Author Topic: HF Feed Listening  (Read 13626 times)

Offline wb2uzr

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HF Feed Listening
« on: March 06, 2014, 04:47:43 PM »
Hi All:
Just wondering what the best listening plan for the HF feeds would be as far as catching the busiest frequencies. I know about nighttime vs daytime propagation, but just curious what feeds would be best as far as traffic volume vs time of day?

Thanks!

Scott/WB2UZR



Offline InterpreDemon

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Re: HF Feed Listening
« Reply #1 on: March 06, 2014, 05:19:01 PM »
During the day the 8 & up is busier, night below. ARINC is pretty good about changing bands to maintain good S/N, so unless a feed Rx is in a skip zone the signals are strong if they are in use. The NAT-E coming out of the Azores is pretty good at night, as is the CWP feed. It's really a matter of listening comfort and patience, some of the feeds use higher gain and AGC than is required, IMO, because as I said before, when a band is in use the signals are pretty strong, so listening to hours of high amplitude static between transmissions is not the kind of thing I personally prefer unless contesting.

The new USAF feed has been getting some big spikes in listening traffic, doubtless folks trying to decode the meaning behind the cryptic transmissions and EAM's. To me that is about as interesting as listening to a numbers station, but the equipment he is using is excellent and the quality pretty good.

My own feed, CAR-A 6557/5550, is pretty much manned and tweaked around the clock. I use two R-390's coupled in diversity mode feeding a CV-157 converter, meaning I am always receiving two frequencies at once (the primary and back-up in use at any given time among seven or eight frequencies from 2.887 up to 17.907), so it's pretty much always busy with the Caribbean traffic in the New York FIR.

One easy way to find out current HF frequencies in use over the Atlantic is to tune in the KJFK ARINC VHF 129.9 feed, where aircraft transitioning from ZNY and ZBW high sectors on VHF check in with ARINC to make their initial position reports and receive HF frequency assignments, which occurs at about 250mi out to sea. That VHF feed is also multiplexed into my HF LDOC 6640/8933 feed (along with some other rarely used exotic VHF frequencies) for one-stop listening of frequency assignments, SelCal checks and phone patches.
« Last Edit: March 06, 2014, 05:32:34 PM by InterpreDemon »

Offline wb2uzr

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Re: HF Feed Listening
« Reply #2 on: March 07, 2014, 10:41:43 AM »
Thanks for the info!


Offline alphazulu

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Re: HF Feed Listening
« Reply #3 on: March 07, 2014, 11:05:28 AM »
Concur, Thanks InterpreDemon!

Offline InterpreDemon

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Re: HF Feed Listening
« Reply #4 on: March 10, 2014, 09:54:34 PM »
I just found what I think is the best aeronautical HF frequency listing yet:

http://monitor-post.blogspot.com/p/this-international-hf-aero-frequency.html

Offline Squawk 7700

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Re: HF Feed Listening
« Reply #5 on: March 11, 2014, 12:37:51 AM »
Great find InterpreDemon!
You're getting me interested in HF monitoring again! :-D

Offline InterpreDemon

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Re: HF Feed Listening
« Reply #6 on: March 11, 2014, 01:31:27 AM »
Well... we could use a nice feed out of KSFO to cover the East Pacific :-) You can use one of those little $20 SDR/TV dongles and a $50 up-converter (converts HF frequency up to VHF where the dongle can tune it in) along with some cheap, home-made band pass filters and get one on the air.

For VHF, you could add 131.95 to get the ARINC HF frequency assignments leaving the West Coast. Main thing for HF is to have a good location near the ground station(s) so whatever frequency they are using works for you too and, as I said before, keep the gain down with minimal AGC action so that the feed is comfortable to listen to.

Offline InterpreDemon

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Re: HF Feed Listening
« Reply #7 on: March 14, 2014, 09:58:50 PM »
Was tuning the secondary receiver around on the 6577/5550 feed tonight and managed to catch Air Canada 087, flying the polar route from Toronto to Shanghai, over the West Siberian Sea talking to Russian controllers (RDARA, probably Magadan) on 11390. You can find it in the 6577/5550 archive for March 15, 2014 @ 01:30Z, QSOs start at around 01:40Z

I left it dialed in for a while during the band opening, 5550 traffic with NY steps on it occasionally. Other flights flying the 15hr route (UAL895 ORD/HKG, etc.) heard as well.

Position of AC87 at the time attached. Not bad for almost half way around the world, orientation of my antenna makes this possible from time to time.
« Last Edit: March 14, 2014, 10:29:26 PM by InterpreDemon »

Offline dave

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Re: HF Feed Listening
« Reply #8 on: March 15, 2014, 09:16:46 AM »
Very cool catch.  That polar path is open pretty often near 7MHz from the Eastern USA.  Love that polar flutter!  If you listen for a little while you can also hear Over-the-Horizon (OTH) radar - for those who never heard it, it sounds a little like a woodpecker.

Offline JetScan1

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Re: HF Feed Listening
« Reply #9 on: March 15, 2014, 10:57:25 AM »
Nice catch ! I've heard aircraft working Magadan before but never so far into Russian airspace. Interesting that they are not using CPDLC on that route. To far north for satellite coverage or it wasn't working that day ?

At 08:40 on the 0130Z archive Air Canada 087 gives a position report to Magadan at waypoint UNTEK at time 013?Z at FL320 eta waypoint NIGES at 0214Z with waypoint RANEN next. Then at 13:46 on the 0200Z archive you can hear them calling Magadan to give the position report at NIGES and they get handed off to Tiksi Control on VHF 129.50.

(The distance from waypoint UNTEK to your general location is around 3500 nautical miles, and from waypoint NIGES around 3800 nautical miles, you can see the route using Skyvector).

I also noticed at 01:27 on the same 0130Z archive that you picked up Springbok 204 (South African Airways, JFK-JNB) making their initial call to Luanda over position GAPEL. Most of the transmission after that are blocked by New York traffic. Okay reception of Luanda, what frequency did you catch that on ?

(GAPEL is around 5000 nautical miles from you location, and Luanda 5600 nautical miles).  

« Last Edit: March 15, 2014, 11:09:18 AM by JetScan1 »

Offline InterpreDemon

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Re: HF Feed Listening
« Reply #10 on: March 15, 2014, 12:46:49 PM »
That Springbok/Luanda was either on 2878 or 5493... I was actually trying to look for NAT-I & J signals out of Shanwick on those two bands at the time and stumbled across it. Ever since I trapped out my antenna I don't get the lower ("near MF") bands as well since I also shortened it and it's lowest resonance is at 5.5, so I am thinking about just leaving the traps for 6.5 and 8.8 and extending the ends again to get the low stuff overnight.

Also thinking about an experimental higher bandwidth HFDL feed since I get some of that pretty well. Wonder if a 24 kHz stream could be decoded. Trick would be for a way for somebody to couple the stream audio to their decoder/plotter without using two computers... Dave?
« Last Edit: March 15, 2014, 12:55:37 PM by InterpreDemon »

Offline dave

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Re: HF Feed Listening
« Reply #11 on: March 17, 2014, 06:53:24 AM »
That Springbok/Luanda was either on 2878 or 5493... I was actually trying to look for NAT-I & J signals out of Shanwick on those two bands at the time and stumbled across it. Ever since I trapped out my antenna I don't get the lower ("near MF") bands as well since I also shortened it and it's lowest resonance is at 5.5, so I am thinking about just leaving the traps for 6.5 and 8.8 and extending the ends again to get the low stuff overnight.

Also thinking about an experimental higher bandwidth HFDL feed since I get some of that pretty well. Wonder if a 24 kHz stream could be decoded. Trick would be for a way for somebody to couple the stream audio to their decoder/plotter without using two computers... Dave?

Very possible…just that all the decoders out there seem to be ported only to Windows.  So theoretically we could bring up and devote a machine to that, but not sure how much interest there would be.

A good friend runs a site called DXflights.com - has a couple mobile apps that allow following flights tracked by HFDL only.

More info: http://dxflights.com

You may want to drop him a line at info@dxflights.com if you want to send a feed over…but I'm pretty sure in his case all decoding is done prior to sending, not on the server side via audio decoding off a feed.