Hi Bryan, the only change to 55G sections over the past 30 years or so (in my recollection) is the Z brace bending radius has increased. This is most likely a change to make the Z bracing more resist
John, if you have a 24 to 30v (not ctritical) transformer and a motor starting capacitor you can "rig" a testing circuit. Start with the brake terminals (1 and 2 IRC) and listen for a loud clunk when
Hi y'all, the receive side of the coax loss is not nearly as bad as the transmit side. This is because of all the back ground noise on the HF bands. The noise from the heavens alone is on the order o
Jim, the example compares 200ft of LMR400 to RG213. The stated difference is .358 dB/100ft for a total of .716 dB. That is a power ratio of 1.179 or 100w vs 117.9w. That is easily measured with a bir
Hi All, this is an observation from an innocent bystander: With constant power level, if the antenna Z increases, The voltage increases as well, right? Conservation of energy then requires the curren
Hi All, at the risk of really showing some ignorance, a question: If the choke is doing a good job and located at the feedpoint, isn't the common mode circuit quite short? Seems that the common mode
Hi Ian and others: Is common mode current the same as rf current flowing on the coax shield because it is connected to one half of the antenna? If so, no wonder the feed point is unbalanced; there ar
Your local bearing supplier is your friend. They can furnish any available size in quick turn around. If machining is needed (unlikely with all the parts and options available) they can provide that
Hello All, does anyone know what size conductors are needed for a 500ft cable used with a G1000SDX rotator? Yaesu simply says use #18 if over 125ft. Thanks/73, Gerald K5GW ___________________________
Hi All, running this problem through a mast calculator program shows a wind survival of 93 mph with the following assumptions: 1.9" OD .145" wall water pipe yield strength of pipe 27ksi pipe length 4
Hi Tom, before giving up on the existing motor, you might try to revive it. If you can rotate the motor shaft by hand, it highly likely something is wrong with the start circuit. These motors have se
Hi Rudy, 6061-T6 aluminum has a yield strength rating the same as 6063-T832 that is sold by Texas Towers and others. The 6061-T6 costs more than 6063-T832 because of the extra heating/quenching steps
Jonathan, this sounds like a recipe for disaster! 300 to 500 pounds of force is one matter; making sure you don't exceed that with a vehicle is another matter. I have seen no 500 pound fuses. Another
Hi Steve, with a vswr as low as 2:1 it would be tempting to match it right in the 50 ohm feed line with a stub match. For example. starting with 37R +j0, 40 degrees down the line the impedance is 49.
Wayne, have you done a stress analysis of the stinger? You should be able to use one of the yagi stress programs to do that. If you think about it, your 44ft stinger is similar to one half of an 88ft
Larry, your excellent results suggest that you have already solved the "desert radial" problem! On the unworkable 80m feed problem, that is easily solved by use of a parallel tuned circuit from the b
Hi All, the round trip time for EME signals is about 2 1/2 seconds so it is easy to determine the path. 73, Gerald K5GW eme active on 6m, 2m, 70cm, 23cm, 13cm, 9cm, 6cm and 3cm; something is constant
Hi Tonno, very impressive results! You may not be aware of the galactic noise arriving from various sources in the heavens. The amplitude of these noise sources vary quite a bit from day to day as th
Hi All, eme doppler shift varies directly with frequency. Maximum at 21MHz is + 58 Hz at moon rise and -58 Hz at moon set for latitudes near the equator and virually 0 Hz at the poles The majority of
Hi Tim, I will check out the date and elevation angles on both ends. It may well be that the angles are not compatible for eme. To work, it would have to be approaching moonset for ES5TV and shortly