Scanner for monitoring military aviation frequencies?

originally posted by: DexterRiley
You might be able to build an SDR radio system to listen to aircraft communication.

Apparently it's relatively straightforward to do it for police radios, including trunked systems.

DIY Police Scanner

-dex

SDR is the cheapest, and it might be the best way to go... It can also be hooked up to your phone, you can get creative with a SDR setup, maps, logs, ADS-B, surveillance radar etc.

My favorite handheld scanner is an old AR 8000, hook it up to a vox recorder and it doesn't miss a thing.

originally posted by: imitator

originally posted by: DexterRiley
You might be able to build an SDR radio system to listen to aircraft communication.

Apparently it's relatively straightforward to do it for police radios, including trunked systems.

DIY Police Scanner

-dex

SDR is the cheapest, and it might be the best way to go... It can also be hooked up to your phone, you can get creative with a SDR setup, maps, logs, ADS-B, surveillance radar etc.

My favorite handheld scanner is an old AR 8000, hook it up to a vox recorder and it doesn't miss a thing.

That's what I liked about the SDR solution. It can be integrated into a system to coordinate all of the monitoring activities and record everything in sequence.

They're also relatively cheap these days. The main problem is that it may take a little longer to get everything working right than buying a standard off-the-shelf unit scanner.

-dex

I use the Uniden UBC125XLT when I am up visiting my family in Norfolk or sitting on the approach at RAF Marham. It's a great small receiver for the VHF and UHF bands. Ditched the included antenna though for a better one.

I often listen to the Tornado crews flying around the coast designating targets for simulated paveway drops. Always makes me chuckle thinking there is some little old lady sitting with a cup of tea in the conservatory, unaware that her bungalow has just been designated an enemy mortar position and is about to be obliterated.

You can use this it allows you to listen to frequencies and airports.

www.liveatc.net...

a reply to: dragonridr

It won't do a lot of good sitting in Death Valley though.

Zaph and I had a Uniden Bearcat BC125AT last time we went out to the range. I bought it used off of Ebay for less than $100.

If you want to hear everything, BCD436HP. It can record on a SD card.

For military air, I like the old Pro2042. I have a number of them that I've bought used over the years.

www.lazygranch.com...

I have this,maybe a bit over the top if you only need it for the airband stuff.....

www.icomuk.co.uk...

But don't forget (or maybe you don't know) that a radio is only ever as good as it's aerial.The range on the ground of the VHF airband is only a few miles at the most with the aerial that comes with the scanner.I could JUST about get the controllers at Heathrow (about 40 miles away) with a dipole on a tall mast on the chimney of my old house,where I am now even Gatwick about five miles away isn't full strength with just a loft mounted aerial.
Range also depends on altitude.You can get 200 miles when they're at 30,000 feet or above,but as they descend this range drops to as little as 50 miles or so.This is on the VHF civil airband though,the military UHF airband (225 - 400 MHz) is very strictly line of sight.You will struggle to get anything more than about a mile away on the ground,and maybe 20 miles if you're lucky when airborn.
I have the SDR mentioned previously that gets used at home via my PC,the handheld above still gets used when I visit airports and airshows.

a reply to: FredT

Hi Fred. I use a Uniden BEARCAT XLT125, coupled with a Watson super gain antenna. Covers all civil and military, picks up to about 35 miles and fits in my coat pocket. Highly recommended

originally posted by: waynos
a reply to: FredT

Hi Fred. I use a Uniden BEARCAT XLT125, coupled with a Watson super gain antenna. Covers all civil and military, picks up to about 35 miles and fits in my coat pocket. Highly recommended

Maybe I might treat myself next year with one of those for RIAT just gotta learn how to bloody use the things. I've got some cheap Chinese knock off scanner that I've been using for RIAT that I picked up second hand. Having no manual and not really a clue on how to tune the scanner in took me 5 mins using basic knowledge of it and what frequencies to dial into. I must admit it adds to the fun of an airshow. 2 years back the F-22 had to end its flight short due to an alarm coming up (I think) and I was listening to the pilot and the tower and heard the pilot say he had to end it, few minutes later the commentator on the loud speakers announced it. It's good fun

a reply to: ThePeaceMaker

The Icom one I have is a fantastic price of kit for it's size,but a full numerical keypad makes it a whole easier to enter frequencies and store them in memory and set up exactly which ones you do (or don't) want it so scan.
Also a lot easier when there's a quick frequency change you want to follow.I have to turn a tuning knob several dozen times and could miss it,tap 4 or 5 buttons on a keypad and you'll probably do it quicker than the pilot.

a reply to: Imagewerx

Radar horizon in statute miles equals 1.4 times the square root of the altitude in feet.

originally posted by: gariac
a reply to: Imagewerx

Radar horizon in statute miles equals 1.4 times the square root of the altitude in feet.

Radar is on a higher frequency than comms isn't it,hence an even shorter range? Also the height above ground level of the receiving station (a handheld device) greatly affects range.

originally posted by: Imagewerx

originally posted by: gariac
a reply to: Imagewerx

Radar horizon in statute miles equals 1.4 times the square root of the altitude in feet.

Radar is on a higher frequency than comms isn't it,hence an even shorter range? Also the height above ground level of the receiving station (a handheld device) greatly affects range.

Radar horizon is just a phrase for line of sight communications.

For aircraft, the AGL height of the plane dominates. However you can sum together two stations. Say you have height one (H1) and height two (H2) for station one and station two. Use sqrt() to represent the square root function. Then the
total distance is 1.4*(sqrt(H1)+sqrt(H2))

This is just an approximation. There are more accurate equations. They are all based on the radius of the Earth and simple geometry.

I specified statute miles because there is an equivalent approximation for navy use. They use nautical miles and the fudge factor is 1.23.

originally posted by: waynos
a reply to: FredT

Hi Fred. I use a Uniden BEARCAT XLT125, coupled with a Watson super gain antenna. Covers all civil and military, picks up to about 35 miles and fits in my coat pocket. Highly recommended

Thanks, and thanks to all for all the thoughts and recommendations. I was looking at the Watson antenna an its a Amazon UK only items it seems and not available. This is the 125 avalible here in the US I assume its comparable? www.amazon.com...=sr_1_fkmr0_2?srs=2530687011&ie=UTF8&qid=1509494937&sr=8-2-fkmr0&key words=Uniden+BEARCAT+XLT125

originally posted by: Zaphod58
a reply to: FredT

One of my spotter groups was talking about them the other day. They swear by the Uniden 125XLT. I don't know how well it would work out in the wild, but apparently near a field it works really well.

This seems to be the consensus. Any idea if they upgraded the antenna?

a reply to: FredT

Stock antennas are usually junk. I would get a RH77
forums.radioreference.com...

I hope you know you can't listen to much airfield comms these days without a p25 capable scanner. Certainly not Nellis. The advantage of something like a bc436hp is they use a super narrowband filter on AM since it is already in the scanner for the newer narrowband FM.

Note for DX on milair, you want a first IF in the 700MHz range, which I why I use the old Pro2042 if I'm not using just a 436. Most scanners put the first IF in the milair band which can cause desense.

a reply to: FredT

They didn't say.

a reply to: FredT

Yes, that's the same set. Regarding an antenna, maybe there is a US centric scanner forum that could advise you on that? The standard antenna is reasonable, but an upgrade makes your scanner far more capable.

originally posted by: FredT

originally posted by: Zaphod58
a reply to: FredT

One of my spotter groups was talking about them the other day. They swear by the Uniden 125XLT. I don't know how well it would work out in the wild, but apparently near a field it works really well.

This seems to be the consensus. Any idea if they upgraded the antenna?

Make your own easily enough. A BNC plug (If that's what it uses) and a quarter wavelength whip aerial soldered or crimped into it.At the rough middle of the UHF airband 300 MHz has a wavelength of 1 metre,so the standard 1/4 wave whip aerial will need to be 25cm long.
The claims of gain for aerials like this are rubbish,what is basically a longer aerial wound around a flexible former can't possibly have anything over unity gain.Receiving only aerials aren't as critical for length as they are if you're transmitting through them,but will still work a bit better if they're cut for the band you're listening to.

At least that's how I remember it.Thinking about it some more,have 5/8 wavelength aerials got "gain" over 1/4 wave?