SDS100 trouble tracking Utah Motorola system 420F

gldavis

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Utah-Motorola system 420F, SLCo PW.
Info was downloaded from RR database.
when using 858.7125 as control channel, radio tracks conversations properly. except for freq 856.7125. it is distorted. Sounds like it is off freq a bit.
when using 857.7125 as control channel, unit will not track at all.
TRX-1 & 2, GRE-500, and a PRO-197, all work fine on this system.

Any ideas?
 

tvengr

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857.7125 is not listed as a control channel. You must use 858.7125. There would have to be a problem with 856.7125 on the radio system or you have interference on that frequency. Export a hpe file of your favorites list and attach it. I will check it for problems. You will have to right click on the hpe file and send it to a compressed (zipped) folder to be able to attach it.
 

gldavis

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Using Unitrunker to decode the data channel (TRX-2), shows 858.7125 and 857.7125, alternating every 24 hours, as control channel. I've made sure that the freqs shown by Unitrunker are in the system freq list in the radio, and ........Wait a minute.......Is the SDS100 told what channels are used for control, and only use that channel for info? If so, why program in the voice channels? I am use to my radio's, "searching" the programmed freqs, and locking onto the control signal. Or am I still missing something?
disclosure- Sentinel is not my friend. After downloading/uploading, I've been adjusting the favorites list, via the front panel.
856.7125 - I have several other radios programmed with this system, and they all track fine.
 

jonwienke

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Is the SDS100 told what channels are used for control, and only use that channel for info? If so, why program in the voice channels?
The scanner will search all trunked site frequencies in the order listed, until it finds a control channel. You want to program all site frequencies to cover the possibility that they might change the control channel. If you program the control channel(s) first, it doesn't slow down scanning, because the frequencies at the bottom of the list will never get scanned if the scanner finds a control channel at the top of the list.

disclosure- Sentinel is not my friend. After downloading/uploading, I've been adjusting the favorites list, via the front panel.
Learn it anyway. FPP programming is a lot easier to screw up. And if you make a change in Sentinel, you don't have to redo it every time you update the radio. There are plenty of YouTube videos on the subject, spend a minute or two searching and you'll find plenty of info.
 

gldavis

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I got tired of being able to listen to the SL Co PW system, every other day,,,,,so I downloaded from the radio, used Sentinel to delete the system, and went to reload the system, fresh from the Radio Reference web site. I think I goofed. I can't figure out how to download/update just the one system. I looked thru the user manual, and went thru 'marksscanners" web site. (Great info, by the way. It has helped in the past.) No luck.
Fortunately, the radio still has the info.
I exported the hpe file, but RR won't let me attach.
 

gldavis

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Okay. I think that has it. Thank-you for your help and patience. I switched the usage of my radios, and am using the GRE500 for this system (works great), and the SD100 is parked on the local PD channel.
Again, thank-you for your help and patience.
 

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gldavis

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The SDS100 will not track this system, when the control channel is 857.7125.
Radio will track, when control channel is on 858.7125. but, any traffic on 856.7125 is distorted. Sounds like it is off freq by a bit.
The system changes control channel every 24 hours.
I can/have used TRX-1, TRX-2, PRO-197, and GRE500 for this system. They all work fine.
I use Unitrunker to verify freqs and traffic.
Sentinel claims that SDS has latest firmware (as of yesterday morning).
Any help will be greatly appreciated. I was looking at Youtube videos for this radio, last night. I'm accustom to using manuals to learn how something works. Using Youtube to operate, instead of a manual, is new to me. This radio has some amazing capabilities.
 

jonwienke

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Voice traffic isn't carried by the control channel, so what are you basing your distortion comment on?

Have you tried IFX in the problem frequency? Enabled a filter for the site?
 

gldavis

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The system changes the control freq at midnight, every night. Example,,,, yesterdays control freq was 858.7125. Today's control freq is 857.7125. Tomorrows control freq will be 858.7125 (every other day). The unused control freq is used for voice traffic, for that day. The audio distortion (off freq just enough to distort the audio) is only on the one freq, 856.7125. All other freqs are good/okay. But this is only when 858.7125 is the control freq. The radio will not track the system when 857.7125 is the control freq. The system tracks and sounds fine on any of the other radios I have.
Filters are set to global. I was thinking about the IFX, but didn't want to fool with it, until I'm more familiar with the cause and effect of making such a change.
 

jonwienke

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Filters are set to global.
That's meaningless unless you mention what the global setting is.

I was thinking about the IFX, but didn't want to fool with it, until I'm more familiar with the cause and effect of making such a change.
It changes the intermediate frequency used by the radio when tuned to a specific frequency. It can eliminate a birdie and some forms of interference.
 

522

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I've loaded the file you provided to my SDS100 and have been scanning only that for an hour now, and not one thing has come on as of yet.
 

522

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Ok, and to be fair... I loaded the Salt Lake County Public Works Directly from Sentinel and let that run for an hour.

I only got Two hits, but I will agree with gldavis .... it definitely sounds off frequency.

I'll add some video here shortly.
 

gldavis

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Tomorrow the Garbage, landfill, and road crews, will be operating. Lots (lots) of day traffic from them. Thanks for helping out.
 
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