I heard about every frequency has a harmonic of itself multiplied by a number. I do not know the equation but being adventurous I figured a cheap cb antenna might serve my purpose on certain frequencies. Listen to me please if you have a critical thoughts against this thread I am only trying to bring forth an alternative for those who might not have means but do have a cb antenna laying around doing nothing..
I am experimenting with a $15 Walmart antenna.
Since CB antennas are tuned for the 27mhz range.I am trying my luck on these harmonics of 27mhz with my experimental antenna.
27mhz frequency input (CB band) BEST RESULTS
2nd harmonic 54mhz (Top of 6 meters) NO RESULTS NO CONDITIONS
3rd harmonic 88mhz (bottom edge of FM Broadcast) GOOD RESULTS
4th harmonic 108mhz (Top end of FM broadcast. Start of Aviation band) GOOD RESULTS
5th harmonic 135mhz (Top of Aviation band) FAIR RESULTS
6th harmonic 162mhz (NOAA Weather Radio area of the dial) GOOD RESULTS up to 50 miles
7th harmonic 189mhz NOT TESTED
8th harmonic 216mhz NOT TESTED
10th harmonic 270mhz (Mil Satcom but not a good idea to use cb antenna for this) NOT TESTED
I do not think this would work using a high quality CB antenna. It may work on a low end cheapo like mine
Its worth a shot if you do have a cb antenna laying around to get ya started scanning CB to VHF.
Post your results.
Edit: May I add that I am using RTL-SDR NESDRSmart and HDSDR for the receiver in this test. Your mileage WILL vary!
I am experimenting with a $15 Walmart antenna.
Since CB antennas are tuned for the 27mhz range.I am trying my luck on these harmonics of 27mhz with my experimental antenna.
27mhz frequency input (CB band) BEST RESULTS
2nd harmonic 54mhz (Top of 6 meters) NO RESULTS NO CONDITIONS
3rd harmonic 88mhz (bottom edge of FM Broadcast) GOOD RESULTS
4th harmonic 108mhz (Top end of FM broadcast. Start of Aviation band) GOOD RESULTS
5th harmonic 135mhz (Top of Aviation band) FAIR RESULTS
6th harmonic 162mhz (NOAA Weather Radio area of the dial) GOOD RESULTS up to 50 miles
7th harmonic 189mhz NOT TESTED
8th harmonic 216mhz NOT TESTED
10th harmonic 270mhz (Mil Satcom but not a good idea to use cb antenna for this) NOT TESTED
I do not think this would work using a high quality CB antenna. It may work on a low end cheapo like mine
Its worth a shot if you do have a cb antenna laying around to get ya started scanning CB to VHF.
Post your results.
Edit: May I add that I am using RTL-SDR NESDRSmart and HDSDR for the receiver in this test. Your mileage WILL vary!
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