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Newb Unitrunker help please

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#4
You can assign a priority or rank to each group or user. On the main options tab, you can set the priority threshold. Calls ranked as 1 are more important than calls ranked as 2. The default ranking is 50.
 
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#5
OK making good progress.
I now have all of the TG's labeled and prioritized. I can receive a huge number with just a single dongle.

What I do notice is a warbling/whistling sound during the repeater tail just after anyone stops talking or if the mic is keyed and nobody talks on all call groups. I have made a recording if that would be useful.

Does this sound like a problem with the 800Mhz system here, Unitrunker or the Nooelec dongle?

I have tried different gain and squelch settings but was only able to make it sound worse.

Thanks for the help.
 
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#6
An end code (a stream of repeating 10101100 bits sent at 300 bps) is transmitted at the end of each analog voice call. That would be the warbling you're hearing. Don't know if UT has an end code detect feature that would mute that.
 
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#7
This is not an end code, it can be heard all the time as long as a transmission is taking place.
It's sounds like part of the carrier which is more obvious once the PTT has been released and before the tail drops out. Listening to audio is fine is this warble is only faint in the background.
Happens on two different systems that I listen to.
I guess it must either be the dongle or a setting in UT that I need to find.
 

natedawg1604

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Sounds like some type of outside interference feeding into the dongle, possibly electrical noise on the ground line, or another device generating spurious noise. Do you hear this noise on analog conventional signals (i.e. conventional repeater such as a local NOAA station, public safety VHF/UHF repeater etc)?

Also, how exactly is your dongle connected to the computer? RTL dongles tend to be sensitive (not in a good way) to spurious noise from a large variety of sources.
 
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#12
Window value hovers between 10 and 30. Any slight adjustment I make to the drift correction gets the windows value closer to zero but at the expense of some scratch on the signal.

The dongle is plugged directly into my laptop. I have tried running off battery power and turning off the external monitor.

Using SDR# to monitor an analog signal the sound is not present.
 

exkalibur

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#14
Yup, that's just mild simulcast distortion.

The (old) Public Safety system here was 800MHz with a bunch of simulcast sites. Even on a "real" Motorola radio, the exact sound in your recording was present.

"Live with it" is unfortunatly going to be your only option, aside from figuring something out with a beam as SW said.
 
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Thanks.
It's not a really big hassle and easy to live with.
I'm quite fortunate, using the supplied magmount antenna placed on the side of an old computer near a window, I am getting hits on all of the 16 frequencies in the San Diego City 800MHz system with all the control channels being seen as well.

What I have found from time to time is the primary control channel stop transmitting and I have to manually switch one of the alternative ones to the VCO park position.
 
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#16
I see in the bottom section of the site call event history panel many calls, joins etc. like one every second or so but in the top section active calls many seconds can go by before a channel is heard (frequency goes green).
I also see a number of calls appearing in the active call windows, sometimes 7 or 8 at a time without any one of them being locked onto.

I have been playing with priorities both for TG's (PD TG's are from 1 - 5, FD from 6 - 10 etc.) as well as certain users, eg. if the source is the dispatcher on any of the PD calls then I have made them a priority of 1.

So what does it mean as more and more entries pop up in the active window but don't get locked on to ie. periods of silence even though many active calls? Likewise what does it mean with so much activity in the history window without corresponding activity in the active call window?

Thanks.
 
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#17
So what does it mean as more and more entries pop up in the active window but don't get locked on to ie. periods of silence even though many active calls?
The "Svc" column will tell you the whether the call is voice, data, or encrypted. Data and encrypted calls are ignored. If you're using a single Realtek, the program is limited to a region less than +/- 2 Mhz around the control channel. Many of your site's voice channels are outside that range. $20 bucks can solve that problem.

Likewise what does it mean with so much activity in the history window without corresponding activity in the active call window?
Only calls appear in the top panel. Lots of other events take place on a control channel even when no one is talking.
 
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#18
OK that makes some sense.
The Svc column almost always just shows - even when there is voice communications. Sometimes there is an MS or a Dig.

Running out of USB ports on my laptop! May need to look at getting a hub and then an extra dongle. I assume there is no problem mixing my existing Nooelec with an RTLSDR just to try something different.
 
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#19
OK that makes some sense.
The Svc column almost always just shows - even when there is voice communications. Sometimes there is an MS or a Dig.
The "-" means the program did not see the initial call grant. It knows there is a call active but it does not know (a) the source radio ID or (b) the specific type of call (eg. Dig vs. Ana). The usual cause is less than 100% decode rate of the control channel.
 
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#20
VCO health reading shows 100. This even with no antenna connected although with weaker sigs, as expected.
RSSI on the control channel is about 70 with antenna connected with window value of around -5 .

Every time there is an MS call svc shows it immediately but none of the others even though I can hear them all.

Will all of this improve with a second dongle?
 
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