Antenna And Radio Overload Question...

[btritch]

I have a GRE PSR 500 radio that I'm listening to my local comms on, However I have it hooked up to an outdoor antenna, A Scantenna actually that's about 45 or 50 feet up on my tower with some other antenna's. It's connected to the antenna and radio with some LMR 400 cable. I have had trouble in the past with it but it's worked pretty good. Well recently in the last couple of days I have noticed, It's not been picking up my local communications, I figured it was from a reciever overload so I went through and turned the Attenuator on the radio on. Well that helped on some comms but again, Most of them werent' coming in at all. I originally thought it was the radio but when I hook up a rubber duckie antenna and turn the attenuator off, It works just fine. So it's either the antenna or the radio or the fact that it's too close to the repeaters to pick up the signals without overloading them, Even with the attenuator set to on. I have noticed it will do this with the CTCSS/DCS codes set. If I set them to search or turn them off, It's not a problem, It picks up everytime on the scantenna. So my question is, If it's overloading the reciever, why will it work with the scantenna and attenuator on if the ctcss/dcs codes are off or not set but it won't work the attenuator on with them set and if it is an overload of the reciever. Does anyone have any suggestions on how to fix this problem?
Thanks!
Brian
Greene County, Arkansas Live Police, Fire, and EMS Scanners

 

[cbadie]

Maybe there is a short in the coax?

 

[moniandre]

Is the overload across all bands ?

I have 2 GRE's and the AIR and parts of VHF-Hi are deaf without an FM trap or notch filter.

 

[kscott]

I have noticed similar behavior with my PSR500 and overload. I believe the biggest issue is that the CTCSS/DCS codes cannot be decoded with a very strong signal and therefore will not open the frequency for listening.

 

[wwhitby]

My PSR-500 has a desense problem on VHF-Hi. Its almost useless with an external antenna for picking up frequencies that don't use a PL/DPL/NAC (like the railroad frequencies.)

From a discussion on the GRE scanners forum, I learned that GRE didn't put in good enough front end filtering on VHF.....

Warren