Mobile Antenna Comparison

[doctordave]

Out of curiosity, I purchased the Comtelco tri-band scanner antenna (11331B-Z) as well as the Maxrad Bmax1000 scanner antenna (both have similar commercially advertised coverage ranges for VHF-High, UHF & 800 MHZ public safety bands). Against these, I compared a .062 whip cut at 18.5 inches. All were used w/ an NMO mount on my stationary vehicle & monitoring on my Uniden 996.

After testing for reception of a number of proximal & near edge of range fixed stations on 39, 151, 152, 155, 159, 460, 856 & 868 MHZ.....I was able to note no obvious differences in terms of signal strength bars or audio quality - across all 3 antennas. Not at all a scientific study.....but some food for thought for those who might be seeking a basic antenna to use on such bands.

I must admit that I was impressed with the performance of the $8 whip against the $25-30 antennas. For a more detailed comparison of a large number of antennas, the northwestintercepts page is always a great resource:
http://www.northwestradio.com/interceptnw/antennas.htm

 

[zz0468]

I'm not at all surprised at your results. I've always just used an 18" whip for scanner reception. It works just fine for air band and above.

 

[mjthomas59]

I just switched from a NMO150 Larsen to a NMO40Larsen and i must say i didn't get what i was expecting. the NMO40 recieves infinetely better on 800 mhz than the NMO150. There really is no comparison at all in that range. However what i wasn't expecting is the absolutely horrid reception on the VHF-HI band with the NMO40. I figured it should perform pretty well, and i was definetely mistaken. I think i'm just going to have to run the NMO40 on a lowband scanner and possibly a 1/4 wave VHF-HI because i refuse to put 2 50" antennas on my car.

Another thing that i found odd is that on the Larsen webpage is says the whip on the NMO40 should come to 49". The one i got measures about 55". I may try cutting it down, the cutting chart recommends somewhere around 44 inches for a trunk mount. That seemed awfully short to recieve vhflo, but what the heck do i know.

Anyone know if cutting the NMO40 down to about 44inches would also improve my vhf-hi reception? Thanks

 

[zz0468]

I don't think cutting it to 44" is going to help high band reception at all. It's probably the loading coil, not the length of the whip, that is ruining reception on highband.

Like I said in my previous post, an 18" whip usually works fine for vhf high band and higher; in my experience low band generally requires a seperate antenna. The fact that your NMO40 works at all on 800 is a fluke.