LTR scan speed on 396XT

[davef3138]

I've noticed on my 396XT that when scanning Motorola systems, if there's no control channel signal present the radio will fly past the site/systems quite quickly. With LTR systems however, it will "dwell" on each system for about a second whether there's a signal present or not. (yes, the system hold time is set to 0)

Just curious why the behavior is different? It would seem logical that the scanner could skip over the LCNs with no signal present, slowing down to decode when it heard something.

 

[ka3jjz]

My first thought would be did you change the delay time on the system to zeros as well? 73 Mike

 

[DaveIN]

It would need time to check the LTR home channels for data, so it checks each LCN for a data burst one time, then moves on to the next programmed system. As Mike pointed out the delay could be extended by the system delay setting.

 

[davef3138]

System delay is set to 0 seconds, site hold time is also 0 seconds.

>It would need time to check the LTR home channels for data, so it checks each LCN for a data burst one >time, then moves on to the next programmed system. As Mike pointed out the delay could be extended by >the system delay setting.

I don't think it's waiting for a data burst...the data bursts occur every 10 seconds, but the "dwell" time is a consistent second or so. If I create a "bogus" LTR system with 8 LCNs, it dwells on it for the same amount of time as a fake (or real) LTR system with only 2 LCNs set up.

Maybe it checks the LCNs for a carrier multiple times within that ~ 1 second time, instead of checking them just once and moving on to the next system (which would take a fraction of a second)?

 

[davef3138]

For what it's worth, my old 246T also behaves the same way.

 

[kc0net]

Ltr

I found that my radio was doing the same thing, then i realized that the squelch was open.
Try adjusting the squelch, but often on digital signals you need keep it open.
Frank

 

[davef3138]

I've got the squelch on the 396XT set to "2", which keeps it closed on VHF & UHF conventional, non-PL/DPL channels.

I'll try cranking the squelch to the max (15) to see if that changes the behavior at all.

 

[davef3138]

Tight squelch setting makes no difference. I'm assuming it's the way the radios are engineered to decode LTR systems...