On 1-23-2012 04:43, Phil wrote:
> Hello , am looking for advise on a VHF Omni directional antenna for a small
> fixed base operation , looked at a commercial ant. and the price is a little
> high for a 1/4 wave vertical , am sure the quality is there but am wondering
> if I could modify a Ringo or something else to work just as good , would
> have it resonate on 123.000 as this is our Unicom freq., a little gain would
> be OK .
> Phil L.
Of course, there is always the standard 1/4 wave antenna made with an
SO-239 chassis mount antenna connector. 1/16" brass rod from
Menards/Home Depot, etc. works great for the elements.
At 123 MHz, the vertical element for the center pin should be just shy
of 23" total from tip to bottom of the solder cup on the connector
(22.83" to be exact, but not extremely critical) and the radial elements
should be about 24" and bent so they droop at a 45 degree angle.
A standard PL259 connector fits nicely inside a piece of 3/4" copper
water pipe. You can cut some slots about 3/4" long in the end of the
pipe with a hacksaw , slide the PL259 in until the SO239 bottoms out
against the pipe and secure with a hose clamp. I would use a short
piece of copper pipe as a long 10' piece might be apt to bend over in