I have a fifty foot long extension cord here.(yeah,I have some other
extension cords here too) I once draped it around the rooms in my
house,used it for a shortwave radio antenna,it did quite well too,I
might add) That extension cord broke in two just from the age of
it.Nothing beats solid steel non stranded wire for shortwave antennas.Or
good old Barbed Wire.
cuhulin

Lenny wrote:
I've had my Antenna Supermarket Eavesdropper Dipole up for about 4 years
now.
Lately, it seems that reception isn't what it used to be.
Could it be the antenna and coax?
Or is it more likely that reception conditions are lousy?
If you think it is the antenna, could you please suggest a replacement
antenna and high grade coax system for me?
Please keep it simple, I really don't want to get into all the theory and I
don't have a lot of time to research and construct an antenna.
Thanks all.
Lenny




I had an Eavesdropper up for nearly 15 years, with no real signs of
aging. And no deterioration in performance up to the point I took it
down to move it, and then found that I really don't need it with my
other antennae in place.

I have replaced the coax more than once, in that time, however. The
jacket cracked. Moisture gets into the coax and performance drops
precipitously.

Check your traps for signs of leakage. Not likely, but possible.
Especially in direct sunlight, and with large swings in temperature.

Check your connectors for signs of corrosion. Corroded connectors
will be a source of ground irregularities and mismatches. Higher noise.
And if the inner contact is corroded, reduced signal. But if the
connectors are corroded, you're almost always going to have moisture in
the coax. Replace it. With a coax of UV resistant jacket.

When you reinstall the coax, a little synthetic grease on the
connectors will help seal prevent corrosion, while CoaxSeal or similar
application will seal moisture out of the assembly.

Properly sealed, your installation will be trouble free for as long
as the coax jacket remains unbroken.

But as another poster commented, conditions haven't been good for
awhile. Be sure that's not what you're seeing. No need worrying about
things that don't require it.

I would guesstimate,replace the coax at least once every five years or
so.There is a BIG difference in the quality (read that,Big Bucks) of
coax too.
cuhulin

Yeah,,,,, outside,,,,, coax can SUCK!
cuhulin

coax,outside is like a weep.It sucks up all kinds of S..T.
cuhulin

FWIW - Many Crystal Radio Enthusiasts like to use Litz Wire
to build their Radio-Antenna Coils.

Litz Wire [Type 175/46] for Coils, Loop Antennas and
Crystal Radio Sets - Length 50 Feet
http://cgi.ebay.com/_W0QQitemZ300061128335
http://myworld.ebay.com/vanagon/
http://stores.ebay.com/RESCUE-ELECTRONIC-SURPLUS

Note - The right 'type' of Litz Wire can help a Crystal Radio to
perform up to it's full potential in the AM/MW Broadcast Band.


iane ~ RHF
.
|
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/ \
........!......

= = = On Dec 24, 1:38Â*am, "RHF" wrote:
= = = On Dec 23, 5:55Â*am, Carter-k8vt wrote:

RHFwrote:
QUESTION - What's Your Opinion "AntennaWire" : Solid -or- Stranded ?Electrically, I believe that there is no detectable difference.

Mechanically, strandedwireis used in situations where vibration and/or
flexing is present. Needles to say, an outdoor (as opposed to an attic)
antenna is subject to flexing and thus IMHO, strandedwirewould be the
better choice.

Now, you didn't ask about insulated vs. non-insulatedwireor regular
wirevs. 'Copperweld' (tm). Saving those for another debate, are we?

:-)

Carter
K8VTCarter [K8VT],

Yes most Solid or StrandedWiremay have very little
'difference' Electrically as aWireAntenna Element.
And Yes - StrandedWireof the same Size usually is
more durable then SolidWire.

EXCEPT - For Stranded "Litz"Wirewhich has each Strand
Insulated from the others and thus has a much greater RF
Surface Area for a given Size OD StrandedWireBundle.

ABOUT - LitzendrahtWire[LITZWIRE]http://home.earthlink.net/~jimlux/hv/litz.htmhttp://en.wikipedia.org/wiki/Litz_wire

TIP - WHEN TO USELITZWI
* Â*For short [ under 30-Feet ] Shortwave Listening (SWL)
Antennas - Consider usingLitzWireas the Multi-Wire
Antenna Element.
* Â*For In-the-Attic -and- In-the-Room Shortwave Listening
(SWL) Antennas - Consider usingLitzWireas the Multi-Wire
Antenna Element.
* Â*For Under-the-Eaves and Hidden [Stealth] No-See-Em
Shortwave Listening (SWL) Antennas - Consider usingLitzWireas the Multi-WireAntenna Element.

While it is notLitzWire"Flex-Weave" AntennaWire
is easy to work with and durable.
FLEX-WEAVE =http://www.davisrf.com/ham1/flexweve.htm
* Â*Flex-Weave AntennaWireis a sophisticated "Hybrid"
AerialWire.
* Â*Flex-Weave AntennaWireis sometimes referred to
as "WireRope" Ulta-Flexible AerialWire.
* Â*Flex-Weave comes in # 14 AWGWirecomposed
of 168 Individual Strands of Â*# 36 AWGWire.
- BareWire-or- InsulatedWire-
- - - HEY ! - You Can Always Say : " My Shortwave Listening
Antenna - I Use Flex-Weave ".

ABOUT - LitzendrahtWire[LITZWIRE] - TIP - When To UseLitzWirehttp://groups.yahoo.com/group/Shortwave-SWL-Antenna/message/11774
Â*.
Â*.
staying flexable and weaving my words - iane ~RHF
Â*.
Â*.
I-B Somewhere on "The Big Blue Marble"http://en.wikipedia.org/wiki/The_Blue_Marble
{ Earth - The Third Planet from the Sun }http://en.wikipedia.org/wiki/Third_planet_from_the_Sun
Â*.
Shortwave Listener Antennas =http://tinyurl.com/ogvcfhttp://group...e-SWL-Antenna/
SWL Antenna Group =http://tinyurl.com/ogvcf
Â*.
The Shortwave Listener's Blessing :
SWL BLESSING =http://tinyurl.com/s2bjm
May You Never Tire of Listening to the Radio and Always
have Strong Signals and Noise Free Reception ~RHF{ibid}http://groups.yahoo.com/group/Shortw...a/message/9233
Â*.
Tous Sont Bienvenus ! - - - Groupe par Radio
d'auditeur d'onde courte pour des Antennes de SWLhttp://groups.yahoo.com/group/Shortwave-SWL-Antenna/
Â*.
Alle Sind Willkommen ! - - - Shortwave Radiozuhörer
Gruppe für SWL Antennenhttp://groups.yahoo.com/group/Shortwave-SWL-Antenna/
Â*.
Tutti Sono Benvenuti ! - - - Gruppo Radiofonico
dell'ascoltatore di onda corta per le Antenne di SWLhttp://groups.yahoo.com/group/Shortwave-SWL-Antenna/
Â*.
Todos São Bem-vindos ! - - - Grupo de Rádio
do ouvinte do Shortwave para Antenas de SWLhttp://groups.yahoo.com/group/Shortwave-SWL-Antenna/
Â*.
Ð’Ñ�е Ð*адушны ! - - - Группа оператора
на приеме коротковолнового диапазона
Radio дл� Aнтенн SWLhttp://groups..yahoo.com/group/Shortwave-SWL-Antenna/
Â*.
¡Todos Son Agradables! - - - Grupo de Radio del oyente
de la onda corta para las Antenas de SWLhttp://groups.yahoo.com/group/Shortwave-SWL-Antenna/
Â*.
= = = = Plain Old American-English Translation = = = =
All are Welcome - - - To Join the Shortwave Listeners
(SWL) Antenna Group on YAHOO !http://groups.yahoo.com/group/Shortwave-SWL-Antenna/
Â*.
Â*|
Â*|
Â*|
/ \
.......!.......

www.devilfinder.com Super Long Distance Crystal Radios

Some good stuff there.Depending on how such a radio is built,it can
reach way out there.Crystal Shortwave Radios too.
cuhulin

Telamon wrote:
In article ,
Doug Smith W9WI wrote:

RHF wrote:
- You do want to use solid wire since the signals are collected
- on the surface of the wire for the best results.

QUESTION - What's Your Opinion "Antenna Wire" : Solid -or- Stranded ?

let the debate begin ~ RHF

If the signals are collected on the surface of the wire, wouldn't you
want to use *stranded* wire? For the same gauge, it would have a
greater surface area.

Due to the skin effect I would suggest stranded would also have lower
resistance: lower losses delivering the signal from the outer parts of
the antenna to the feedline.

But I believe the difference is negligible. Really, the only
consideration for a receiving antenna should be mechanical: how hard is
it to get the antenna strung and will it *stay* strung once you string it?

I use #14 stranded, sold at Home Depot for home wiring.

I do have a 700' Beverage using solid aluminum electric fence wire.
ONLY because it was dirt cheap. The stuff is really hard to work with.
(and I managed to snap it twice trying to pull it through the woods)

What makes the skin effect occur is electrons repulsing each other. The
higher the frequency the higher the electric field flux so the
electrons tend to occupy the conductor outer skin. Even with multiple
insulated conductors bundled together the electrons would only occupy
the outside of the most outside conductors at higher frequencies.
Multi-stranded wire will not help once you go above a certain
frequency. You would have to calculate using the frequency of operation
and the size of each strand with the number of strands to know if a
litz type wire will help you increase the conductance of a wire path.

Usually this number is less then a few megahertz for most available
litz wire so that type of wire is useful for AMBCB and lower frequencies.

If the conductors are not insulated from each other then they act as one
conductor.

--
Telamon
Ventura, California

I agree with Doug on the Home Depot #14 stranded. I think I paid about
11 bucks for a 500' spool.

Got a question for you Telamon. I think you are power supply guy like
me. Why is it that for Ham radio tank coil people don't use litz wire?
Most tank coils are made from Copper tubing I see. I suppose the
surface area of a 3/8" copper tube would be fairly large and does ok,
and litz would require a coilform. The reason I asked is because I
remember a large battery charger at UW *Go Badgers!* It was a large
resonant 500kw battery charger that used some litz wire.

73
NEO

On Dec 27, 5:56 am, "N9NEO" wrote:
Telamon wrote:
In article ,
Doug Smith W9WI wrote:

RHF wrote:
- You do want to use solid wire since the signals are collected
- on the surface of the wire for the best results.

QUESTION - What's Your Opinion "Antenna Wire" : Solid -or- Stranded ?

let the debate begin ~ RHF

If the signals are collected on the surface of the wire, wouldn't you
want to use *stranded* wire? For the same gauge, it would have a
greater surface area.

Due to the skin effect I would suggest stranded would also have lower
resistance: lower losses delivering the signal from the outer parts of
the antenna to the feedline.

But I believe the difference is negligible. Really, the only
consideration for a receiving antenna should be mechanical: how hard is
it to get the antenna strung and will it *stay* strung once you string it?

I use #14 stranded, sold at Home Depot for home wiring.

I do have a 700' Beverage using solid aluminum electric fence wire.
ONLY because it was dirt cheap. The stuff is really hard to work with.
(and I managed to snap it twice trying to pull it through the woods)

What makes the skin effect occur is electrons repulsing each other. The
higher the frequency the higher the electric field flux so the
electrons tend to occupy the conductor outer skin. Even with multiple
insulated conductors bundled together the electrons would only occupy
the outside of the most outside conductors at higher frequencies.
Multi-stranded wire will not help once you go above a certain
frequency. You would have to calculate using the frequency of operation
and the size of each strand with the number of strands to know if a
litz type wire will help you increase the conductance of a wire path.

Usually this number is less then a few megahertz for most available
litz wire so that type of wire is useful for AMBCB and lower frequencies.

If the conductors are not insulated from each other then they act as one
conductor.

--
Telamon
Ventura, CaliforniaI agree with Doug on the Home Depot #14 stranded. I think I paid about
11 bucks for a 500' spool.

Got a question for you Telamon. I think you are power supply guy like
me.

- Why is it that for Ham radio tank coil people don't use litz wire?
- Most tank coils are made from Copper tubing I see.
- I suppose the surface area of a 3/8" copper tube would be fairly
large
- and does ok, and litz would require a coilform.

Why Cooper Tubing -over- Litz Wire :
Raw Power Handling Ability and Relative Lower Cost.

yes it is that simple - iane ~ RHF


The reason I asked is because I
remember a large battery charger at UW *Go Badgers!* It was a large
resonant 500kw battery charger that used some litz wire.

73
NEO- Hide quoted text -- Show quoted text -