100% signal, No frequencies? (Unitrunker)

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MilAirNJ

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BM82557

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The bandwidth setting in SDR# is 10, way to narrow, change to 12500. What is 852.5750? It isn't listed for any of the sites in your link.
 
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MilAirNJ

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Thanks for the reply, I tried switching the setting to 12500, and still nothing. That frequency is from Site 18. The frequencies are always off by a few digits. Not sure how to fix that. The correct frequency should be 852.7000
 

nd5y

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It's an EDACS system. They don't send frequency or band plan data on the control channel like P25 and Motrola systems. The only thing sent is the LCN. There is no way Unitrunker can tell what the frequencies are.You have to set the proper frequency for each LCN.
 

Spitfire8520

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An EDACS system doesn't have a trunking table or predefined voice channels like some other trunking systems you might have messed with before. Due to this, Unitrunker cannot figure out the frequencies itself and is why scanners require knowing every frequency and their specific LCN placement. Much of the information in the database was manually figured out at some point through various means.

The frequencies are always off by a few digits. Not sure how to fix that. The correct frequency should be 852.7000
You need mess with the ppm setting by clicking on the gear icon on the top left. Changing the ppm positively should move the signals to where they need to be. Each individual SDR generally has a different ppm setting and doesn't have a universal correct setting.
 

mk262

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fwiw I would strongly recommend using the r820t natively in UT instead of via sdr#
 

SCPD

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No one pointed this out ...

You've set an Offset to "correct" the tuning error inherent to your RTL stick.

Don't do that. The reason you don't want to use the Offset is the error increases with frequency.

What you want is to set the correction or "warp" value. The value is in parts per million. Click on the gear tool in SDR# to see this setting.

An error of 1 parts per million at 100 megahertz is only 100 hertz. At 851 Mhz, that error is 851 hertz.

The clock inside your RTL stick is likely only good to 50 or 100 parts per million.

You can use SDR# to calibrate your RTL stick. Let SDR# run for 10 minutes or so to allow the RTL stick to warm-up.

Tune SDR# to a known control channel. The real signal will appear in the waterfall somewhere to the right of the red line.

Manually increase the warp value - until the red line is centered over the spike.
 
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MilAirNJ

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Thanks for the great feedback, and taking the time to correct some of my problems! Its running beautiful now!
 

hamjamman

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Hello! Sorry to piggyback, but my issue is directly related and may help OP.

Same deal, working with EDACS - no frequencies listed. I have no problem filling in the channels manually but I can't seem to get Unitrunker to remember the control channel! If I move away and come back after letting it know where I was tuned in at, it thinks it is decoding a whole new system and doesn't have any of the channel frequencies saved.
How do I do this properly, so Unitrunker knows when I've arrived back at a control channel I've filled in data for already?
 

SCPD

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I can't seem to get Unitrunker to remember the control channel! If I move away and come back after letting it know where I was tuned in at, it thinks it is decoding a whole new system and doesn't have any of the channel frequencies saved.
How do I do this properly, so Unitrunker knows when I've arrived back at a control channel I've filled in data for already?
Good question. Use the Pick Site feature to explicitly tell the program while site you're monitoring. If you do see a site window appear with the prompt "Frequency needed!" - type in the control channel frequency. That is usually enough of a clue for the program to find and switch to the previously logged site information.
 

hamjamman

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Thank you so much for the quick reply! I'll give that a shot but right now I'm running into an issue preventing me from even getting that far.
Unitrunker seems to be "losing" the control signal, going from about 95% green bars to completely disappearing. Issue is not thermal drift, dongle has been in use for over an hour and furthermore I can stop and restart the signal and it picks it up instantly, no problem, with nearly full bars again. Recently upgraded to 1.0.32.7.

PS - Thank you SO much for all your hard work and community outreach, you really do a great job. Are you on ##rtlsdr IRC?
 

SCPD

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Unitrunker seems to be "losing" the control signal, going from about 95% green bars to completely disappearing. Issue is not thermal drift, dongle has been in use for over an hour and furthermore I can stop and restart the signal and it picks it up instantly, no problem, with nearly full bars again. Recently upgraded to 1.0.32.7.
Please give us more information on your receiver configuration. We may be able to help.

Are you on ##rtlsdr IRC?
IRC? Not so much.
 
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