Just tried making a 40m quarterwave dipole. same thing. no match. I shortened it 5% and still absolutly no match. No swr dips across the band. Its almost as if the antenna isn't there except I got the usual s7 neighborhood noise and can hear a few BC and ssb stations. I ran all day today on 17m with no issues so I don't think its my coax or mount. I am totally stumped on this... i mean really competely and totally stumped. I am at the end of my rope. I can't figure out what else to check.
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I (we) still are confused with your description. A dipole is normally considered a half wave.
"Where would we be without the agitators of the world to attach the electrodes
of knowledge to the nipples of ignorance?" ~ Professor "Dick" Soloman
Well I asked that earlier and didnt get an answer so i tried making a quarter wave. So I guess thats not gonna work. OK I got that part down. I don't have enough horizontal or vertical height to make a 40m halfwave dipole then so that idea is out. Now one thing I DID notice is that there is a close resonance at 14.7 20m so that puts me back in the same boat I was in before making a 20m dipole. The math puts them only 3 inches apart. 196 inches for 40m vs 199 inches for 20m dipole. I'll give it a shot tmomrrow to see if I can get this one to match on 20. It was 2.5 at 14.7mhz at its lowest dip according to the mfj259. I ran into the same thing when I was making the first 20m dipole that didnt work. Maybe I can figure this one out
Last edited by W5BRM; 10-21-2014 at 05:27 PM.
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"Where would we be without the agitators of the world to attach the electrodes
of knowledge to the nipples of ignorance?" ~ Professor "Dick" Soloman
"I don't have enough horizontal or vertical height to make a 40m halfwave dipole then so that idea is out."
Horizontal height? Oh man, you sure ARE disorganized! (;->) But who said a dipole has to be straight? I knew a guy with a postage stamp lot and a 160M dipole in the back yard, looked like a copper spider on LSD had at it but it worked. When I lived in West Creek, Phil K2PG had a 160M sloping V in his back yard with the far ends running down two small sections of tower to the ground, it didn't work. Using two small trees for end support I bent the ends toward each other about ten feet apart, sort of a sloping open delta, then it worked. BTW with a tuner and open wire ladder line it worked well from 160 to 10 including WARC and Army MARS.
Now get out your copper spider and since there hasn't been LSD since Owsley took off into the stratosphere give it a few drops of whiskey and tell it to get busy.
"The universe is under no obligation to make sense to you."
Neil deGrasse Tyson
73 de Warren KB2VXA
Station powered by atomic energy, operator powered by natural gas.
Ok I think my issue has to be my feedline. I put up the 10m dipole last night. Worked fine. Had a 1.3swr at 28.076. Had 1.6 at 28.500 Raised it to 30 ft from 20 ft. Worked Australia and a few stateside stations before conditions went away. Turned radio on this morning. Worked France and England and some local stuff.
Without making a single adjustment to the antenna.. in fact not even going outside, the SWR just went through the roof about 2 hours after my 1st transmit.
Once again, there is only a minor dip from 27.500 to 29.000 via mfj259. This was reflected accurately via the radio swr meter... except for below 28.0. Radio wont xmit there. SWR read 2.9 from 28.0 to 29.0.
Inspected the connections. All tight. Coax screwed in tight. antenna lengths are still in adjustment. No visible breaks anywhere. No kinks in the antenna wire. There is absolutly nothing wrong with the wire or how its hung. that pretty much leaves just the feedline.
Once I get back to work (hopefully this Monday) I will see about getting a new stretch of coax. Don't have any baluns or anything else so ladderline or balanced line isn't possible at this time. I just don't understand why the coax will work on some bands and not others if it is indeed broken somewhere inside.
I'm also looking at the MFJ window passthrough for coax and balanced feedline but thats gonna be a bit down the road.
Anyway, I'm done for the weekend and longer if I do get back to work. If I don't get back to work, then i'm sunk as I don't have $$$ for a new stretch of coax.
It sucks being poor on medical leave...lol
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Yellowtail, skipjack, or bluefin???Originally Posted by KG4NEL
Encrypt everything. Even if you have nothing to hide. It increases the noise floor.
Why does every one of your antenna projects end in disaster? Antennas are one of my specialties (more or less) but frankly I've run out of ideas. I'd like to invite you over for a cold 807 but I live in mortal fear of you. (;->)
"The universe is under no obligation to make sense to you."
Neil deGrasse Tyson
73 de Warren KB2VXA
Station powered by atomic energy, operator powered by natural gas.
One thing I noticed in a photo that was posted, was a wad of the shield just kind of hanging out of the PL259. If that is the way it was done, that is a sure fire place to have an intermittent connection. When it is not making a good electrical connection between the connector and the shield, you are losing one half of your dipole/vee. As RF passes, heat will be generated and can further cause the connection to come and go. If it were me, I would redo the coax connections at each connector insuring proper electrical connection. There are a number of helpful sites on the internet demonstrating the best way to connectorize the coax. I think this would be the first thing to do eliminate the coax/connector situation as a source of trouble.
A clear conscience is usually a sign of a bad memory
RIP ALBI-W3MIV RIP RUSS-W5RB RIP BOB-VK3ZL
Lol the 12 and 17m turned out fine so not ALL of them were disasters. The 10m i dont know what happened. It changed by itself with no interaction from me. As i said i then i think its the coax. Gonna hv to redo the coax connector. Been planning on that anyway. If i get back to work ( which i doubt... In dr office as i type this) i plan on getting new preassembled coax. My solder skills suck.
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