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Showing content with the highest reputation on 05/11/20 in Posts

  1. I just ordered a Yaesu FTM-7250DR Dual Band radio, base antenna, p/s, cord and LM240 coax today from Universal Radio. After a ton of research on the Internet this radio seemed like a good starter setup. I should get my call sign today or tomorrow. For an HT I will eventually get something like the Yaesu FT-65R.
    1 point
  2. Ok. First off. I do not know how to property test Ht antennas. A calibration was done with the SMA extension for each frequency band when changed. All antennas are authentic from what I can tell. The Nagoya's are from Btech and the Abree is from Abree. Nagoya 701c 144.000 1:1.38 146.460 1:1.15 147.999 1:1.32 420.000 1:2.06 450.000 1:2.21 462.5625 1:2.15 467.7250 1:2.13 Nagoya 771 144.000 1:1.23 147.999 1:1.50 420.000 1:1.55 450.000 1:1.14 462.5625 1:1.37 467.7250 1:1.45 Abree 42" 144.000 1:1.55 147.999 1:2.02 420.000 1:1.55 450.000 1:1.84 462.5625 1:2.24 467.7250 1:2.38 There was a big difference between holding the coil of the antenna(base) and the lead. Unfortunately, it isn't like an MFJ analyzer where I could screw it into. So I chose to hold them by the coil except for the Abree. Holding the Abree by the coil it would go from 1:1.55 and then jump to 1:6.63. Even laying the antennas on the table it would jump by quite a bit. Try holding a 42" antenna by the SMA lug, my fingers hurt.. Again take this with a grain of salt. Should add, for GMRS the 701c is the one I would go with. The 771 works but I perfer the 701c. The Abree rocks for 2m.
    1 point
  3. I think this thread has run its course.
    1 point
  4. kidphc

    Antenna Theory

    Low swr is better. 1:1 means you are getting all the power out. Higher means you are getting reflected power or wasting some as heat. There is an old video (50's 60's) that explains it with models. Swr is not the end all to antennas and many focus on it too much. But generally strive for lower. Db is the increase of gain on the antenna. Dbi means it is based off a reference. Usually DBi gives you a better idea of increase in gain to a reference antenna. Where db may the gain vs a pencil for all you know. So 3 db with make your 5 watt radio equal to a radio with 15 watts of power with no gain. The higher the gain value normally the radiation pattern is flatter with a higher take off angle. For example 1/4 wave antenna is a bit more spherical (like a ball). So when offroading it can be beneficial if you are going up a dune at the crest and there is a truck below you, you'll can hear him. With a half wave design the pattern is flatter and you may not hear him. However, when using a repeater from a mobile the 1/2 wave can more beneficial because then repeater is higher and you have more gain. Sent from my SM-G975U using Tapatalk
    1 point
  5. Sigh... wasn't letting me add the JPG. https://i.imgur.com/mVih2uV.jpg
    1 point
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