Linear Simulcast

[Dhubjr]

Hello all, Sorry if this is a repeat question but,,,,,

I was looking around the RR database at several local counties and could not find a list or reference as to whether an agency is using LSM. Did I miss something somewhere? I have an SDS100 because I know my local county sheriff uses LSM (Kenosha WI) but a co-worker who lives north of me on the border of Milwaukee and Waukesha counties want to know if he can get by with a BCD436 up there. Thanks in advance.

-Dhubjr

 

[GTR8000]

LSM (mostly) only applies to P25 trunked systems. There are some P25 conventional simulcasts that use LSM, but they are fairly rare. Some P25 systems might list the modulation in the site details, but it's not a requirement and thus is hit or miss.

Rule of thumb: If a P25 system has a simulcast cell, it's using some form of LSM or CQPSK modulation. P25 Phase II systems use H-DQPSK for the TDMA talkgroups/traffic channels even if the site is standalone (C4FM) and not simulcast.

Basically if you're listening to P25 trunking and there is a simulcast cell and/or TDMA at play, most scanners except for the SDS series is going to struggle with it.

 

[Dhubjr]

Thanks for the info. I found out the hard way that my local sheriffs office was using conventional LSM. I started out with the BCD325P2, had problems, researched it, found out it was LSM, was given bad info that the 436HP could handle LSM, and that was my second return to Amazon. Lol... obviously I eventually ended up with the SDS 100 that I love. It's not perfect, playing with the filters helped (use Normal for anyone in Kenosha county that's interested) but I just want to make sure I am giving my coworker good information before he spends that kind of money. Time to browse the database and check for simulcast cells. Thanks again!

 

[DVINTHEHOUSEMAN]

Conventional LSM is becoming less and less rare, at least in Wisconsin. So far, Clark, Eau Claire, Green, Kenosha, and soon Rusk counties, as well as the city of Chippewa Falls, are operating CQPSK simulcast. It would not surprise me to see some of the analog simulcasts around the state go P25 as well.