Multi-Site Trunked System Programming for Whistler/GRE Object-Oriented Scanners

From The RadioReference Wiki

Applicable Scanners

  • Whistler: TRX-1, TRX-2, WS1090, WS1098, WS1080, WS1088
  • Radio Shack: Pro-668, Pro-18
  • GRE: PSR-800

Issues with monitoring multi-site trunked systems

Earlier Whistler models such as the WS1040/WS1065 (and their Radio Shack/GRE variants) offer multiple scan modes for multi-site trunked systems:

  • Stationary - Scans all control channels being received (and thus all sites).
  • Roam - Scans all control channels being received, selects the best, stays there, and only re-scans if reception is lost.
  • Off - Stops at the first control channel and does not move to another.

However, the database enabled object-oriented scanners listed at the start of this article only scan multi-site systems using the Roam method; once an acceptable site is located the scanner stays on that site and only looks for another site if reception is lost. In many areas this causes a great deal of radio traffic on other nearby tower sites to be missed.

The solution is to program each site or group of sites as a separate system so they will be scanned.

Multi-Site Programming

This method applies to any multi-site trunked system but will use Ohio MARCS-IP as an example.

1. Start with a blank Virtual Scanner, define the desired coverage area (for example, Central Ohio), and name the Virtual Scanner as such.

2. Using the "Preferred" options under the Library Import tab of the EZScan software, choose the desired system and select for download all of the desired tower sites and talkgroups for the preferred coverage area. Import this information to the scanner.

3. Name the newly imported system "Ohio MARCS-IP."

4. Set up scan lists and miscellaneous settings (backlight, LED, decode levels, etc) as desired, and do a "save to archive" so you have a backup of your initial programming. The archive will serve as a clean backup in case you have to start over.

5. Copy that system and name the new one Cuyahoga County (using the Cleveland area as an example), and lock out all except the Cuyahoga County simulcast. You can leave the scan lists alone or delete all but the ones for desired agencies in Cuyahoga County. I usually leave scan lists alone so I have a better chance of catching talkgroups which may have roamed away from their usual site.

Next, copy the "base" Ohio MARCS system again, name the new one Lorain County, and lock out all except the Lorain County sites. You can leave the scan lists alone or delete all but the ones for Lorain County agencies.

Repeat this process for each site (or group of sites) you want to treat as separate systems, locking out all but the desired sites for that "system."

Finally, lock out the base Ohio MARCS system, unless you want to use it as a catch-all. In Ohio, I generally leave the "Ohio MARCS-IP" entry unlocked, but lock out all the scan lists in it except one which has the talkgroup Wild Card, so I can search separately from the designated scan lists.

This way you've minimized the amount of stuff you have to type in and the radio will scan each site separately, giving you a much better chance of hearing what you want to hear; when traveling, you can enable and disable scan lists as needed to scan what's around you.

You'll probably also need to fiddle around with the decode settings on the Advanced tab; after I tweaked the DSP Level Adapt setting to 100 (after much experimentation), P25 simulcast decode is almost flawless.

I think you'll find yourself hearing more stuff, more reliably. Works great on a TRX-1.

First thing I learned (the hard way) is that for whatever reason, these things don't like manually entered system settings. When I entered local Ohio MARCS-IP sites manually and put in the talkgroups, I heard very little. However, when I used the Library Import feature ("Preferred" rather than zip code or location based), selected the specific sites/talkgroups and downloaded it, it worked like a champ. Never have figured out why this is the case; control channels, talkgroups and settings were all identical each time, but it just did not like manually entered systems.

Edit: Forgot to mention that you can copy/paste talkgroups and it will work fine. It seems to be just the system-level stuff like sites it's sensitive to where doing Library Import works and manual entry does not. You can just import sites and a talkgroup wild card and get by just fine.