NXDN is continuous.
Close Call works fine on DMR and NXDN systems. Please note Close Call will not capture a DMR handheld/mobile. A real antenna (e.g., mobile antenna) will greatly increase the chances of Close Call finding a transmission.
Please give me a link to an antenna I can buy now that is in stock. And you mean one for the radio not one for the car? I wouldn't mind either. I'm in my company vehicle 8 hours a day 5 days a week. I have yet to have a vehicle check. They definitely wouldn't notice. Hehe.
I'd go for both, as both are in wide use. (Actually, each gives you several related systems, so having both DMR and NXDN, along with P25, gives you quite a wide range of digital modes, both conventional and trunked!)
There are numerous good antennas for your scanner, such as those made by Remtronics and Comet. Make sure it's an SMA connector. (I use a Comet W100RX.) You'll be amazed by the difference from the supplied stock antenna! (A very common misconception of Uniden scanners is the poor performance, without taking into account that the stock antennas that come with them are often the main culprits.....)
There's a reason to why there are hundreds of different antennas to choose from. If one where the best for all scanner/radios and frequency bands and situations then that would be the only one sold. But that are not the case so it will depend on different factors which antenna that would work best for you. The same can be said for a lot of things, like cars. If one car where the best for everyone then the majority of people would buy that specific car, but there isn't a one-fit-all vehicle.
