P25 receive muted

[wuzafuzz]

Has anyone else noticed EFJ 5317's failing to activate receive audio for P25?  We have started noticing our radios mute the receive audio on digital channels unless we place the radio in monitor mode. Unfortunately the default is "Squelch Select."  Users unfamiliar with this issue will hear nothing.

We have checked the codeplugs and confirmed they are set to receive the proper NAC and CTCSS.  Mixed mode is enabled.  Selecting the Digital Squelch button in the software does work, but then it unmutes for all NAC's.

I've had no trouble at all with my personal Motorola radios.  They unsquelch just fine when receiving from the EFJ radios, the repeaters, or any other source.  Other members with personal owned radios (Icom, Motorola, Kenwood) work fine as well.  It's just the EFJ's that won't speak up.

[kd8gua]

Since you can read the code plug, you can change the code plug...

Try changing the receive NAC codes for your channels in question to F7E. F7E is known across all P25 radios as the digital form of carrier squelch. The radio should unmute on receiving any NAC. Just remember to not change the transmit NAC, only the receive.

If that still doesn't remedy the problem, the radio may need alignment. If the tuning frequencies are too far from the required RX frequency or just not with the right settings, the radio will not even acknowledge a signal (ie. you won't even have the RX indicator light up).

Also, if your repeaters are still mixed mode, test the EFJ radio's transmit in P25 on that repeater, and have one of the known working radios listen first on analog and then on digital. I have seen an Astro Spectra that was factory bandsplit from 146-174 that was adjusted to TX down to 136. P25 RX stops working around 144 because the tuning frequencies and information remained the same and so there was no tuning information for 136-144. I was unable to validate whether P25 TX worked in these frequencies, but analog TX and RX both worked just fine.