Don't worry....you're not the only one with that problem.
I live further up north from JC, but was able to get the cops and fire digital system with basically no problem (analog is OK).
Now, I can't get them at all.
I've did a test within JC, driving up JFK with a hand-held scanner, while also monitoring JC on my phone. The signals on the scanner stopped just south of 495. I would imagine that a Motorola radio would do better, since there's no complaints from the police or fire field units (then, again, how would they know they were NOT receiving a signal?).
I also did a test on southbound River Road. No signal until about the area of Palisades Hospital. I also tested on southbound Tonnelle Ave, with no signal as far down as 79th St., at which time I gave up and went up to JFK northbound, with no signal there, either.
The problem seems to be with the massive development of high-rise buildings, especially in the Journal Square area. Don't expect anything to change, however, until a LOT of complaints come in from the police and fire units.