Hy-Gain 500 Penetrator...

[bear]

I just bought a really nice 500, but the top hat radials are missing, the rest is all there. Does anyone have the specs on them? It's really appreciated.

 

[BOOTY MONSTER]

007 will be here shortly to tell you everything you want to know about the 500 ...... and more

 

[CDX-007]

I just bought a really nice 500, but the top hat radials are missing, the rest is all there. Does anyone have the specs on them? It's really appreciated.

007 will be here shortly to tell you everything you want to know about the 500 ...... and more

Sorry for the delay, I've been all caught up in the other threads about the SGM and didn't even see this one until a minute ago. Next time someone send a PM to alert me!

The top hat radials are 9.5" from the center of the screw, but I removed mine and added 9" to the height of the main radiator element for a total of 274" and have a needle's width better receive now. I don't believe the top hat radials do anything other than look cool and designate the fact it is a Penetrator500 and not one of the other 20 antennas which were it's contemporaries.

If it was an antenna which was significantly shorter than a 1/4 wave, the top hat radials would act as a capacitance hat and help the overall radiation efficiency but this is a .64, (just slightly longer, ~6.5", than a .625 5/8 wave) and I do not see a need for a top hat unless you live in an area with extreme humidity and plan to run high power, then it might help prevent corona discharge from the tip, though that's even debatable because the radials terminate abruptly instead of in a smooth fashion.

If you can add about 8"-10" of 1/2" tubing or find a piece of 3/8" which is about 8"-10" longer than the top piece, you'll find it will tune nicely for CH38 around 273.5"- 274" from the bottom insulator, add an inch or two if you prefer to operate lower in the band.

Here's a link to the manual: http://www.cbtricks.com/ant_manuals/hygain/model_500/index.htm Keep in mind the P500 was designed to tune as low as 26.000MHz so those lengths mentioned in the manual pdf tend to be too long for centering higher, such as Ch.38.

You're going to love that antenna, and don't forget to ground it well to help bleed off static!