TRX 1&2 on a 700 MHz Phase 2 Simulcast System

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ScanNEIN

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I am attempting to monitor a new Atlas 700 MHz simulcast system with my TRX's. I am getting horrible reception. Have tried different antennas, it is on an outside antenna now and still not getting much traffic. Not even going digital, it is missing a huge amount of traffic. I am 8 miles from the closest tower. I am also monitoring the IN SAFE-T System, it comes through clear. Are the TRX's not good on a simulcast system? Not sure what else to try other than a new radio.
System monitored:
 

Whiskey3JMC

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So many different threads created on the forums discussing simulcast distortion, it's perhaps among the top 10 maybe top 5 topics discussed here? Yes, it's known to greatly affect the entire Whistler line. You'd be much better off with the Uniden SDS100 or SDS200 to bring simulcast systems in. I briefly owned a TRX-1 and ran it side by side with my SDS100. Night and day difference, that I can tell you. And I have about 10 simulcast systems in my region I monitor from time to time
 

Ubbe

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it is on an outside antenna now and still not getting much traffic.
It's important to adjust the signal level to only receive one tower. You can use the scanners built in 20dB attenuator and you probably need an adjustable 0-20dB on top of that to adjust to a level where the other offending towers are just barely out of range. If the two strongest towers have equal strength then you must change their relationship by using a directional antenna, a $25 investment from Amazon.

/Ubbe
 

W4KRR

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I sold my TRX1 because it wouldn’t work on my local county simulcast system. Literally almost no clear audio.
 

tvengr

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Baltimore County, MD
I don't see any programming errors with the ATLAS system. I added Grant County EMA Dispatch and Grant County EMS Dispatch. I agree that you are most likely experiencing simulcast distortion. Here is the updated file:
 

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Skypilot007

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It's important to adjust the signal level to only receive one tower. You can use the scanners built in 20dB attenuator and you probably need an adjustable 0-20dB on top of that to adjust to a level where the other offending towers are just barely out of range. If the two strongest towers have equal strength then you must change their relationship by using a directional antenna, a $25 investment from Amazon.

/Ubbe

This is all great information. I'm lucky enough that my home is in an excellent location for both P25 Phase II systems in my area and I can get away with using a TRX-2 or a one of the legacy Uniden scanners with excellent great results without using attenuators or yagi antennas. But when I go mobile with the TRX-2 or a legacy Uniden scanner they are nearly useless. Trying to make antennation adjustments and other things are not practical when driving. I've tried many things to make the TRX-2 work when mobile to no avail. It simply is not a viable solution for P25 phase II LSM systems when mobile.
 
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