I wouldn't hesitate to say this was the best ground plane antenna ever built,
those that ever had one know what i'm talking about. These are rare and hard to
find. $80 plus shipping for the antenna and instruction sheet.

(Reg1647) wrote:
I wouldn't hesitate to say this was the best ground plane antenna ever
built, those that ever had one know what i'm talking about. These are
rare and hard to find. $80 plus shipping for the antenna and instruction
sheet.

They were great antennas, no doubt. Your price seems fair if it's in
nice shape. (hubs good?)

Steveo wrote in message ...
(Reg1647) wrote:
I wouldn't hesitate to say this was the best ground plane antenna ever
built, those that ever had one know what i'm talking about. These are
rare and hard to find. $80 plus shipping for the antenna and instruction
sheet.

They were great antennas, no doubt. Your price seems fair if it's in
nice shape. (hubs good?)

mopeadope, that's 320 trips to the restroom at Petro...We know that is
just another 1/2 days' work for you.

Actually, the Avanti (and later Antenna Specialist) Sigma 5/8 was a better
antenna than the Super Penetrator.

It had an elevated feed and low loss feedpoint. The Penetrator was a good
antenna, but not better.

Master Chief

http://www.a1antennas.com/


I wouldn't hesitate to say this was the best ground plane antenna ever built,
those that ever had one know what i'm talking about. These are rare and hard
to
find. $80 plus shipping for the antenna and instruction sheet.

Wrong! - But thank you for playing.

I've had both the Avanti Sigma5/8 & the Hy-gain Penetrator 500 on the same mast, radio, coax, etc., and the Sigma only outperformed the Penetrator in terms of receive, and then only by a tiny amount, as in 1/2 needle width, and only until I removed the 10", 45* downward-bent top-hat radials on the Penetrator, leaving the top simply a small point of aluminum, just like that of the Sigma5/8 design, and extended the overall length of the P500 radiator to reclaim the lost 10", at which point it received the same as, or slightly better than, the Sigma5/8.

At all points the Penetrator outperformed the Sigma5/8 on TX, albeit only by a full needle width. This is due to the slightly better efficiency of the Penetrator's Beta match and the fact the radials nullify a small percentage of the out-of-phase bottom 1/8wave of the antenna, which on a 5/8 is reverse current phase from the next 1/8wave up on the antenna, thus providing a slightly lower radiation angle than that of the Sigma5/8.

The high current node on a 5/8 is ~13.5' above the bottom of the radiator, therefore, what happens at the bottom 1' is almost insignificant and not a reason for anything other than superstition in believing this is a negative in the design of the P500.

In addition, the construction of the Sigma5/8 is SH!T in comparison, ie: weak, smaller and much more easily bent tubing material for the radials, wimpy radial ends made from 1/8 solid aluminum rod mounted to smashed & drilled tubing ends which bend easily in wind or under the stress of even a large bird landing / take-off, weak and brittle radial hub which tends to crack under tightening and spins easily, wimpy too-thin wall fiberglass radiator insulator which cracks and snaps off in decent wind, too-heavy non-suaged radiator tubing making the radiator heavy and more whippy in the wind than the P500.

All-n-all, I had purchased both because I decided the best of the best was one of those two awesome looking antennas, tested them, one against the other, and sold the Sigma5/8 but kept the Penetrator 500 - for many obvious reasons.

I got the Sigma5/8 back from the guy I sold it to and have it today... 4sale, that is.

Sigma5/8

do you have a pentrator 500 ant if so would you conntacn me

Still lookin for a Penetrator for sale----

And I am still looking for one--

The 117 Super Magnum was a better antenna then the Penetrator, but the design flaw is that the ground plane elements has to be at a 45* angle in order for them to work properly.

When the element is straight out at a 90* angle and droops - it is not as effective and does not do anything.

10 meters and 11 meters is only about 1 mhz difference, or about 4 inches max of length to tune it up.
If the band is open, which ever direction it propogates in, you can talk, reguardless of how much transmit power you use.
I talked half of Europe yesterday with 100 watts on 10 meters SSB.
All I was using was a old wore out Solorcon 99A and some equally wore out Radio Shack RG 8 coax.

So the question is - how much gain should you expect from a verticle antenna with ground planes.
The Manufacturers claims that you should have 3 DB of gain, but in fact it is usually less then 2 DB.