ScanDiego.com

What talkgroups should I be putting in for RCS East besides CHP, SDSO Rural, and the East county fire stuff? A couple weeks ago I was in El Cajon and put the RCS East into scan mode mainly heard CHP and SDSO. I also noticed Imperial County Sheriff was simulcast on 39472. Is this common or just a rare occurance? I'm going to be in El Cajon tomorrow and plan to update my scanner with RCS East info before going.
Thanks for any suggestions.

I also have:

SDSO Santee Dispatch & Tac-50
SDSO Imp Beach / Lemon Grove Dispatch & Tac-60
El Cajon PD - all
La Mesa PD - all

EL CAJON pd
La Mesa PD
Lemon grove SO
ARE NOT on the east simulcast

Santee SO because of alpine will be on occasion all the SDSO 80 rural units will and poway because of the patch ICSO will be on the EAST too