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Mark, I agree with you on the dipole but expand on it a bit. Build a fan
dipole. "Mark Keith" wrote in message om... "JEFF UK" wrote in message ... Just wondering........... What would be best for my next receiving antenna. 1) A long wire , coax feed (no balun ) about 80 feet, ( earthed coax braid) 15mtrs from house. or 2) A Long dipole, about 80 feet each side. Noisy here at times. What do you reckon? Best Regards Jeff I'd rather have the dipole I think, but it really doesn't have to be that large to work well. Would be nice for the lower bands though. Overall, the dipole will probably give you the best s/n ratios being it's usually fairly easy to decouple. I'd use a good 1:1 balun or a coax choke or ferrite beads. If you used a 160 ft 1/2 wave dipole, it would be resonant at 5.8 mhz as a half wave. 11.6 mhz as two half waves in phase which is a hi-z feed. About 17.4 mhz as a 1.5 wl dipole, which is a low Z feed. Other bands will vary... It would work pretty well on most all the higher bands. The pattern on the upper hf bands would be multi lobed, and fairly omnidirectional overall. The mismatch using coax to feed one of these is not worth worrying about for receiving. The coax loss on any HF band is not enough to lower the s/n ratio. Not even close unless you have a dead radio or dead coax. All bands will still have plenty of signal level. But you could use twin lead and a tuner if you were worried about feedline loss. Another advantage to the dipole, is you then really have three antennas. The dipole fed normally. Or you could feed one conducter, "usually the center pin, by unscrewing the shield and letting ground float" as a random wire. Or you can tie the center pin to shield at the shack , and feed as a single conductor T vertical. Good for 160m, MW, LW, etc..Myself, I parallel dipoles on the same feedline. Right now, I have a 80m turnstile, and a 40 dipole on the same coax feed. It's a good SWL antenna anywhere in the HF spectrum. Sometimes I have 80/40/20. Sometimes 160/80/40. Just depends on the time of the year, and what I'm working the most. I didn't use a 160 dipole this year, as I usually prefer my top loaded vertical. MK |
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