Multi Use Mobile Antenna
Moderator: Queue Moderator
-
Stage 2
- Posts: 90
- Joined: Sat Mar 19, 2005 7:08 am
- What radios do you own?: HT1000,MT1000, HT50,MAXTRAC
Multi Use Mobile Antenna
I thought I would throw this out to see if I missed a better choice than what I am about to go with. I searched around many different companies for a mobile antenna that will cover both 2 meter and 70cm hams bands as well as M.U.R.S along with GMRS UHF. The best I can find which appears to have the ranges to do this is the Comet model CA-2X4SR. Has anyone else looked into this for these ranges and come up with something comparable or, better? The Comet above is rated for 1.5 or better from 140 to 160 Mhz and, the same 1.5 or better for 435 to 465 Mhz. Thanks in advance.
RAILROADS: AMERICA'S MOST VITAL TOOL FOR ENERGY CONSERVATION.
Don't count on it, Vommett antennas suck, get a real antenna!!!
The only broadband 'antenna' is a 50 ohm resistor! And sometimes the resistor works better than the Vommett.
The dual band antennas will not cover both 144 to148 AND 154, and 440 to 459 AND 462 at the same time in the same antenna, or someone lied.
The good commercial antennas cover either 144 to 150 OR 150 to 162 depending how they are ordered, and 'cut' to. So having GMRS AND UHF ham won't work.
The Comtelco A1131A is about as broadbanded as they get, comes in 144-148 and 440 -450, or a simmular range. Lisa can custom tune them for your ranges. The A1833-40 even has a narrower freq range, but more gain. And you are talking less money, the A1131 goes for $26,and IS very professional quality.
The only broadband 'antenna' is a 50 ohm resistor! And sometimes the resistor works better than the Vommett.
The dual band antennas will not cover both 144 to148 AND 154, and 440 to 459 AND 462 at the same time in the same antenna, or someone lied.
The good commercial antennas cover either 144 to 150 OR 150 to 162 depending how they are ordered, and 'cut' to. So having GMRS AND UHF ham won't work.
The Comtelco A1131A is about as broadbanded as they get, comes in 144-148 and 440 -450, or a simmular range. Lisa can custom tune them for your ranges. The A1833-40 even has a narrower freq range, but more gain. And you are talking less money, the A1131 goes for $26,and IS very professional quality.
The standard quarter wave antennas (6" spike) are fairly flat across a wide range of frequencies. I've had a lot of luck with them on VHF, going from 2 meters to 160 MHz with very little problem.
As others have mentioned, buy the good stuff. I'm a diehard Antenna Specialists and Decibal Products man. NOTHING outperforms their products and they last for decades. Cushcraft makes some good stuff. Maxrad is OK but certainly not excellent.
Walk ... no, RUN from those antenna manufacturers that specifically target amateur radio end users. They are all designed to give penny-pinching hams a cheap (throwaway) antenna with some poorly constructed whistles and bells, making them think they got a steal when compared to real antennas. Comet antennas are crap. Not a lot of luck with Diamond stuff either.
Spend a quarter once rather than 15 cents three times over.
As others have mentioned, buy the good stuff. I'm a diehard Antenna Specialists and Decibal Products man. NOTHING outperforms their products and they last for decades. Cushcraft makes some good stuff. Maxrad is OK but certainly not excellent.
Walk ... no, RUN from those antenna manufacturers that specifically target amateur radio end users. They are all designed to give penny-pinching hams a cheap (throwaway) antenna with some poorly constructed whistles and bells, making them think they got a steal when compared to real antennas. Comet antennas are crap. Not a lot of luck with Diamond stuff either.
Spend a quarter once rather than 15 cents three times over.
Antennex, Larsen, but no, not vomit comet or Diamond, though Diamond is said to be a little better than Comet. Comet is for cleaning sinks, not radiating RF through a winter!
Chris,
Hamming 31 years
http://www.wa2zdy.com
Wesley Chapel, Pasco County, Florida
Snow? What's that?!
The human race is proof that Darwin was wrong.
Hamming 31 years
http://www.wa2zdy.com
Wesley Chapel, Pasco County, Florida
Snow? What's that?!
The human race is proof that Darwin was wrong.
If you want to cover both 440 and GMRS you will probably need to stick with a quarter wave as mentioned in a previous reply. The gain antennas by Larsen, Maxrad, Antennex etc are rather narrow band on 460. It requires some compromise tuning to even get them to work on a radio that has both 450 and 460 business frequencies. The bandwidth is only about 10 MHz for less than 1.5 SWR and it degrades rapidly beyond that.
If you only need GMRS simplex and your ham repeaters are all high side input, you may be able to cut a gain antenna for about 455 and have an SWR around 1.5 to 1.7 on 462 and 448 but SWR probably will be over 2.0 on 467 and 443.
If you only need GMRS simplex and your ham repeaters are all high side input, you may be able to cut a gain antenna for about 455 and have an SWR around 1.5 to 1.7 on 462 and 448 but SWR probably will be over 2.0 on 467 and 443.
Broadbanded antenna.
Hello.
As a rule, the wider the antenna, the greater the bandwith.
A stovepipe or discone is as broadbanded as you are going to get, but not always practical.
The other way is to use a little math.
A quarter wave 6 meter antenna will work well on 2 meters, why?
The answer is that 2 meters is a multiple of 6.
50 MHz X 3 = 150 MHz.
AND 150 MHz X 3 = 450 MHz.
A copper plated tape measure makes an excellent antenna element for some portable applications.
As a rule, the wider the antenna, the greater the bandwith.
A stovepipe or discone is as broadbanded as you are going to get, but not always practical.
The other way is to use a little math.
A quarter wave 6 meter antenna will work well on 2 meters, why?
The answer is that 2 meters is a multiple of 6.
50 MHz X 3 = 150 MHz.
AND 150 MHz X 3 = 450 MHz.
A copper plated tape measure makes an excellent antenna element for some portable applications.
-
Stage 2
- Posts: 90
- Joined: Sat Mar 19, 2005 7:08 am
- What radios do you own?: HT1000,MT1000, HT50,MAXTRAC
Thanks for all the responses. I had no idea that Comet had had it's own fan club! 
I will look into the suggestions made to see what I can find that best meets my requirements. I just don't want to drive something that looks like Sputnik 5 on wheels like some of the vehicles I see on the road. I don't expect peak performance on all bands,but, just something that will work well enough so I can make do with a single antenna if possible. If worse comes to worse I will omit one of the bands or, maybe pop the little 6 inch 1/4 wave I have up there too to bridge the gap as it isn't really noticeable.
I will look into the suggestions made to see what I can find that best meets my requirements. I just don't want to drive something that looks like Sputnik 5 on wheels like some of the vehicles I see on the road. I don't expect peak performance on all bands,but, just something that will work well enough so I can make do with a single antenna if possible. If worse comes to worse I will omit one of the bands or, maybe pop the little 6 inch 1/4 wave I have up there too to bridge the gap as it isn't really noticeable.RAILROADS: AMERICA'S MOST VITAL TOOL FOR ENERGY CONSERVATION.