Greetings Paul,What area are you located in? North is only useful north of the 78, west handles everything south of their and down into metro SD somewhat.
And UCSD Medical Center is on the south site, or are you trying to listen to the campus or Thorton? Are you on the stock antenna indoors or something?
as for my location - I am unfortunately located within 100 feet of the 480 kilovolt? power transmission lines in Imperial County. I am approximately 3 miles from the T-Mobile tower that also has county radio service. The San Diego Imperial county radio waves transmitting on the tower known as Salton City. The Next Gen control channel for audio P25 is 856.1125 Mhz and not the frequency listed on the RR web site. As for which tower is useful for a particular area, this topic is tricky, however, to shine an example - Imp County Sheriff and the City of Brawley are usual radio traffic on Salton City transmitter tower. With that said, occasional traffic from Calexico appears over here at Salton. If the conversation is involved, long enough, a pursuit --- the tower is occupied with Calexico. Therefore, Imp County Sheriff radio traffic and Brawley radio traffic, and even Imp Cnty Fire radio traffic are sent to West Simul, Hendrix Peak, Black Mountain, Superstition Mountain , even though , the non Calexico units are geographically closer to the Salton City tower. Once that concept is understood, the p25 system and it's abilities with be an eye opener.
As for my UCSD facilities comment, I viewed the unit identifiers while radios were in use. The 6 digit id's helped me discover that the control channels for San Bernardino and the radios being used on the San Bernardino system are being received by my scanner.
I researched that Imperial County Fire Tac 6, Calexico Fire Tac 5, and, UCSD Facilities are being received - however - I'm receiving system 37 - San Bernardino and not Imperial County or UCSD.
I am kind of suspicious and thinking, if and when San Diego or Imperial actually start to use the radios on those talk groups -- -- -- will I receive garbled reception because of San Bernardino and San Diego Nex Gen fighting over a particular shared talk group ID or channel?
Kind of sad how the frequency allocation genius decide to allow two counties close together to operate a p25 system, p25 control channels, on the same frequencies. The North Simulcast for San Diego/Imperial and San Bernardino systems are fighting for air wave/transceiver space
as for the antenna - I purchased an outdoor antenna, but, have discovered my remtronix antenna works better than the roof mount IF I walk around the house looking for that receive all sweet spot.