40 MHz Homebrew

[topgun1986]

I would like to make an antenna for the 37 MHz to 45MHz range. It will be for receive only going to one of my Pro 82 scanners. I believe the National Guard & American Red Cross are in that range but unsure of exact frequencies for my location. Or perhaps someone knows a good antenna that is just easier and cheaper to buy.

 

[AronDouglas]

I use this for ideas. The plans are not meant for the frequencies you need but thats a matter of simply changing the element lengths.

http://files.radioscanner.ru/files/download/file311/practical_antenna_design.pdf

 

[k9rzz]

Or just make a wire dipole (Google it). 468/mhz = length in feet. Cut it for the middle of your frequency range and don't sweat it any further. Hang it vertically and as high as you can. Use the best coax you can but if you can't afford the top of the line, again, don't sweat it, use what you can. Just get the basics and don't go crazy over details. :^)

 

[topgun1986]

Thanks for tips fellas. I found an online inverted vee dipole calculator, via Ham Universe. I've never built a dipole so I think I am gonna go for it.
For 41MHZ, the design looks like a fairly small space is required outside. Now I get to "engineer" a new home brew antenna. I'm thinking I will use some insulated #12 copper wire for each leg and make some insulators out of 1" PVC down at my work bench.

Since it will be for RX and not TX, I'm not sure which feed line I should use for better results. All I have on hand for now is some leftover RG6QS coax and some 300 Ohm Twin lead from Radio Shack. Antenna will be roughly 80' from my scanner so I may just try both.

 

[majoco]

See if you can get a used channel 2 TV antenna and strip off all the unnecessary bits - all you need are the longest elements - a perfectionist would lengthen them slightly. I often do things like that to 're-purpose' things. Pic here....

http://forums.radioreference.com/scanner-receiver-antennas/298707-diamond-d220-discone-antenna.html


right at the end of the topic is of a modified TV antenna for airband, 220mHz and 400MHz bands.