KB8TZX
Member
Hello, again, everyone!
I figured since my other posts on more specific issues evolved into troubleshooting, or discussion of, my receive setup that I would just open another thread to keep the other threads less confusing. (For reference, one of those posts was:
http://forums.radioreference.com/ar...1036-maricopa-mcso-lcns-white-tanks-help.html
To reiterate some things and save all that bouncing, I am running a dual SDR (R820T USB TV tuner) setup utilizing SDR# (SDRSharp) as my radio software, the UniTrunker software to handle the trunk-tracking, and DSD+ (or DSDPlus, if you prefer) to handle the digital voice decoding.
I started exploring the local systems and have had a great deal of success hearing many of them with no issue. However, due to my specific location, I am unable to hear most of the really "local" activity due to multipath interference/distortion while receiving Simulcast G on the RWC. As my specific end-goal interest was to be able to listen to (and potentially stream) the talkgroups for El Mirage PD (4330) since it is essentially my back yard and no stream yet existed, this has been the bane of my existence since beginning this project. As I have learned here, their TG is only on this Simulcast and no others.
Initially, I thought I had found a nice (but temporary) solution in a home-brew dual Yagi-esque contraption I built (see: http://forums.radioreference.com/arizona-radio-discussion-forum/281988-improve-rwc-reception.html for more on that). The control data indicator in UniTrunker was "unhappy red," but UT was still tracking reliably, and the audio from my control receiver was easily and clearly decoded, after disabling the AGC and decreasing the receiver gain, unlike I had experienced previously. I re-did the whole thing with better wire, too, as an intermediate step to building a more permanent version given the results I thought I had achieved.
Sadly, there must have been confounding variables (weather affecting propagation, system issues, etc.) that allowed this arrangement to work so well. I have been able to get "improved" reception since then compared to the (included) vertical alone, but I am still having multipath issues that make the voice channels grossly unlistenable.
After some great information provided by others here on RR, I was able to dig up the site locations for the simulcast and did some crazy calculating with online tools to determine my air distance and heading to each one. I now see where some of my difficulties are coming from (assuming this contraption has a beam width of 30 degrees, anyway). One site is 5.2 miles away, another 6.5 miles with bearing of 285 and 254 degrees (perhaps reversed).
At this moment, I am considering the possibility that I will have to get a bit more involved in finding a "solution" to this issue in the way of not only building a real Yagi, but building a stack of 2 in order to get the beam narrow enough to deal with the interference.
So there is where the project sits for the moment, stalled by budget for antenna building supplies (minimal as these would be) to test my latest notion and lack of other creative ideas.
First of all, is there any merit in attempting the Yagi stack in all practicality - especially a homebrew array? Also, anything you can share to assist in making this thing functional would be fantastic, and my thanks to those who have already offered their input!
Dave
KB8TZX
I figured since my other posts on more specific issues evolved into troubleshooting, or discussion of, my receive setup that I would just open another thread to keep the other threads less confusing. (For reference, one of those posts was:
http://forums.radioreference.com/ar...1036-maricopa-mcso-lcns-white-tanks-help.html
To reiterate some things and save all that bouncing, I am running a dual SDR (R820T USB TV tuner) setup utilizing SDR# (SDRSharp) as my radio software, the UniTrunker software to handle the trunk-tracking, and DSD+ (or DSDPlus, if you prefer) to handle the digital voice decoding.
I started exploring the local systems and have had a great deal of success hearing many of them with no issue. However, due to my specific location, I am unable to hear most of the really "local" activity due to multipath interference/distortion while receiving Simulcast G on the RWC. As my specific end-goal interest was to be able to listen to (and potentially stream) the talkgroups for El Mirage PD (4330) since it is essentially my back yard and no stream yet existed, this has been the bane of my existence since beginning this project. As I have learned here, their TG is only on this Simulcast and no others.
Initially, I thought I had found a nice (but temporary) solution in a home-brew dual Yagi-esque contraption I built (see: http://forums.radioreference.com/arizona-radio-discussion-forum/281988-improve-rwc-reception.html for more on that). The control data indicator in UniTrunker was "unhappy red," but UT was still tracking reliably, and the audio from my control receiver was easily and clearly decoded, after disabling the AGC and decreasing the receiver gain, unlike I had experienced previously. I re-did the whole thing with better wire, too, as an intermediate step to building a more permanent version given the results I thought I had achieved.
Sadly, there must have been confounding variables (weather affecting propagation, system issues, etc.) that allowed this arrangement to work so well. I have been able to get "improved" reception since then compared to the (included) vertical alone, but I am still having multipath issues that make the voice channels grossly unlistenable.
After some great information provided by others here on RR, I was able to dig up the site locations for the simulcast and did some crazy calculating with online tools to determine my air distance and heading to each one. I now see where some of my difficulties are coming from (assuming this contraption has a beam width of 30 degrees, anyway). One site is 5.2 miles away, another 6.5 miles with bearing of 285 and 254 degrees (perhaps reversed).
At this moment, I am considering the possibility that I will have to get a bit more involved in finding a "solution" to this issue in the way of not only building a real Yagi, but building a stack of 2 in order to get the beam narrow enough to deal with the interference.
So there is where the project sits for the moment, stalled by budget for antenna building supplies (minimal as these would be) to test my latest notion and lack of other creative ideas.
First of all, is there any merit in attempting the Yagi stack in all practicality - especially a homebrew array? Also, anything you can share to assist in making this thing functional would be fantastic, and my thanks to those who have already offered their input!
Dave
KB8TZX