I've had my 300 for about 10 months now, and in the beginning it suffered front end overload issues when using a diamond RH77CA antenna. I had to use the global attenuator always, even with the RS 800mhz antenna. I live in a country setting high up on a hill away from almost everything. I don't even pick up FM radio stations real well here. I do use the 300 a lot, but my PRO-137 is my main scanner as it works the best. But recently I noticed the 300 getting way better on the overload issues. I can actually use the diamond antenna without the attenuator on at all, and it works much better. From where I live I can pick up signals 25-40 miles away from different counties. Has anyone experienced this with their PSR-300, or give a reason why it has gotten better?