TRX-1 Slow Scan of DMR and P25 trunked, missed transmissions.

[Davey1]

With my TRX-1 I am attempting to scan one P25 trunked system [Ohio MARCS] and a dozen conventional DMR channels. I am near all of the sites, less than 2 miles. The scanner receives the trunked system well, but it skips too much of the DMR traffic. Sometimes it gets those transmissions, but many times it doesn't. I know this because I have another radio that is set to only receive the 12 DMR channels. Is this a known problem, or is there something I can do to speed up the scan speed so I don't miss these DMR conversations as often as I do? Any help would be appreciated.

I attempted to attach my zip file, but it was too large.

 

[RaleighGuy]

With my TRX-1 I am attempting to scan one P25 trunked system [Ohio MARCS] and a dozen conventional DMR channels.

How many sites/TGs are you attempting to scan on Ohio MARCS? The more you are scanning the less it monitors. Also are you using priority on any TGs? There is no scan speed adjustment for the TRX scanners, and I wouldn't say it is a problem if it is how the scanner was designed.

 

[Davey1]

I'm scanning only 1 site on Ohio MARCS. I should have mentioned in my original post that I'm not using any priority channels on DMR and also no priority talk groups. Also, I'm listening to about 250 talk groups. [In an earlier thread, about two years ago, I was told that the number of talk groups shouldn't make a difference].

One additional question: Does the radio scan every frequency that is in the list on every scan pass, or does it remember which one is the control on multiple passes?

 

[sallen07]

One additional question: Does the radio scan every frequency that is in the list on every scan pass, or does it remember which one is the control on multiple passes?

The Whistler scanners do not trunk-track DMR or NDXN. They scan every voice channel each pass, looking for voice traffic.

 

[RaleighGuy]

Does the radio scan every frequency that is in the list on every scan pass, or does it remember which one is the control on multiple passes?

It does scan every frequency in the P25 list looking for CC traffic, but that shouldn't slow you down if you only have CC and SCC frequencies on one site.

 

[RaleighGuy]

The Whistler scanners do not trunk-track DMR or NDXN. They scan every voice channel each pass, looking for voice traffic.

a dozen conventional DMR channels.

That shouldn't be a factor if it is only a dozen conventional frequencies as OP said in Post #1.

 

[sallen07]

That shouldn't be a factor if it is only a dozen conventional frequencies as OP said in Post #1.

Yup. My bad. But I'm surprised it doesn't "remember" the P25 CC.

 

[Davey1]

It does scan every frequency in the P25 list looking for CC traffic, but that shouldn't slow you down if you only have CC and SCC frequencies on one site.

That may be where I've created my difficulty. I discovered that I have ALL of the frequencies for the site in the list. I will eliminate those that are not control channels. That will take away six frequencies.

 

[Ubbe]

The scanner receives the trunked system well, but it skips too much of the DMR traffic.

If you skip or lockout that P25 system, does it scan the DMR channels as it should? If you have the squelch set too low it will slow down scanning to a snails speed. Include a free analog frequency in the same frequency band and open squelch fully and let the scan stop on it and then turn up the squelch until it closes.

If you connect an earphone to the TRX-1 and set the audio for it to IF you can listen to what the scanner receives while it scans and you would be able to hear how long it stops on a frequency and also how long time it stays on that P25 system if you have it included in scan.

Conventional DMR are not transmitting any control channel when there's no voice traffic. So it has to scan those DMR's just when they are talking and also not tied up on the P25 system.

/Ubbe