VHF "Low Profile" antennas. Any success?

Marc · Post by **Marc** » Thu Sep 09, 2004 1:22 am

Hello,

Well one of our tow contractors ordered a new truck. Nice new Ford F-550 wheel lift style truck. Anyway, he is the one that gets to do all the low clearance and parking garage calls, and he is trying to keep the height of the truck as low as possible. One concern is the 2-way antenna.

He is now on one of our VHF high-band, simplex channels. Has anyone here had any success with those "low profile" antennas, like whipless coils and discs? The word I'm getting is that they pretty much suck. I see Sti-Co has some kind of super-flexible 1/4 wave, but I don't have any experience with that company.

Anyone have any suggestions? I'm all ears. I guess, as a last resort, we could probably move him to our 800 MHz conventional repeater, but that would just add to the load on that dispatcher. They're busy enough as it is. :-)

Thanks,

Marc C.
----------
Phoenix, AZ
AAA/Arizona - KOL575 (VHF) - WNSK486 (800)

nmfire10 · Post by **nmfire10** » Thu Sep 09, 2004 4:36 am

I've never actually used a VHF lo-pro antenna... mainly because I've heard the same thing as you. They all suck.

The shortest antenna will probably be a 1/4 wave at 19". Get the kind with a .062 thickness whip or something like that. Those are very flexible and shouldn't have a problem.

JohnWayne · Post by **JohnWayne** » Thu Sep 09, 2004 5:26 am

The low profile VHF antennas, like an Antenex Phantom, work alright for around town type usage, but don't expect super great performance. Their real claim to fame is the way they have their radiation pattern. It's such that signals being bounced around buildings and such are not as attenuated. I don't know how well that concept really works, but the antennas seem to work well in urban areas. One caveat on the VHF Phantom is that the bandwidth is very small, but that wouldn't be a problem if you are just using one channel.

The STi-Co flexible antennas are ok, but the coating will rub off over time if you are constantly hitting objects such as roof beams in a parking garage.

My suggestion is to fender mount a 1/4 wave whip antenna. You'll get the benefits of the full-size antenna, and it will still clear the roof line. You could even do a 5/8 wave if it will fit.

I carry the Phantoms and the Sti-Co flexibles, as well as 1/4 waves and fender mounts. Let me know if you need anything.

Thanks,
Jeff

Marc · Post by **Marc** » Thu Sep 09, 2004 12:01 pm

Interesting. Maybe the fender mount is the way to go. How do the Sti-Co flexibles compare to regular ones, pricewise? I don't know anyone here that is a dealer for them.

Marc

Post by Pj » Thu Sep 09, 2004 12:11 pm

I believe that the antennx and others have about 1mhz to play with. If your just using simplex, you should be ok, but again, your not going to get the performance of a 1/4-1/2 wave antenna, but will work.

BNBEquipement · Post by **BNBEquipement** » Thu Sep 09, 2004 5:08 pm

I have a comtelco antenna on my truck for clearance issues. I went with comtelco due to the fact that Maxrad and Antennex lo pro antennas are not rated for 100w! The comtelco is about the size of an upside down coffee cup on the top of the truck.

I have found that it will tx as well as a 1/4 wave antenna, but it does not rx as well. I have a 5/8 wave Maxrad behind the seat for a a quick switch if I need to Rx better.

I also use Maxrad 800 and UHF lo pros they work as well as the 3db's that were there, and to some extent better. Admittedly they are both transmitting to and recieving from repeaters with in 30 miles.

ExKa|iBuR · Post by **ExKa|iBuR** » Thu Sep 09, 2004 6:14 pm

Just a suggestion here;

It's really ugly, but why not look at a Railroad Antenna with the radome?

Sinclair makes a nice one, it's the Excaliber 221. It's specs are:

148-174MHz
Omnidirectional, Unity Gain, 300 Watts, physically it's 4 inches high, 2.2 inches wide and 23 inches deep.

They don't look the best, but they do work really well and don't take up much real estate. You can paint them to whatever colour you want to with no problems.

I had one of these on my old car, it worked way better than even a vertical 1/4 wave could ever hope to.

-Mike

Marc · Post by **Marc** » Fri Sep 10, 2004 12:25 am

Hmm. I hadn't thought of that one. I'll have to keep that one in mind. I don't I've ever seen a tow truck with one of those. :-)

Just thinking here... what about a glass mount placed on the lower front corner of the windshield? I don't think I would do that personally, but has anyone tried it? Probably wouldn't work as well as a fender mount 1/4 wave, I'm thinking.

Marc

va3wxm · Post by **va3wxm** » Fri Sep 10, 2004 5:28 am

Glass mounts blow. Use it only as a last resort!

ricciticcitembo · Post by **ricciticcitembo** » Fri Sep 10, 2004 11:37 pm

I'm using the stock Honda Antenna on the left rear quarter panel
of my Accord with the Sti-Co adapter thingy running a HHCH Dual Band 110W.

And I must say that performance is way better than I expected it to be.
I can still talk simplex 30 miles reliably, which is amazing considering the terrain.

Stan USPSS says the comprod disguise antennas are even better.

So I'd look there, or just maybe use a 19 incher on the fender.

It ain't gonna outperform an NMO in the center of the Roof, but it
should be acceptable.

The antenna becomes directional when mounted in a place other
than the center of the roof, especially when it is in the far corners
like the front fender or rear quarter panel.

This directionality is the only thing I really notice as compared to
having the Center roof mount NMO.

The Antenna whether it be a 1/4 Wave 19 incher or the Stock
Honda antenna with the FBI Sti-Co Box performs very nearly
identically with only a .3 db loss to which I attribute the TNC
connectors and the relative deep pockets of Uncle Sam to buy only the best.

It is only the mounting location that seems to make any difference.

I tried both antennas in both locations on two different vehicles
(a car and a van) and came to the same conclusions as noted above.

Hope this helps.

And now I have to redesign the suspension system on the Honda
because the damm Dual Band is so heavy that It looks like I'm
carrying around a dead body in the trunk. Can't have that.
Thank God for Neuspeed.

olderookie · Post by **olderookie** » Tue Sep 28, 2004 6:40 am

ok its simple go to the hedache rack where the light bar is mounted and add some metal or do a right angle install I have see it done by bending a 1/4 wave with a perment mount on the fender.

I was constantly putting my mag mount back on the roof I wanted to change it but no longer drive a wrecker.

what I am sayin in a nutshell go just behind the cab and look there for mounting options

Joe

Lord Windeshmere · Post by **Lord Windeshmere** » Tue Oct 05, 2004 3:06 pm

I've had good performance from low-profile Maxrad antennas. I'm not affiliated with them in any way, but we've bought quite a few of their antennas. I've used their l/p antenna for UHF and I've been pleased with that.

KitN1MCC · Post by **KitN1MCC** » Wed Oct 06, 2004 4:54 am

the locomotive ant will work really well. but go with the skate not the figlass one it will look better

or the 5/8 comtelco on the fend i have sever fords set upliek with on VHF simplex they work great