Never thought of that! I do have Close Call on my scanner.If you have the phone number you can try a reverse lookup on white pages dot com and see to whom or what company name the phone number is listed to. Once you have that info again try another fcc db search.
EDIT: Another method if you have a close call feature in a scanner or if you have a portable frequency counter is to park near this Millburn Ave address and observe the building as they should have an antenna of some sorts or at least be using a two way radio so perhaps you could lock onto the freq that way.
EDIT2: Its also possible they may be using cell phones if they could not obtain a license due to lack
of frequencies available.
EDIT3: Some taxi cab companies lease air time from communications companies on the shared
repeater or LTR systems they may have so they may be using such a system.
I'll give that a shot if I can do it without looking like a terrprist scanning for info!I have confirmed hearing a Taxi Company serving the Essex county area on 157.630 MHz. Perhaps that's them! Let me know if it is. A good idea is to just drive near the company's headquarters, park your car nearby, and see if you can pick them up using the close-call option on your scanner. That's how I got several of my frequencies in the past. I've found that many taxi companies do not license themselves with the FCC and/or they buy radios from radio rental companies. For example, Linden Yellow Cab isn't listed in the FCC database, however they do use frequencies in the 504 - 505 MHz range from a recent close-call I captured on my scanner.