One thing to keep in mind, a dedicated business band radio _usually_ has better sensitivity and selectivity. To compare a scanner to any commercial radio probfably is not realistic.
Also, depending on the frequencies you are listening to, the default antenna may not be up to snuff. I routinely purchase antennas that are specific for the band I will monitor the most.
I don't own a PSR-300/400 so I can't vouch for its sensitivity, but if it's anything like it's big brother it should have great sensitivity across the board (at least when compared to other scanners).
If I were you I'd make sure you don't have the ATT (attenuator) turned on, either globally or on individual frequencies (if the radio has an ATT - and i imagine it does).
If I were you, I'd also consider swapping out the antenna with an antenna for the band you are mostly wanting to listen to (although that would mean a sacrifice in performance on other bands).
I think it's too early in the game for you to be objective enough regarding the scanner - You have to take into consideration what you are comparing it with as well as use an antenna that is specific for the bands you want to listen to.
I rarely ever use the stock antenna on any scanner.
Mike / AA8IA
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