136 - 167mhz Signal

Hi
I receive an very narrow (Digital) Signal. Its just ~7khz Wide.
Any idea?

Since you're not in the U.S. I haven't the slightest idea. Maybe ask someone in AT. 73, n9zas

Since you're not in the U.S.

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Sats circle arround the world.

Maybe ask someone in AT.

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Good Joke.

Your_account said:

Sats circle arround the world.Good Joke.

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No joke, since we're in the U.S. and we have Many services in that frequency range using Many different modes and formats. I have no clue what you're describing. Those in your country would have better answers, we're not it. 73, n9zas

gewecke said:

Since you're not in the U.S. I haven't the slightest idea. Maybe ask someone in AT. 73, n9zas

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gewecke said:

No joke, since we're in the U.S. and we have Many services in that frequency range using Many different modes and formats. I have no clue what you're describing. Those in your country would have better answers, we're not it. 73, n9zas

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No where in this forum description does it say it's for the U.S. only. If you aren't going to help then move on.

Your_account said:

Hi
I receive an very narrow (Digital) Signal. Its just ~7khz Wide.
Any idea?

Click to expand...

There are a lot of old satellites in this range that still are sending their downlink signal here even though they are no longer operational. Many years ago I wrote a popular series of books for the radio monitor satellite enthusiasts called "Communications Satellites." I still have a large database of satellite frequencies, including the 136-137 MHz range. Pass along the frequency and I will be more than happy to see if I can find a match and we can go from there.

So would you pass along the frequency. It was not in your original message. I also need to know your location (you might also want to throw in your name), and if you receive the signal constantly or intermittently and how often.

73 de Larry, N5FPW

Hmm I received an Weather Sat and some strange very narrow band Signals.

Without any other details, I can't lock it down to any specific satellites. There is no indication in your graphic to show time hacks, but since I see no Doppler shift and there are "no" geostationary satellites in the 137.231-137.340 MHz range, the signal you illustrate is probably terrestrial and not a satellite. There would only be two candidates in that range, the low earth orbiting Orbcomm sats and the NOAA polar orbing wx sats, neither of which would have a modulation type you show in your screen grabs. Without any additional information, you mystery signals look terrestrial.

73 de Larry

There is no indication in your graphic to show time hacks

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It run very fast. It shows ~20sec.
I can post a Picture with Time because there is also the Airband who is not allowed to tune in.

the signal you illustrate is probably terrestrial and not a satellite

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The Signal comes and go.

Without any additional information

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If you tell me what you want to know I can tell you many things.

Your_account said:

It run very fast. It shows ~20sec.
I can post a Picture with Time because there is also the Airband who is not allowed to tune in.
The Signal comes and go.
If you tell me what you want to know I can tell you many things.

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Does the signal drift in frequency with time? Does it sound like a carrier or is there any modulation on the signal? When you say it comes and goes, do you see it most of the day on and off or see it for a few minutes and then not again for a couple of hours? What does the signal look like over a 10 to 15 minute time frame?

I am still not convinced at this point that you are looking at a satellite. Unless I see some evidence to the contrary I still think your signals is terrestrial. BTW you still have not told me your name.

73 de Larry

Does the signal drift in frequency with time?

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Yes!

Does it sound like a carrier or is there any modulation on the signal?

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It Sound like Random Noise.

BTW you still have not told me your name.

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Sorry anonymity is very important for me. I fear for my life when I write some Freq Stuff.
oh a new Phenomena:

Based on what you have described then I would say it is probably one of the Orbcomm low earth orbiting satellites.

her can you see it:
https://youtu.be/XA5OzTH_dDA?t=1m25s

Is there an Free Software for Orbcomm?

At this point there is no free Orbcomm decoding software. My good friend Bev M Ewen-Smith has a decoding package called Orbcomm plotter at https://www.coaa.co.uk/orbcommplotter.htm.
OrbcommPlotter can be freely downloaded and used for 21 days. After that time it must be registered. Registration can be done swiftly and securely on-line and costs only Euro €25 (plus VAT for EU residents) for personal use. It is a plugin called CombiPlotter provides you with a low-overhead means of displaying the satellite position received by OrbcommPlotter on another chart view. It will plot simultaneous data from ShipPlotter, PlanePlotter, OrbcommPlotter and SondeMonitor on a single chart.

I have used many of Bev's software packages including PlanePlotter and they are all top notch. Good luck in your monitoring.

73 de Larry, N5FPW

I use the Trail Version. now but sadly only one Channel like the other sshhtttt.... Application.
How about that: index

Patrick (F6CTE) Multipsk is a very fine package and I have a licensed version. Yes, in the newest package that was just released (I have not tried it yet) there is an Orbcomm decoder. To use it fulltime you must have a license otherwise you get 5 minutes of decoding only. This package will NOT decode any messages as they are encrypted. It will only decode the housekeeping downlinks and give the ORBCOMM satellites transmit identification, frequencies, position and orbital elements pieces of information, not encrypted. These frames are decoded and interpreted by Multipsk. Messages frames are decoded by Multipsk but not deciphered. As a general use all around decoder Multipsk is the best going for the money. Guess I need to try out the the Orbcomm decoder in this package as well.

I dont want decode it in the future. Now its a little interesting.
I will try to decode some Weather Pictures. It work nice. Sure I would need some helical Antenna for better reception.
In some minutes an NOAA Sat pass me.
NOAA Sat Reception is good for Prepper *gg*.

Airboss said:

There are a lot of old satellites in this range that still are sending their downlink signal here even though they are no longer operational. Many years ago I wrote a popular series of books for the radio monitor satellite enthusiasts called "Communications Satellites." I still have a large database of satellite frequencies, including the 136-137 MHz range. Pass along the frequency and I will be more than happy to see if I can find a match and we can go from there.

So would you pass along the frequency. It was not in your original message. I also need to know your location (you might also want to throw in your name), and if you receive the signal constantly or intermittently and how often.

73 de Larry, N5FPW

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I monitored the entire 136-137 MHz for a solid week last month. When I say monitored for a single week I mean every second. The waterfall display displays 20 seconds at a time. I capture the screen every 20 seconds so nothing is lost. Those are combined to make a movie that can quickly be viewed. These are the only satellites I saw active at this time:
136.653 OPS6582 (Transit 5B-5) which is thought to be perhaps the oldest still transmitting satellite.
136.770 NOAA-19 BCN/DSB
136.770 wandering intermittent carrier from NOAA 9 which is not being used.
Satellites were verified by specification and orbital tracking.
I am afraid your database is mostly dead frequencies.
Keep in mind that in the US this band has been allocated to aeronautical use. I see ACARS on 136.85 MHz and VDL2 (Google) it on its only frequency of 136.975.
For 137-138 MHz, seen were:
137.100 NOAA-19 APT
137.225 Orbcomm
137.250 Orbcomm
137.2875 Orbcomm
137.350 NOAA-15 & NOAA-18 BCN/DSB
137.440 Orbcomm
137.460 Orbcomm
137.560 Orbcomm
137.620 NOAA-15 APT
137.6625 Orbcomm
137.6875 Orbcomm
137.7125 Orbcomm
137.7375 Orbcomm
137.900 Meteor- M N2 LRPT
137.9125 NOAA-18 APT
(There might be an unknown satellite at 137.852)

At 149-151 MHz:
149.940 COSMOS navigation/store-and-forward (also beacon on 399.840)
149.970 COSMOS navigation/store-and-forward (also beacon on 399.920)
(149.910/399.780 and 150.030/400.080 were no longer seen; nor were the old USN TRANSIT satellites)
150.012 GEOSAT beacon (despite the way the name sounds, this is NOT a geostationary satellite)
150.012 DMSP 5D-2 F15 (USA 147) beacon (also on 400.320)
150.012 other unidentified satellite beacons
At 399-400 MHz (I have yet to review my 401-402 MHz and other bands including finding some frequencies not reported--these later):
399.840 COSMOS beacon (see 149.940)
399.920 COSMOS beacon (see 149.970)
400.032 Cassiope beacon (also beacon on 1066.752 seen)
400.032 GEOSAT beacon (also on 150.012)
400.032 DMSP 5D-2 F15 (USA 147) beacon (also on 150.012)
400.100 Orbcomm beacons
400.170 Perseus M1
400.220 Perseus M2

majoco said:

Satellite Radio Transmission Frequencies

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Although a nice historical reference, a large amount there is outdated as even that list notes some of the transmissions have not been seen since 10 years ago. Like a lot of people's refrigerator, lot of things on INTERNET, stuff stays for well passed its spoil date if not forever. Much (most?) in the list are long dead and it does not even include the recent NOAA satellites so is not maintained in regard to what is actual current activity. the list I just put in this thread is a much more accurate picture of current activity.