The 396 and 996 BCT15, and probably the 246 and 330 use a different cable from the other scanners listed. The 250 and296 share a cable, and all of the programmable mobiles use a DB9 Male to DB9 Female (just a plain old serial cable). For the 996 and BCT 15 you need a null modem in order for the serial port on the back to work.
I own or owned at one point Bearcat 780, 785, 796, BCT15, 996, 396, 250, BCT8, and 296 scanners. Since I computer program all of them, I have a pretty good handle on what cable fits what scanner. If Pinnellasfirefighter can get his 250/296 cable to work in any other scanners, I'll be very impressed.
Gary