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Cecil Moore wrote in message ...
Mark Keith wrote: How many others feed theirs this way? I don't know and don't much care. The discussion is about your antenna Vs mine. Well, maybe at this point, but not previously. I have had no idea what you do to your antenna. I'm talking about G5RV's in general. Mainly the goofy storebought versions. How would I know how yours would vary from the "usual G5RV"? By the length of the series section transformer. It varies from 20 ft on 10.125 MHz to 35 ft on 18.14 MHz providing less than 2:1 SWR on the coax on all HF bands - no tuner required. On 3.8 MHz with a series section length of 23 ft, the series section feedpoint impedance is resonant at 25+j0 ohms. You missed the question...How would I know you do that unless you tell me in advance...I'm not a mind reader... Because I DO notice the difference between a coax fed dipole and either a G5RV or the usual "windom" that is sold by "eastern state antenna co. inc" Theirs are not optimumized - mine is. Why don't you compare your dipole to an Isotron so you can feel even better. :-) I have. Gives me a woody.... ![]() everything on 80m. So far, it's never lost a race. To anything. Only slightly improved by converting to a turnstile maybe...:/ Other than my ground loss, which will be the same for either types of antennas, for all practical purposes I have no loss. I can say exactly the same thing. My 50 ohm SWR is less than 2:1 without a tuner of any kind. There's simply no places for losses to occur. You can not detect .4 db difference in the real world on 80m. So if my antenna is within .4 dB of yours, it's as good as yours? Yes. IF...But I will still prefer the coax fed dipole. I wish I had said that. As a matter of fact, the difference between your antenna and mine is the difference between an SWR of 1:1 and an SWR of 2:1 on 75m. The ARRL Handbook loss chart says that is 0.12 dB difference for 100 ft of RG-213 on 75m. Now, Cecil, do the math. There it is in the paragraph above. My dipole is 102 ft long. EZNEC sez it has a maximum gain of 6.04 dBi compared to 6.24 dBi for your dipole. Including the 0.2 dB reduction in gain and the 0.12 dB of additional losses in the coax for an SWR of 2:1, that's 0.32 dB modeled difference between your dipole and my G5RV and you say one cannot detect a 0.4 dB difference. Doesn't that shoot your own argument down? No. Your antenna is different than the vast majority used if what you say is true. How many db difference does it take to measure 2 s units on the average radio? A lot more that .4 db, I can tell you. I'll bet $100 that your antenna is NOT anywhere near 2 S-units better than mine on 3.8 MHz. And I'll bet my antenna is 2 S-units better than your coax fed 80m dipole on most bands between 40m and 10m where it functions as well or better than it does on 75m. If you have improved yours, I'm glad. You may well have a decent antenna. But you need to spread the word, because most other's that are unmodified are still gonna be lame radiators. What proposal do you offer to correct the feedline deficiencies of the average storebought windom, or OCF dipole on 40 and 80m? They need your help too. If you all get your heads together, you might be able give me some rf competition this year... ![]() |