I have a SDS100 and 200, and have tried (just about every antenna imaginable,)
and it is so frustrating, as the reception is very weak / unstable...
Has anyone (in my area) experienced this, and could you find me any advice?
When you say you have tried about every antenna imaginable, does this include outdoor antennas?
If not, that's probably what you will need being in the SW corner of the county.
The hills around you really knock the signal levels down from the VHF Moswin sites.
How is your elevation compared to the surrounding environment close to your home? Things like trees or tall hills between you and the VHF Branson site?
The Ozarks always were a problem for the state. Those hills are what allowed the state to obtain such high power limits for their low band licenses back in the day. They basically brute forced the low band signals through the hills using high power levels.
You may need a VHF yagi aimed at the Branson site and possibly a good quality low noise preamp. I'd try and make it work without a preamp though as preamp's can ruin a digital signal, especially a weak signal.
The good thing is the VHF Moswin sites are not simulcast so that's one problem you don't need to mess with.
On the SDS models, the Invert filter choices both reduce the available signal level. The Normal filters don't reduce it as much but still attenuate the signal a small amount.
Have you tried the site with the Filter setting set to Off? That may be worth a try if you are in a rural area without any other high power transmitters near you.
I also had issues with the Weldon Spring site here before. I found that forcing the radio to use FM mode instead of the default NFM mode really helped with the reception of that site for me. Once I put up decent VHF antennas on the roof, I was able to go back to NFM mode.
