. Even the cheap portables.

Thanks for all this info. As i'm still just listening, I think I'm starting to understand that all the tuning and matching is somewhat irrelevant to my needs. There is literally nothing for miles where I'll be deploying this and all I really care about is catching the morning weather round up around 7250 kHz and then whatever else I can pick up while sitting fireside. So far the random wire seems like the cheapest and easiest way to go, and maybe even the best all around performer. I figure I'll get a spool of wire and run it at least 4 feet off the ground - is that really all I need to do?! Since thats so easy, I'll probably play with a SUPER long one (500 feet+), and then find the best balance between performance length and convenience. Two more questions before I put it to test:

will if effect the performance if the antenna comes into contact with the ground?

Will I get the same results if I make a 20 foot x 20 foot square and run a huge length of wire along the perimeter at different heights so as not to short but essentially 500 feet of wire run around a shape instead of in a relatively straight line?


Thanks for all your insight.

bmtc

On Mon, 8 Nov 2010 18:44:04 +0000, Bajamatic
wrote:

I'll
probably play with a SUPER long one (500 feet+), and then find the best
balance between performance length and convenience.

Take care to anticipate that this long an antenna may well have to
pointed at (lengthwise) the station you want to receive instead of
pointed broadside to it.

Two more questions
before I put it to test:

will if effect the performance if the antenna comes into contact with
the ground?

Yes - more loss. However, the troops in Desert Storm did it in the
sand dunes; but they were only talking to local operations - not DXing
Andorra.

Will I get the same results if I make a 20 foot x 20 foot square and run
a huge length of wire along the perimeter at different heights so as not
to short but essentially 500 feet of wire run around a shape instead of
in a relatively straight line?

500 feet of wire is not a virture.

73's
Richard Clark, KB7QHC

. Thanks for the advice.

While out and about beware of your DC-AC inverter if you have one. If
hear whistles and hum, it might come from your own DC-AC inverter.
All my AC stuff (PC, cell chargers) is strictly inside the car, so
not much noise escapes and even longwave is clear and quiet (I am in
Europe). If you have that problem, move antenna and other electric
stuff away from each other.

The AOR7030 has a high impedance wire antenna input. If you're
really fireside, not easy to beat a random wire, and not even a
terribly long one. I wouldn't bother with more than 30-50'.

Just don't trip in the power cord under the moonlight. That radio
needs external power, 12Vdc from a vehicle is fine.

You'll have great fun, I envy you a bit.

On Tue, 9 Nov 2010 08:44:21 -0800 (PST), spamhog
wrote:

The AOR7030 has a high impedance wire antenna input. If you're
really fireside, not easy to beat a random wire, and not even a
terribly long one. I wouldn't bother with more than 30-50'.

To give some context with my own experience "in the wild" of South
Africa Zulu/Natal (actually at a 5 star safari camp), I took the
cheapest digital SW radio I could find at Radio Shack, 20 feet of
wire-wrap wire, and connected an alligator clip to the wire so that I
could then connect the wire to the whip antenna.

Without the wire, reception was limited to the hum-drum of BBC, VOA,
DW - with the wire thrown up over a rafter the number of signals were
considerable. I've always considered it underwhelming to get a
distant station playing an American music program like Lady Gaga when
what I wanted to hear was Fela Kuti.

73's
Richard Clark, KB7QHC