Discussion in 'Mobile Radio Systems' started by KC9SGU, Jan 26, 2011.
Any ideas what i could use for this? i will be using a medium sized spring
I use a stainless steel CB whip cut down to 54" overall length. Works great on 6m (for FM).
WB2WIK has the best suggestion. The stainless 102" whip cut down would work the best. That is unless you have a height situation, you could use a wound fiberglass one and cut it down as well.
no height situation that i can think of, it likely won't stick up any higher than my larson 2/70 that's mounted on the roof. also, wouldn't it be best to cut it to either 59" or 88.5" for either a 1/4 wave or 3/8 wave?
Around 54 inches IS a quarter-wave for 52.525 MHz. If he wants to use it for the low end then about 56 inches would be a quarter-wave.
Depending on the actual mount, the whip may have to be a little bit shorter for lowest SWR.
Using a 3/8th wavelength might get "tricky" matching it to 50 ohm coaxial cable.
An antenna 59 inches long for a quarter-wave would be resonant at about 47.6 MHz.
Funny, no one mentioned a loop! If you're going to operate SSB, it is the way to go!
I'm set up, where in I can switch between a 6 M vertical, and the M2 loop. About 90% of the time, the difference is greater than 20 dB, and when the band is marginal, the loop wins hands down! You can indeed mount it on a ballmount, but it better be a big one, like an old GE Master ballmount made of cast iron!
nice to see you on here Alan, i'm a regular on your site since getting my license, mostly to make sure i don't have too many issues with my mobile setup
A "loop", or as they have been called for decades when used mobile, a "halo" or "squalo" work fine for SSB. But, if for FM, then the antenna needs to be vertically polarized. Also, for line of sight and most tropo activity, for SSB horizontally polarization works best. But, for any kind of "skip", polarization of the antenna doesn't usually have much effect since the polarization of the signal is usually "skewed"
And keep in mind that the height of your ball mount & spring is part of the overall antenna length; trim the whip shorter, accordingly.