airtraffic

Author Topic: Scanner Question  (Read 5663 times)

Offline Chrizz

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Scanner Question
« on: May 05, 2007, 03:35:29 AM »
I'm only just bought an air band scanner and I've noticed that on some frequencies, I can only hear pilot transmissions.

Is this something I can fix?

Thanks in advance, Chris.



Offline dave

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Re: Scanner Question
« Reply #1 on: May 05, 2007, 08:55:57 AM »
I'm only just bought an air band scanner and I've noticed that on some frequencies, I can only hear pilot transmissions.

Is this something I can fix?

It depends.  You need to find out what facility you are trying to listen to and roughly where (how far away) the transmitter is.  You can pick up pilots in the air easily because you generally have line-of-sight to them.  Ground-based airband transmitters are more difficult to pick up.  First, the antennas are generally no more than 20-100' above ground level.  Second, depending on a number of factors, the transmitter power is typically fairly low. The system is designed for controllers to be able to communicate reliably with pilots - and to minimize co-channel and cross-channel interference.  Setting things up to be able to hear both sides of the conversation is part of the fun and challenge of this hobby.

The facility transmitter you are trying to receive could be a hundred miles away or 25 miles away.  You need to provide more details and we may have folks who can help.

One thing you can consider is an outside antenna if you don't have one already - that always helps but is not a guaranteed path to achieving your goal.

Dave

Offline Chrizz

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Re: Scanner Question
« Reply #2 on: May 05, 2007, 04:33:43 PM »
Well I have two airports about 10 miles away each (not really that far?) with mostly housing and quite flat terrain between us.

The radar and approach frequency that we have here covers both airports, and the hand-held receiver that I have, picks up the pilot side without a problem, however where the controller should be speaking is completely silent. It's probably down to the size of the scanner, I'm not sure about attachments or if adding an additional antenna is even possible. Ideally i'd like to avoid putting an antenna outside, due to the unwanted attention that it would probably attract. Can you put aerials up in your roof-space?

I was recently about four miles from the airport and had no problem picking up the tower and ground transmissions, and then I really did realise that I should have bought a scanner ages ago!!

Thanks for your help so far Dave, it's much appreciated. :)
« Last Edit: May 05, 2007, 04:37:37 PM by Chrizz »

Offline dave

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Re: Scanner Question
« Reply #3 on: May 05, 2007, 04:37:52 PM »
You can definitely put an antenna in your attic...highly recommended as the next step.

Dave

Offline Chrizz

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Re: Scanner Question
« Reply #4 on: May 05, 2007, 04:50:00 PM »
Is this the kind of thing that I'd be looking for?

Would you know if it would be possible to connect that antenna to a hand-held receiver?

(PS. Thanks for the super quick reply!)


Edit: Or maybe something like this for a quick fix.
« Last Edit: May 05, 2007, 04:53:04 PM by Chrizz »

Offline MathFox

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Re: Scanner Question
« Reply #5 on: May 05, 2007, 04:59:42 PM »
Well I have two airports about 10 miles away each (not really that far?) with mostly housing and quite flat terrain between us.

The radar and approach frequency that we have here covers both airports, and the hand-held receiver that I have, picks up the pilot side without a problem, however where the controller should be speaking is completely silent
Do you know where the antennas for approach and radar are located? They can easily be at 50 miles or so from your position. At 10 miles with flat terrain you should be able to hear "ground" with a properly placed antenna.

Offline Chrizz

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Re: Scanner Question
« Reply #6 on: May 05, 2007, 05:03:03 PM »
I know that the radar and approach room are at the airport, and I'm assuming the antenna's are also at the same location, probably on their roof...

Would I be on the right lines or are the broadcast antenna's usually kept elsewhere?

Offline MathFox

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Re: Scanner Question
« Reply #7 on: May 05, 2007, 05:10:14 PM »
I know of several setups where they have receive and transmit antennas at a remote location and use a (telephone) cable to transport the signals from the controller room to the transmitter site.

Offline kiwisteve

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Re: Scanner Question
« Reply #8 on: May 08, 2007, 07:31:46 PM »
Here in NZ  approach and control transmitters are often several kilometres away from the airport or control centre .  They are fed via Microwave links to remote hilltops . So you can't always assume they are at the airfield down here  !! fortunately easy to work out as the transmit licences are viewable on line from our Radio Spectrum Management  agency

Steve