Prince William County STARS Site 001-018

Status
Not open for further replies.

BM82557

Member
Joined
Aug 28, 2006
Messages
5,117
Location
Berkeley Co WV
I noticed this morning that STARS site 001-018 Independent Hill is using 158.8125 as the control channel. Getting a good decode showing NAC 190 TGS 3, 17 and 67 have been in use. The RR DB lists 158.8125 as a voice freq so I'm not sure when the switch took place. UniTrunker shows 152.5475 as being an alternate CC. 151.3700 is in the RR DB as being the alt CC but UniTrunker shows it as being an voice freq. The other freqs match with the exception of 159.2250 not showing up in UniTrunker at all, it is listed in the RR DB as an voice freq but UniTrunker shows it having been replaced by 159.1200.
 

dlwtrunked

Member
Premium Subscriber
Joined
Dec 19, 2002
Messages
2,348
I noticed this morning that STARS site 001-018 Independent Hill is using 158.8125 as the control channel. Getting a good decode showing NAC 190 TGS 3, 17 and 67 have been in use. The RR DB lists 158.8125 as a voice freq so I'm not sure when the switch took place. UniTrunker shows 152.5475 as being an alternate CC. 151.3700 is in the RR DB as being the alt CC but UniTrunker shows it as being an voice freq. The other freqs match with the exception of 159.2250 not showing up in UniTrunker at all, it is listed in the RR DB as an voice freq but UniTrunker shows it having been replaced by 159.1200.

What seems to not be known by many is that every so often, many trunked systems change their control channel set. This appears to be true of most trunked systems that I know. In theory, any channel in a trunked system could be used as the control channel. However, it appears in reality probably due to programming limitations, that at any one time, only a limited number of channels in some systems can be used as such. The rotating of control channels is done to spread transmitter use time. Naturally if only a subset of the frequencies do that, one does not succeed in doing that unless one changes that subset occasionally. for this reason,from my point of view for listening purposes, identifying frequencies used currently for control channel is just an invitation to inviting obsolescence of the information.

Additionally, I have seen systems (IWNS), where a site has a set of frequencies but apparently not enough transmitters to use all of them. So at any one time, only some are in use for control or trunk. Then every so often, is uses a different subset of those frequencies. Over time one can determine the set.
 
Status
Not open for further replies.
Top