| Author |
Message |
    
Allagator
| | Posted on Monday, December 29, 2003 - 6:12 pm: | 
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OK i went into the trouble of making one now i cant get the swr down past 2.5 any idea's !!!
but i havent had it outside yet !!!!
any help please !!!!!
Allagator |
Mr_Rf
| | Posted on Monday, December 29, 2003 - 11:01 pm: |
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Too much stuff to effect the antenna inside the house...take it outside and try it.
If it still acts up and 2.5 is best, that usually means one side is electrically longer than the other...try foldiug back 1" on one side, check swr, then the other if it went up more. |
Crafter
| | Posted on Tuesday, December 30, 2003 - 12:17 am: |
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Put it in a V or L and see if it changes, also is it highter on 40 than 1 or opposite? |
Stickshift
| | Posted on Tuesday, December 30, 2003 - 5:53 am: |
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Allagator,
I have a dipole mounted inside my shack and it functions very good. The equation for a half-wave dipole is: length (in feet)=468/f (MHz). Take 27.205 (ch.20) for example. It is equal to 103 inches per side or 17.2 feet total. I have a half-wave dipole in my shack inverted at 90°, set up for 11 meters. It's length is 92 inches per side. I know it is mathematically short, but here are my SWR readings.
Through Rad Shack Cheapie meter. Radio is Emperor TS-5010 @ 15 watts:
ch. 1= 1.4:1
ch. 10= 1.3:1
ch. 20= 1.2:1
ch. 30= 1.2:1
ch. 40= 1.1:1
This time with meter disconnected using radio's internal SWR meter @ 15 watts:
ch. 1= 1.2:1
ch. 10= 1.1:1
ch. 20= 1:1
ch. 30= 1:1
ch. 40= 1:1
I built this thing many years ago and it performs pretty well. I recently inverted at 90° as I mentioned earlier, and have recieved the best results in this configuration. It is very good for dx'ing and works fairly well with local traffic, considering it's mounted in the shack. It is mounted east-west and have talked 45 miles north of my station using a stock Uniden Washington on channel 40 LSB. Granted the conditions were exceptionally well, but it did the job.
This antenna is constructed from 10 foot of RG-58 coax to the center feedpoint, and 12 gauge lamp cord. The shack is probably not the safest place for it, but it works. I use it mostly for monitoring DX, but as I stated earlier it works fairly well for transmiting.
A bit of advise when constructing your dipole. Make sure you cut your wires a bit longer (3 inches or so) for your particular tuning needs. I've found that installing allagator clips on the ends of the wires and pulling the wire back towards the center point and curling the wire around itself is a good way to tune these antennas.
Good luck with your antenna project!
stickshift |
Allagator
| | Posted on Tuesday, December 30, 2003 - 5:24 pm: |
|
hey Stickshift ill try your info and my feed line is rg58 A/U with 20gauge solid copper wire !! i hung it off my dear head useing rope and a egg inslatiors at both ends the other end is hooked to a piece of PVC pipe straped to the comp desk !!! if it will works better after tying your info ill move it out side !!!
Thanks again !
Allagator |
Stickshift
| | Posted on Wednesday, December 31, 2003 - 1:46 pm: |
|
Allagator,
Let me know how you results turn out. Another thing, with my dipole, as I mentioned, I used multi-stranded 12 gauge wire. It works fine indoors. It's nice and flexible. I easily secured my dipole to the wall with white thumb tacks. I've mounted these same types of dipoles to the eves of roofs with a stapple gun. Nice long stapples will secure these antennas fairly well, providing the wood of the eves is good! Once again, I know these aren't the most effective methods of mounting antennas, but I've found them to work fairly well. Keep us posted with your results!
73's
stickshift |
Allagator
| | Posted on Friday, January 02, 2004 - 5:45 pm: |
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Hey Stickshift Guess what i used your info and wammp it works like a DREAM so i took some PVC 2-8foot peice's 1/2 pipe and a good PVC T and mounted it to another peice of PVC about 4 foot and hooked it to a rotor HEHEHE !!!!
the feed line runs inside of the 4 foot peice then it splits both end's of the wire's is glued to a peice of rope and pulled tight then the rope was glued inside the pipe !!! i caped the ends and now i have me a new TOY !!!!!
THANKS FOR THE INFO STICKSHIFT IT WORK'S LOL
ALLAGATOR |
Stickshift
| | Posted on Saturday, January 03, 2004 - 12:25 am: |
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Alagator,
Glad to hear that all is working well with your antenna system! Sounds like your work has paid off. You'll have fun working stations with that little dipole! 
73's
stickshift |
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