I have erected a steel rod dipole for airband reception at about 15 feet high cut to frequency, run the lead down the wall and into house, but so much static on receive drowns out speech. Any ideas on what could be the problem. I am new to this hobby so not into the technical aspects.
Airband
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Ubbe
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How is the reception compared to an antenna connected directly to the scanner? You could be located in a bad area that are too far away from aircrafts. AM has lots of static if the signal isn't strong enough. My VHF aircraft reception have half the signal drowned in noise 90% of the time.
The antenna have one element connected to the inner lead of the coax and the other element to the braid and no short circuit between them?
/Ubbe
The antenna have one element connected to the inner lead of the coax and the other element to the braid and no short circuit between them?
/Ubbe
N1EXA
FT8 Huntin Mudd Duck on the deep end of the pond !
Is this Dipole Vertical or Horizontal and what's the Length of each side?
What's the distance to your airport you listening to and can you get the ATIS?
What Radio are you using ?
Pete N1EXA
What's the distance to your airport you listening to and can you get the ATIS?
What Radio are you using ?
Pete N1EXA
An FM broadcast filter may be able to greatly improve your reception on an outside antenna.
Thanks for the replies. My radio is a Yaesu ft-70. My dipole is vertical and is cut to around 23" per element. Distance to nearest airfield is around 10 miles, no ground radio heard, but some aircraft heard.
Reception with the supplied antenna not good, but have an after market version which is better, but the signal from the dipole is a lot better but full of static.
Reception with the supplied antenna not good, but have an after market version which is better, but the signal from the dipole is a lot better but full of static.
Aircraft and control tower radios are low powered. Therefore, depending on terrain, range will be limited. This is not a problem because aircraft communications tend to be line of sight. However, ground control and tower frequencies can be difficult to hear at 10 miles. Have you tried approach and departure frequencies? These tend to be much easier to hear. Check airnav.com for the frequencies in your area.
Vertical dipole questions come up in these threads frequently. They seem very simple to build, but can be problematical. For aircraft reception they are not very broadband for a spectrum that is 18MHz wide. Any dipole is a balanced load. That is, feeding it directly with coax is going to be less than optimal. A 1:1 balun is needed. Some use ferrite chokes or coils of coax at the feed point. These are not recommended. The feed line should run at right angles to the antenna for a quarter wavelength to avoid interaction with the antenna. The antenna should be mounted free of obstructions.
Having said all that: A discone is a better choice for monitoring air frequencies. It is broadband and can be fed directly with coax. It will also cover military aircraft frequencies. No they do not have any gain. However, the flat frequency response is more important. Remember that you are mostly hearing line of sight transmissions anyway.
Vertical dipole questions come up in these threads frequently. They seem very simple to build, but can be problematical. For aircraft reception they are not very broadband for a spectrum that is 18MHz wide. Any dipole is a balanced load. That is, feeding it directly with coax is going to be less than optimal. A 1:1 balun is needed. Some use ferrite chokes or coils of coax at the feed point. These are not recommended. The feed line should run at right angles to the antenna for a quarter wavelength to avoid interaction with the antenna. The antenna should be mounted free of obstructions.
Having said all that: A discone is a better choice for monitoring air frequencies. It is broadband and can be fed directly with coax. It will also cover military aircraft frequencies. No they do not have any gain. However, the flat frequency response is more important. Remember that you are mostly hearing line of sight transmissions anyway.
Apparently you're into making your own antenna... so try this one. Inexpensive, simple to make, and according to nearly all reports here on RR... works well on both the civil and military air bands -
Homebrewed Off-Center Fed Dipole - The RadioReference Wiki
Homebrewed Off-Center Fed Dipole - The RadioReference Wiki
How far away are FM broadcast stations? If nearby, they could cause desense, especially on VHF aviation freqs.
Nearest fm station is about 15 miles away. I did notice that when I swivelled the dipole the other day through about 90 degrees reception cleared slightly, but then the following day static returned. I think I must be in a really bad spot. My previous house was a lot higher elevation and reception was better with just a dipole in the loft.
spanky15805
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Poweline noise from 118 to roughly 128 and trying to get the local power company to even acknowledge their lines could be a problem...good luck! Don't laugh too hard at the next one...wireless mice are brutal! What type of LED lights are you running? Fluorescent lights? Just a few of the radiators I've tracked down in the past 6 months
What are you using for your antenna feed line?
spanky15805
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dogbot...
don't forget Homepage | NOAA / NWS Space Weather Prediction Center
It does effect the noise floor.
don't forget Homepage | NOAA / NWS Space Weather Prediction Center
It does effect the noise floor.
LED lights with a dimmer switch play havoc on VHF AM airband. I know this from direct experience. Especially if it comes and goes. It can be four or five houses away as in my experience. I knew the residents and they worked with me. When they sold the house, I hired an electrician and we replaced the dimmer switches before the new owners moved in.
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