It looks like Skipp and I have found that the GLB preselector has been successful at helping "less then ideal" repeaters work better. I can think of two examples that I have had.
I had a Midland 13-509 repeater back in the late 80's on 223.72MHz. It used a set of homebrew copper pipe duplexers. The duplexers would drift with temperature swings, but by adding a GLB preselector I was able to add enough additional rejection to make the repeater play quite nicely. I also had a UHF Maggiore repeater that used an antenna at 450 feet on the top of a tower. I was being plagued by occasional desense that I was never able to track down. It never seemed to happen when I was at the site. By adding the GLB preselector I was able to reject whatever it was that was getting past the duplexers and solve the problem. My point is that the GLB is not just something to add to a repeater to make it have a hotter receiver. The BIG advantage is that you can get a bandpass characteristic with very tight skirts that will help a receiver that is passing too much crap through it's front end. You can also get this in a very small package that will fit in an area where you don't have room to hang a big cavity filter on the wall. The GLB is not the answer for everybody, but it has it's place. 73, Joe, K1ike
