Software for decoding Morse Code/CWID tones

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natedawg1604

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So, I'm looking for an easy way to extract/decode call signs from various CWID tones on LTR systems. Does anyone have recommendations for good software to accomplish this?

Here is a link to a CWID tone from an LTR system I've been trying to decode:

https://www.dropbox.com/s/zaeov6kwgc30044/scanner%20decode.wav

I've been trying to decode the call sign from this audio file with CwGet, but it hasn't worked so far. I'm wondering if the LTR system which generated this CWID tone is using some kind of compression or something, not sure.
 
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natedawg1604

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Data, not code, almost like aprs sounds, without the tnc decoder
Okay, good to know. It's definitely an LTR LCN frequency, LTR Logger captures LTR status data from this data burst. I guess I was thinking it might also contain "compressed" morse code, but it obviously doesn't.
 

DSheirer

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So, I'm looking for an easy way to extract/decode call signs from various CWID tones on LTR systems. Does anyone have recommendations for good software to accomplish this?

Here is a link to a CWID tone from an LTR system I've been trying to decode:

https://www.dropbox.com/s/zaeov6kwgc30044/scanner%20decode.wav

I've been trying to decode the call sign from this audio file with CwGet, but it hasn't worked so far. I'm wondering if the LTR system which generated this CWID tone is using some kind of compression or something, not sure.
You can visually decode a morse CWID by recording the audio to a wave file and then open it in Audacity. Use the zoom in/out function to adjust the display so that you can see just the CWID burst. The longer tone transmissions are the dashes and the shorter ones are the dots. There's usually a slight pause in between each letter that you can also see on the display. Highlight a section of samples and hit Ctrl-B and you can type a label, so that you can label each character as you decode it. Google has tons of morse code charts.

You can visually decode the LTR signalling in Audacity too, but that's a painful exercise.

Denny
 

DSheirer

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So, I'm looking for an easy way to extract/decode call signs from various CWID tones on LTR systems. Does anyone have recommendations for good software to accomplish this?

Here is a link to a CWID tone from an LTR system I've been trying to decode:

https://www.dropbox.com/s/zaeov6kwgc30044/scanner%20decode.wav

I've been trying to decode the call sign from this audio file with CwGet, but it hasn't worked so far. I'm wondering if the LTR system which generated this CWID tone is using some kind of compression or something, not sure.
It's a 1200-baud AFSK modem. 0xDC14 is the possible 16-bit sync pattern following the 16 x bit revs.

It's not Fleetsync 1 (sync=7650) and it's not Fleetsync 2 (sync=23EB) and it's not MPT1327 (sync=A4D7 or 3B28). It's not MDC-1200 (no NRZ-I on the bit revs). It's not APRS (no HDLC flags).

It may be some form of SCADA. If you can correlate the licensee to a local two-way radio vendor, check the vendor's website and see if they offer SCADA/data services over their network.

How often are you hearing these bursts? Is there any other voice/data/signalling on that channel? If you are decoding LTR, is it the same talkgroup for each data burst?

Denny
 
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natedawg1604

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....
How often are you hearing these bursts? Is there any other voice/data/signalling on that channel? If you are decoding LTR, is it the same talkgroup for each data burst?

Denny
I'm hearing these bursts every 5 minutes on 152.1500, TGID 0-15-037. I also hear a 10-sec LTR burst. TGID 0-15-037 reports Free LCN's 9 and 15, it's part of a 3-LCN LTR system somewhere in the Denver-Metro Area as follows:

152.5400, LCN 9
152.8100, LCN 13
152.1500, LCN 15

I've only been tracking the system for a week, but so far I've not heard any voice grants on LCN 15. I have heard voice traffic on LCN's 9 and 13. LCN 9 (152.4000) also registers a similar data burst every 5 minutes on TGID 09-030. LCN 13 (152.8100) has no data bursts, only the 10-sec. LTR burst.

I've not yet been able to decipher a system owner or even a site location from ULS, it appears to have been constructed from blocks of paging frequencies.
 

DSheirer

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Intermountain Rural Electric is licensed WQMW961 for 152.15.

On page 2 of their 2012 annual report, they reference investments in a new digital radio system and SCADA monitoring for 25 of their 48 electric substations.

Intermountain Rural Electric Association

The report also mentions AVL. We have a ton of companies and school bus fleets using Fleetsync AVL GPS bursts over LTR here in central NY.

Here's another compelling link talking about their Survalent SCADA system that uses a 150 MHz land mobile radio system along with fiber and microwave for both substation monitoring and AVL (google: NERC Intermountain Rural Electric Association NCR11226):
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=5&cad=rja&ved=0CEkQFjAE&url=http://www.nerc.com/files/TOP%20Certification%20of%20Intermountain%20Rural%20Electric%20Association.pdf&ei=US_4UrCkMcjs0wGpvoEI&usg=AFQjCNGLqa2TeY9Z5hvbDIwOQNIGgg-ncw&sig2=4n1eXk20MJDydQAJLr5RVQ&bvm=bv.60983673,d.dmQ

Is the voice activity on the other channels consistent with electric company type calls? Can you get a recording of the data bursts on the other LCN and post it?
 
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