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At 12 miles out (level ground; the West TX Plains) to-and-from another SBB-7NMO antenna mounted 25ft in the air at my house, ... I made a Real-World Performance Test between the two antennas ... AND ... My OPINION is that the SBB-7NMO (without any modifications) performs better than the CA-2x4SR. I was using 5 Watts Transmission from a BTECH-GMRS-V1 and got clear transmits and receives ... The CA-2X4SR transmitted with some-static that the SBB-7NMO didn't have ... (Note: This test was made 3 times by switching-out both antennas to verify this difference). So, I decided to check the SWR on the SBB-7NMO antenna sitting in the middle of the roof of a 1999 2-Door Tahoe ... the results are as follows using the Low Power Setting with a BTech UV-50X2 ... (NOTE: BTech Specifications say 10watts; I'm showing 20watts on my SureCom SW102 Digital SWR Meter): ----------------------------- SBB-7NMO - No Modifications ----------------------------- 462.5500 GMRS 15 1.40 462.7250 GMRS 22 1.42 467.5500 REPT 15 2.00 467.7250 REPT 22 2.01 151.8200 MURS 01 2.09 151.8800 MURS 02 2.11 151.9400 MURS 03 2.13 154.5700 MURS BL 04 3.71 154.6000 MURS GR 05 3.73 146.5200 2M 1.10 446.0000 70CM 1.00 ----------------------------- I contacted a Comet Representative about what needed to be done to tune the SBB-7 Antenna for Dedicated GMRS use ... His reply was the following: I have 4 of these antennas and decided to take a chance of destroying one to find out IF some modificaton(s) would improve the SWRs. I found the following adjustments (or cuts) accomplished My Goal ... as follows: -------------------------------------------------------- SBB-7NMO - Rods Cut Lower-3/4" Middle-3/8" Upper-3/8" -------------------------------------------------------- 462.5500 GMRS 15 1.00 462.7250 GMRS 22 1.00 467.5500 REPT 15 1.15 467.7250 REPT 22 1.15 151.8200 MURS 01 1.45 151.8800 MURS 02 1.51 151.9400 MURS 03 1.54 154.5700 MURS BL 04 2.96 154.6000 MURS GR 05 2.99 146.5200 2M 1.54 446.0000 70CM 1.09 -------------------------------------------------------- - In conclusion, I have shopped around for quite some time looking for a High-Gain GMRS Mobile Antenna ... but ... without finding anything to my satisfaction ... BUT ... with THIS Modification, My Quest has Finally Ended !!! The GMRS Transceiver that I will be dedicating to this modified Comet SBB-7NMO Antenna is a BTech GMRS-50X1 which has 3 power settings 50 Watts, 20 Watts, and 5 Watts. Just for completeness, the Mag Mount that I am using with all of my antennas is the "TRAM 1267R 5 1/2" Magnet NMO Mounting with Rubber Boot" that I have purchased from Amazon. Happy GMRS'ing !!!, FWI .