longwire aerial?
 

I am acquiring a Sony icf-7600gr and want to put up a longwire aerial for
it- can some one advise on the specs viz wire length etc. also is it
necessary to run a coxial cable from the aerial to the radio and if so how
does one attach (both ends) ie is the shielding attached to the aerial as
wellas the centre core
tks


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.541 / Virus Database: 335 - Release Date: 2003/11/14

Use anywhere from 30 to 50 feet of wire for your Sony - I've found
that to be an adequate length with my 7600G. The antenna (aerial)
connects to the center conductor of the coax and the ground to
.......... you guessed it - ground. You may wish to check this article
regarding a 'low noise' antenna:
http://www.anarc.org/naswa/badx/ante...e_antenna.html
There is a lot more information to be found at:
http://dxworld.com/dxnews.html#ANT
You can put together a nice antenna system with readily available
material and minimum budget that will bring out the best in your
760GR.

Howard

On Sat, 6 Dec 2003 06:52:17 +0200, "Zoltar"
wrote:

I am acquiring a Sony icf-7600gr and want to put up a longwire aerial for
it- can some one advise on the specs viz wire length etc. also is it
necessary to run a coxial cable from the aerial to the radio and if so how
does one attach (both ends) ie is the shielding attached to the aerial as
wellas the centre core
tks


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.541 / Virus Database: 335 - Release Date: 2003/11/14

Zoltar wrote:

I am acquiring a Sony icf-7600gr and want to put up a longwire aerial for
it- can some one advise on the specs viz wire length etc. also is it
necessary to run a coxial cable from the aerial to the radio and if so how
does one attach (both ends) ie is the shielding attached to the aerial as
wellas the centre core
tks


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.541 / Virus Database: 335 - Release Date: 2003/11/14




The antenna can be made from any type of wire you have handy. The length
wil depend on the room you have but anything over 30 feet or so will help.

There are plans and info at the AMANDX site below. Nithing technical
just simple language for beginners

--
73 and Best of DX
Shawn Axelrod

Visit the AMANDX DX site with info for the new or experienced listener:

http://www.angelfire.com/mb/amandx/index.html

REMEMBER ON A CLEAR DAY YOU CAN HEAR FOREVER

"Zoltar" wrote:
I am acquiring a Sony icf-7600gr and want to put up a longwire aerial for
it- can some one advise on the specs viz wire length etc. also is it
necessary to run a coxial cable from the aerial to the radio and if so how
does one attach (both ends) ie is the shielding attached to the aerial as
wellas the centre core

Does the 7600 have a jack for an external antenna, and if so, what does it
look like?

You don't really have to use coaxial cable. In fact, a random wire (it's not
really a longwire) will not be a good match for coaxial cable unless a
matching transformer is used.

You can run a wire of any random length (25 to 50 feet) from the radio to
any convenient support (tree, pole, etc.) Keep it away from power lines, but
try to get it up high and away from sources of interference such as TVs and
computers. It can be run entirely indoors, but that will probably pick up
more noise and interference.

You may find that a longish wire will pick up so much signal that it will
overload your radio. That won't damage the radio, but will generate intermod
which will adversely affect reception.

If you don't have an external antenna jack, just clip the end of your wire
antenna to the telescoping whip. If signals are too strong, just wrap a
couple of turns of the (insulated) wire around the whip.

The antenna wire can be any convenient gauge that's strong enough
mechanically. It should be insulated anywhere it touches anything.

Some folks use a 9:1 matching transformer with their random wire. When
properly grounded, that type of system can reduce noise pickup. What matters
in shortwave radio reception is not so much signal strength, but signal to
noise ratio!

Art Harris N2AH

I have found Longer is always better for antennas;

I have found a Short co-ax lead -in cuts down Man made moise considerably;
I use the cheap, grey Radio Shack Co-ax

( Whatevers cheap, effective & around . .)


In article , "Arthur Harris"
writes:


"Zoltar" wrote:
I am acquiring a Sony icf-7600gr and want to put up a longwire aerial for
it- can some one advise on the specs viz wire length etc. also is it
necessary to run a coxial cable from the aerial to the radio and if so how
does one attach (both ends) ie is the shielding attached to the aerial as
wellas the centre core

Does the 7600 have a jack for an external antenna, and if so, what does it
look like?

You don't really have to use coaxial cable. In fact, a random wire (it's not
really a longwire) will not be a good match for coaxial cable unless a
matching transformer is used.

You can run a wire of any random length (25 to 50 feet) from the radio to
any convenient support (tree, pole, etc.) Keep it away from power lines, but
try to get it up high and away from sources of interference such as TVs and
computers. It can be run entirely indoors, but that will probably pick up
more noise and interference.

You may find that a longish wire will pick up so much signal that it will
overload your radio. That won't damage the radio, but will generate intermod
which will adversely affect reception.

If you don't have an external antenna jack, just clip the end of your wire
antenna to the telescoping whip. If signals are too strong, just wrap a
couple of turns of the (insulated) wire around the whip.

The antenna wire can be any convenient gauge that's strong enough
mechanically. It should be insulated anywhere it touches anything.

Some folks use a 9:1 matching transformer with their random wire. When
properly grounded, that type of system can reduce noise pickup. What matters
in shortwave radio reception is not so much signal strength, but signal to
noise ratio!

Art Harris N2AH

"Diverd4777" wrote:
I have found Longer is always better for antennas;

True in general. But some portables can't handle that much signal. I think
the original poster is in Europe (based the words "aerial" and "centre").
Europeans seem to have more problems with overload due to the abundance of
nearby transmitters.

I have found a Short co-ax lead -in cuts down Man made moise considerably;
I use the cheap, grey Radio Shack Co-ax

Agree with that!

Art Harris N2AH

Arthur Harris schrieb:

"Diverd4777" wrote:
I have found Longer is always better for antennas;

Until the natural noise floor is higher than the receiver's
sensitivity... Modern receivers can squeeze out even short antennas
pretty well - my AR7030 not only has a switchable +10dB preamp, but also
offers an impedance inverter (whatever that is) intended for telescopic
antennas but also useful for short wires.

True in general. But some portables can't handle that much signal. I think
the original poster is in Europe (based the words "aerial" and "centre").
Europeans seem to have more problems with overload due to the abundance of
nearby transmitters.

In fact, I've even experienced IM products when using the 7600G on the
whip alone. A few meters of extra wire like the AN-71 can be used, but
this has to be done carefully and with some antenna tuning /
preselection device, something also to be recommend when using the radio
on the whip alone (antenna tuning out of the box doesn't seem too great
in some ranges). (If an antenna is connected via a properly inserted
3.5mm plug, the maximum length will be higher since the receiver enables
some kind of attenuation then.) That's not an issue with the AOR, of
course, this should handle even nice big antennas (like, say, a 40 m
Delta Loop) well.

The OP, BTW, obviously seems to be from South Africa. Signal levels
should be a whole lot less critical there (unless one happens to live
next to a xmtr station, that is) - well, of course, everything is less
critical then Central Europe. ;) As always, some experimenting will be
needed to figure out the optimum antenna length.

Stephan
--
Home: http://stephan.win31.de/ | Webm.: http://www.i24.com/
PC#6: i440LX, 2xCel300A, 448 MB, 18 GB, ATI AGP 32 MB, 110W
This is a SCSI-inside, Legacy-plus, TCPA-free computer :)
Reply to newsgroup only. | See home page for working e-mail address.

Zoltar,

Take the Time to READ these two Messages about the
"Portable Wire Antenna" that was created/described
- - - by Tom Sevart [N2UHC].

* Three Ways to Use the "Portable Wire Antenna" (PWA)
http://groups.yahoo.com/group/SWL-AM...na/message/306

* The "PWA" [Portable Wire Antenna]... for use with'portable' radios
http://groups.yahoo.com/group/SWL-AM...na/message/249

iane ~ RHF
..
..
= = = "Zoltar"
= = = wrote in message ...

I am acquiring a Sony icf-7600gr and want to put up a longwire
aerial for it- can some one advise on the specs viz wire length
etc. also is it necessary to run a coxial cable from the aerial
to the radio and if so how does one attach (both ends) ie is the
shielding attached to the aerial as wellas the centre core
tks

..