BCDx36HP: Favorite List Simulcast Priority Scanning Tip

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jonwienke

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Some areas have trunked systems where some talkgroups are simulcast on conventional analog FM frequencies. The analog simulcast may be on low band for coverage where an 800MHz freq may have difficulty reaching (rough terrain), or it may be needed for existing Fire Tone Out pagers. In many cases, the trunked system audio quality is significantly better than the simulcast, but scanning both is desirable if the trunked system fails. The obvious thing to do is to give the trunked system priority when scanning, but still scan the analog channel. There's a simple way to do this!

Let's say that Podunk County has a P25 trunked system that handles all county and public safety radio traffic, but it also has some conventional analog frequencies that simulcast FD and EMS dispatch. The audio quality of the P25 traffic is better than the simulcast analog, so you want to monitor the P25 system unless it is offline for some reason (in which case you want to hear the analog FM simulcast instead of nothing). Here's how to do it.

First of all, rotate the scroll knob clockwise during normal scanning. This will force the scanner to scan the main DB or favorite lists top to bottom as they are shown in Sentinel.

Let's say we have 2 systems for Podunk County: Podunk P25 and Podunk Conventional. Podunk Conventional has the dispatch simulcast frequencies that duplicate some of the P25 talkgroups. If you sort the systems in the favorite list so that Podunk P25 comes before Podunk Conventional, when someone keys the mic on a FD or EMS dispatch channel, the scanner will encounter the P25 system transmission first, and will pause scanning and open squelch. When traffic ends, the scanner will still scan the analog channels after it is done with the P25 system, but will generally not see any traffic on the analog simulcast channels unless a user times a follow-up transmission just right. Depending on the system names, you may need to manually move one of the systems up or down in the favorite list.

You can use a similar trick on multisite systems where one site has significantly better reception than the others. Move it to the top of the system's site list, and that site will be scanned first. Any transmissions simulcast on multiple sites will be received from the site you moved to the top of the list. But if there is traffic on other sites not carried by the preferred site, you will still hear it.

The main caveat here is that this trick only works if the scanner is scanning "forwards"--top of the list to the bottom--which happens when you turn the scroll knob clockwise during normal scanning. If you turn the scroll knob the opposite direction, scanner will scan through lists in the opposite direction, and the simulcast priority effect will be reversed.
 
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