This maybe asked/answered, but I haven't found it. In a county like Cook, how do I know which tower(s) to program for ISP. I live in Du Page and it's easy, one tower, one set of freq's.
Thanks in advance, Rich
Thanks in advance, Rich
Multi Tower counties.
- Thread starter Linneweh
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Multi Tower Counties
For ISP the Starcom21 listings in Radio Reference are where to find what you need
STARCOM21 Statewide Illinois P25 Trunking System, Statewide, Illinois - Scanner Frequencies
THIS map shows the ISP Starcom21 tower numbers for the one closest to you.
http://wiki.radioreference.com/images/7/72/Starcom21_Site_Numbers_Map.jpg
For ISP the Starcom21 listings in Radio Reference are where to find what you need
STARCOM21 Statewide Illinois P25 Trunking System, Statewide, Illinois - Scanner Frequencies
THIS map shows the ISP Starcom21 tower numbers for the one closest to you.
http://wiki.radioreference.com/images/7/72/Starcom21_Site_Numbers_Map.jpg
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Make sure you understand the concept of simulcast as well. When you see simulcast listings consider each tower in the group as part of the whole. All towers on a simulcast site share the same frequencies so you only need to program it in once.
Cook County is kind of odd in that it has 2 separate StarCom21 sites as well as several Cook County owned sites. Since Cook County is encrypted there usually is no point in monitoring the 500 series Cook County sites. The rest is geographic. If you are north of the Ike then monitor Site 149, south monitor 102. If you are more centrally located then monitor both.
Most other counties have a single site or a single simulcast group. There are some places that have multiple independent sites, such as the Springfield area.
Also remember that just because a site is in one county it will likely carry traffic from neighboring counties. Radio signals do not respect county lines.
As a rule of thumb I draw a circle around my location and program in any site within that circle. I arbitrarily choose what I think is an appropriate range for the dimension of my circle. 25 miles is my usual choice. Any tower in that 25 mile circle goes in the radio.
Cook County is kind of odd in that it has 2 separate StarCom21 sites as well as several Cook County owned sites. Since Cook County is encrypted there usually is no point in monitoring the 500 series Cook County sites. The rest is geographic. If you are north of the Ike then monitor Site 149, south monitor 102. If you are more centrally located then monitor both.
Most other counties have a single site or a single simulcast group. There are some places that have multiple independent sites, such as the Springfield area.
Also remember that just because a site is in one county it will likely carry traffic from neighboring counties. Radio signals do not respect county lines.
As a rule of thumb I draw a circle around my location and program in any site within that circle. I arbitrarily choose what I think is an appropriate range for the dimension of my circle. 25 miles is my usual choice. Any tower in that 25 mile circle goes in the radio.
Thanks N9JIG, that's what I was asking. When I travel, I monitor ISP for that area, so getting the correct tower for ISP, both location and radio traffic, is what I was asking about.
Thanks again, Rich
Thanks again, Rich
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