Hi John,
Per your suggestion, I ran a sweep of my 40 meter vertical with the K3 / K3EZ software. I then measured at ~20 kHz steps with my MFJ-259B. Both sets of measurements were taken from the PL-259 that plugs into the rig or 259B. Conditions were ~60 degrees F, ground nearly saturated. Attached is an image of the results. Kindly, Dick - KA5KKT ---------------------------------------------------------------------------- ----------- Hi Dick, An EZNEC and SimSmith model of the on ground 1/4 wave vertical: https://www.kn5l.net/images/SS-KA5KKT-vertical.png SimSmith R1 represents ground loss, the value set to establish a 50 ohm load at the transmitter, G in SimSmith. According to the models, the 7 to 7.3 MHz SWR is a little below 1.3. A flat measurement using the K3 SWR meter seams reasonable. My suggestion is to use a Antenna Analyzer to measure the antenna and system. John KN5L On 12/2/18 12:16 AM, Dick Dickinson wrote: > I have a full-size monoband vertical for 40 meters. Simple > architectural aluminum tapering from 1 ¼ (?) in 6 telescoping > sections. The radial field is designed to provide a 50 ohm match at > the feed point 12 13+ radials. It is fed directly no matching > device with RG-213 from the remote antenna switch about 50 away at my > tower. The coax from the rig to the remote antenna switch is > estimated to be ~ 50 in length. A lot of the time running K3EZ to > sweep the band (typically 20 watts), it will indicate a > 1.0:1 SWR from 7.0 MHz to 7.3 MHz in 20 kHz steps. Occasional > deviation from one K3EZ run to another might be due to variations in > moisture content of the ground or less than perfect connection to the > vertical an uncommon situation. The K3 shows the same readings. > > Is this 1.0:1 SWR across the entire 40 meter band curious or remarkable?
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