Tube and Twin lead Slim Jim
 

On Jun 2, 4:51*am, Ian Jackson
wrote:
In message , Cecil Moore
writes

JIMMIE wrote:
Whats the advantage of the Slim Jim over a plan old J antenna.

Apparently, the take-off-angle:

http://www.para.org.ph/membersarticl...Slim%20Jim.htm

I'm sure that W4RNL did a comparison. It might be in here.
http://www.scribd.com/doc/8511817/Some-JPoles-That-I-Have-Known-4
http://www.cebik.com/
If it's not in there somewhere, a Google will be necessary.

Essentially, the answer was 'not a lot', except that the Slim Jim
version (the one with the folded-over top) had a slightly wider
bandwidth / flatter SWR plot.
--
Ian

Tube and Twin lead Slim Jim
 

"Sal M. Onella" wrote in message
...

"JIMMIE" wrote in message
...

snip

Dave,That was my thoughts on it also. Two wires
very close togethether with in phase and more or
less equal currents just adds up to a fatter
wire.

Not a fatter wire with twice the current?

Recall the colinear J-pole, The two currents are stacked and fed in phase
by means of the phasing section. Yes, I realize the currents in the Slim
Jim would appear to cancel.

I'm going to have to build one of these and see what it does. I have a
lot
of twinlead and I have a precision RF generator. I always wanted my own
antenna range; tomorrow's the day. Maybe Tuesday.

Hi "Sal"

I share your thoughts about a pattern range. I recently talked my buddy
into writing a program that plots Elevation Plane patterns of an antenna
when scaled to a frequency sent from any Polar Orbiting Satellite. I use
it alot using the 137 MHz beacons sent from NOAA satellites. Some HAM
satellites could be used. There are also L-band beacons sent from the NOAA
satellites.

Jerry KD6JDJ

Tube and Twin lead Slim Jim
 

"Jerry" wrote in message
...



snip


I share your thoughts about a pattern range. I recently talked my
buddy
into writing a program that plots Elevation Plane patterns of an antenna
when scaled to a frequency sent from any Polar Orbiting Satellite. I use
it alot using the 137 MHz beacons sent from NOAA satellites. Some HAM
satellites could be used. There are also L-band beacons sent from the
NOAA
satellites.

That's an interesting approach. Thanks.

Tube and Twin lead Slim Jim
 

"Sal M. Onella" wrote in message
...

"Jerry" wrote in message
...



snip


I share your thoughts about a pattern range. I recently talked my
buddy
into writing a program that plots Elevation Plane patterns of an antenna
when scaled to a frequency sent from any Polar Orbiting Satellite. I
use
it alot using the 137 MHz beacons sent from NOAA satellites. Some HAM
satellites could be used. There are also L-band beacons sent from the
NOAA
satellites.

That's an interesting approach. Thanks.

Hi "Sal"
If you ever get involved with that Pattern Range, Patrik Tast publishes
information on his program on the web. Everything Patrik does is *hobby
related* and available free. Nothing I do is sophisticated or difficult to
reproduce or to improve upon.
I was using Excel to plot the RSSI level before I asked Patrik to make a
program to display the signal strength in polar form. I can get actual
patterns that Very closely resemble EZNEC plots.

Jerry KD6JDJ

Tube and Twin lead Slim Jim
 

"Jerry" wrote in message
...

"Sal M. Onella" wrote in message
...

"Jerry" wrote in message
...



snip


I share your thoughts about a pattern range. I recently talked my
buddy
into writing a program that plots Elevation Plane patterns of an
antenna
when scaled to a frequency sent from any Polar Orbiting Satellite. I
use
it alot using the 137 MHz beacons sent from NOAA satellites. Some HAM
satellites could be used. There are also L-band beacons sent from the
NOAA
satellites.

That's an interesting approach. Thanks.

Hi "Sal"
If you ever get involved with that Pattern Range, Patrik Tast publishes
information on his program on the web. Everything Patrik does is *hobby
related* and available free. Nothing I do is sophisticated or difficult
to
reproduce or to improve upon.
I was using Excel to plot the RSSI level before I asked Patrik to make a
program to display the signal strength in polar form. I can get actual
patterns that Very closely resemble EZNEC plots.

Thanks. Whatever I set up will probably be for signal strength A/B testing
between antennas at a fixed distance.