If the 300 your asking about is the Stereo SA-300, Sure, shouldn't be a problem. The 202-T is a tuner preamp. As it was originally designed for the Extinct Crosby Multiplexer, you'll have to use an external GE/ZENITH format Multiplexer like the FISHER MPX 100 or the console version MPX-200. But any brand external multiplexer will work with it.