Astro25's won't unmute with proper PL, HT1250 works fine...

[YouHF]

I've been beating my head against the wall on this one. About a week ago, it seems my local PD may have made some changes to their conventional system, possibly a new repeater - not sure, but they were moved to another regional channel for a few days. Since then, my previously-working XTS5000 and XTL5000 will not unmute. I thought they perhaps changed PL/DPL, but it appears that they did not. My HT1250 continues to work. I programmed up a new (to me) XTS2500 and have the same issue.

So to summarize, I have 3 separate Astro25 units that all refuse to unmute, while the HT1250 works fine. I also verified via my Pro-106 scanner that the frequency indeed has the same 85.4 PL it's always had.
Details:
Band: UHF-T (47x.xxx)
Type: Analog, Conventional
PL: 85.4
Radio 1: XTL5000 S-split, previously working on this channel, now will not unmute, but receives when pushing monitor
Radio 2: XTS5000 Q-Split (so slightly out of band), previously working on this channel, now will not unmute, but receives when pushing monitor
Radio 3: XTS2500 S-split, newly programmed, will not unmute, but receives when pushing monitor
Radio 4: HT1250 S-split, previously working on this channel

Do you think it could be a tolerance issue with the PL? The department uses XTS5000 and XTL5000, so I'd be shocked if it's a wider compatibility issue. I know there are documented issues with signal overload, but that is not the case here. The 3 Astro's are different firmware ranging from <10 to R17 for the 2500. None have been aligned recently, but it would be hard to believe all 3 would have an alignment problem at the same time. Any ideas?

 

[com501]

Programming changes in the radios?
What is the measured PL deviation?

Most common issue is usually other signalling being enabled and the 'and' signalling selector being enabled instead of 'or' signalling. (example: MDC decode AND pl decode instead of OR, or QCII plus PL).

 

[Alpha]

My guess would be did the system just go to narrow band, or has it been recently re-aligned? If you have a narrow band channel programmed in your units as wideband, the PL level may not be enough to be detected at its new lower level. Com501's observations are on the money otherwise, actually measuring the transmitted PL level will tell a lot.

 

[kodiak]

Did they switch to a simulcast system? I've had the exact same issue with a simulcast system and heavy overlap areas. Never got over the problem, had to re-program the mobiles to CSQ receive. I have a feeling it was a simulcast alignment problem that never was resolved by the shop.

 

[YouHF]

My guess would be did the system just go to narrow band, or has it been recently re-aligned? If you have a narrow band channel programmed in your units as wideband, the PL level may not be enough to be detected at its new lower level. Com501's observations are on the money otherwise, actually measuring the transmitted PL level will tell a lot.

Did they switch to a simulcast system? I've had the exact same issue with a simulcast system and heavy overlap areas. Never got over the problem, had to re-program the mobiles to CSQ receive. I have a feeling it was a simulcast alignment problem that never was resolved by the shop.

Both of these are possibilities. I'm going to try to find out what happened. I know at least part of the regional system narrowbanded a year or so ago, and specifically changed from PL to DPL to ensure that they reprogrammed all the radios. Even if this was the case though, wouldn't this only be a problem when transmitting, not receiving? I'm receive-only. I don't even think it gives you the option to choose narrow/wide for a receive-only personality.


As for a possible switch to simulcast, if this was causing me problems on 3 separate Astro25 radios, wouldn't the PD's XTS5000 and XTL5000 radios have the same problem (which I know is not the case)? Are there any settings to change in the programming if it is changed to simulcast? I didn't think so at least for analog.


Otherwise I guess I'll pull out my service monitor that I don't really know how to use ;-) and see what the PL deviation looks like...

 

[Alpha]

For a receive-only personality you have to momentarily turn on TX, then you can adjust bandwidth, then turn TX off again. I'm not 100% sure, but I believe the radio looks for a certain level of PL that is dependent on whether the channel is wideband or not. I could be wrong, but it's something that's relatively easy for you to try out and certainly will not cause any harm, in any case. Some radios are more sensitive to PL levels than others.

I do not know of any simulcast-specific settings for subscriber radios, similar to CQPSK in digital modes.

 

[YouHF]

For a receive-only personality you have to momentarily turn on TX, then you can adjust bandwidth, then turn TX off again. I'm not 100% sure, but I believe the radio looks for a certain level of PL that is dependent on whether the channel is wideband or not. I could be wrong, but it's something that's relatively easy for you to try out and certainly will not cause any harm, in any case. Some radios are more sensitive to PL levels than others.

Go figure. This fixed it on my XTS2500. I'll try the others tomorrow. Thanks for the suggestion as I did not previously think the Tx deviation setting made any difference for Rx.

Earlier tonight I reproduced the failure to unmute on two other XTS5000's (one I know is programmed wide) but did not reproduce on someone's XTS2500 with newer firmware. I'll ask him if he has it programmed narrow or wide.

 

[motoham88]

I thought T-band was exempt from Narrowbanding?

 

[motorola_otaku]

Astro25 subscribers are extremely critical of analog audio levels on receive. You don't have to go much above 5 kHz deviation before the receiver won't unmute. I've beaten my head against the wall with ham repeater owners who keep insisting "there's nothing wrong with the repeater, it's just your radios" when their total output deviation peaks above 5 kHz.

On a narrowband system PL deviation should be in the 300-350 Hz range and no more than 500 Hz on a wideband system. Total output deviation should not exceed 2.5 kHz for narrowband and 5 kHz for wideband, with the optimal levels being 2.2-2.3 narrowband and 4.1-4.5 for wideband. Kind of hard to tell without having the repeater output plugged into a service monitor but I would lean towards that if you're sure your programming is correct.

 

[YouHF]

Go figure. This fixed it on my XTS2500. I'll try the others tomorrow. Thanks for the suggestion as I did not previously think the Tx deviation setting made any difference for Rx.

Earlier tonight I reproduced the failure to unmute on two other XTS5000's (one I know is programmed wide) but did not reproduce on someone's XTS2500 with newer firmware. I'll ask him if he has it programmed narrow or wide.

Confirmed the fix on a second radio. Thank you all for solving this!

 

[thaforce]

We actually had a similar issue to this with our XTL radios not unmuting intermittently. The easiest solution for us was to bump up the PL audio a bit on our repeater system. We set it to about 350Hz(Narrowband )for the problem to completely go away.

 

[Pezking]

We actually had a similar issue to this with our XTL radios not unmuting intermittently. The easiest solution for us was to bump up the PL audio a bit on our repeater system. We set it to about 350Hz(Narrowband )for the problem to completely go away.

That seems like the ham thing to do. Dick with the repeater when the problem clearly lies in the subscriber equipment.

This is no different than not running CTCSS or DPL and running carrier squelch because some hammy junk doesn't support it.

 

[thaforce]

That seems like the ham thing to do. Dick with the repeater when the problem clearly lies in the subscriber equipment.

This is no different than not running CTCSS or DPL and running carrier squelch because some hammy junk doesn't support it.

It seems quite different to me. If the problem were a handful of radios we would have taken a different approach. It is a bit different when trying to co-ordinate the realignment of 2 large fleets of vehicles. The solution was quick and able to be done remotely. I wasn't suggesting this as life advice, I was just sharing our K.I.S.S. solution to what seemed like a huge problem at the time. As they cycle through for maintenance the issues will eventually get resolved. In the meantime everything is working fine with no ill affects from a slightly boosted CTCSS level.

 

[Astro Spectra]

Several Astro and Astro25 FW versions have PL decode issues as noted in the release notes.