| Author |
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watchman
| | Posted on Tuesday, June 19, 2001 - 10:10 pm: | 
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Hey "307" or any one out there got any info on homebrew linears & antennas? I'm at the last section of my tech. license for ham ops. and was interested in making some homebrew projects myself but cannot find any help. Any clues as to where I can pick up info. on this would be greatly appreciated...
Thanx for all the insight
"Watchman" Tenn. |
FirebirdTN
| | Posted on Wednesday, June 20, 2001 - 8:09 am: |
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Hey Watchman-
I just got thru building 3 140 Watt footwarmers. check out www.communication-concepts.com. If you have some technical background, and you bother to read (and understand) all the info in those Motorolla Engineering bulletins, you can build any size you want. Literally from milliwatts to Kilowatts.
The particular project I built was the "EB-63". Works great. Good signal reports. There were a couple mods I did to the circuit, but they work just fine. I put a "pad" in the circuit so I didn't have to turn down a stock radio. When I did that, it did reduce the power out somewhat, but without the pad, a 4 watt radio would overdrive the amp in AM.
Without the pad, I experimented and got power levels over 200 watts!
By the way, I am in Memphis, but grew up in Clarksville. |
watchman
| | Posted on Wednesday, June 20, 2001 - 10:31 pm: |
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Cool, hey appreciate the info firebird I dont have really any electronics expierence but been reading a couple of books I got from the library, Discovering elec. and first steps in radio projects, maybe they'll help a little. Any ways thanx for the info....Im in Cookville Tn. about half way between Nashville and Knoxville
Anyone else w/ more info on home-brew stuff would be greatly appreciated.. thanx again firebird."73"'s "Watchman"Tenn. |
CQDX181
| | Posted on Sunday, June 24, 2001 - 1:31 pm: |
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All,
I have designed a home brew, 1/4 wave ground plane, VHF antenna for scanner recieve. Works awesome for the 2 meter band up to the 155 MHz police band and weather freqs. This antenna can be made for less than $5 bucks, and can be mounted anywhere.
I will post the plans in the near future.
Steve
181 |
Watchman
| | Posted on Sunday, June 24, 2001 - 6:24 pm: |
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Hey cool would like to definitely like to see those plans on the ground plane VHF scanner antenna.Will be looking forward to seeing those...Much appreciated CQDX181...."73's"
"Watchman" Tenn
Also anyone else out there with home brew projects please leave any cool info and plans you have..it will benifit us all...Thanx |
CQDX181
| | Posted on Monday, June 25, 2001 - 3:46 pm: |
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Anyone who wants a .ZIP file with the VHF 1/4 Wave Ground Plane antenna plans, instructions, and images, can E-Mail me at CQDX181@aol.com
Steve
181 |
Anonymous
| | Posted on Wednesday, August 01, 2001 - 3:04 am: |
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a v-beam antenna has lots of gain abt 11db and is easy to build.
2 pieces of wire 8 wave lengths long with a 35 degree apex angle. feed it with a 12:1 balun and coax. 38 feet above the ground works good on 20 meters. |
707
| | Posted on Wednesday, August 01, 2001 - 3:58 pm: |
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if you have lots of room, you can try a Rhombic antenna. 5 wavelengths or more, long wire antenna in a diamond shape, with a 20 degree major lobe around 17dbi gain. Takes lots of room , but is well worth it if you need something to hit a particular direction on a regular basis. Works on all bands. Back in the beginning of TV, it was used a lot on the receiving end. |
bruce
| | Posted on Wednesday, August 01, 2001 - 8:53 pm: |
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707 on uhf i have used them and real big ones have good gain You are also correct they must be several wavelengh long to work . 5 waves on cb would be around 170 foot EACH LEG ! Because of this at CB you would have to rotate the town unless you wanted only one direction. The first Moon bounce was done in the early 50's using one on them. and yes you can stack them for more gain! |
doctor bleedover
| | Posted on Friday, October 05, 2001 - 1:51 pm: |
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the simplest antenna i know of is the inverted "v'. all you need is about 9 feet of wire on each leg of an upside down v shaped antenna.u hook the center of your co-ax to one side and the shield to the other and tie it to a tree limb with fishin' line.the apex of the antenna should be about 90 degrees in order to have a 50 ohm match.make the legs a little long and cut them off a little at a time to get the swr down where you want it. it can be made for any frequency by using the formula : total length = 464 divided by the frequency.
i have one hooked to the rafters in my attic that works well. |
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