I'd be interested. I run Unitrunker 2 more or less 24/7 on Anne Arundel's SmartZone.
SDS-200...a little underwhelmed
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So I went out on an expedition to check on a few new FIRST site in northern Maryland: the Tower Road site in the Catoctin Mtns., and the site-still-in-progress site in Cherrytown. On the way back, I checked coverage / reception of the Frederick County system, with particular interest in the New Market area. Using three different radios and antennas: SDS200 with a 3db roof mount antenna; Unication G5 with the purple antenna; and Unitrunker 2 with a Nooelec SDR and cheap on-glass antenna of questionable quality. All three radio / antenna combinations had no issues receiving the Frederick County system on a route from Lake Linganore south into New Market, past Station 15, and out onto I-70. In fact, the RSSI is stronger than average in the area, and decode quality measured with UT2 never wavered from 100%, even when using a **** on-glass antenna. I suspect the op has a configuration / programming problem. I'd suggest do some further testing with a profile only containing the Frederick County system, and lock out the Brunswick multicast site which is way far away (and its range in the RRDB is set too big at 15 miles; it should only be about 8 miles since the antenna is mounted on a water tank.) A yagi is definitely unnecessary to receive this system using a SDS radio.
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Should have added that the New Market site at I-70 is a direct line through my house from where i'm able to put an antenna, and through a hill...I have a much clearer shot at the WQYL254 tower with the yagi. At the moment my VHF antenna selections are limited...the whip, the yagi, or a DJ-130.
I might have to look at other antenna options....
I've locked out the Brunswick site, and whittled down the channels on the Frederick system to just the control and alternatives. That seems to help, but i'm still having better luck w/ the DNR and JNCR channels than I am w/ Frederick....
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So I did an experiment this am. I put the telescoping whip that shipped w/ the Uniden on the RTL-SDR running OP25, and connected the SDS-200 to the yagi. The RTL-SDR is pulling in probably 80% more traffic than the Uniden, even though the Uniden is seeing the signal...apparently it has trouble doing the decode. This is with the radio locked to the department of interest, so it's not a timing issue (and my favorites list isn't that big anyway). Note I've done the reverse as well....Yagi to the RTL-SDR and whip on the SDS-200; same results.
RE: filters....invert (whether normal or wide) results in no signal on this site. Normal and wide appear to work.
The only other thing I could think of would be if the SDS-200 isn't seeing all the TG, but I built the freq. lists for OP25 from RR, and I just updated the db on the SDS-200 so....
RE: filters....invert (whether normal or wide) results in no signal on this site. Normal and wide appear to work.
The only other thing I could think of would be if the SDS-200 isn't seeing all the TG, but I built the freq. lists for OP25 from RR, and I just updated the db on the SDS-200 so....
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This might be a silly question....but are the frequencies listed for each site just the expected control frequencies (or are they also the voice frequenicies)? For my OP25 setup, I just used the control frequency of the site closest to me (854.9875 MHz). I'm wondering if perhaps the issue i'm having is that for whatever reason the SDS200 is trying to lock on a less than favorable control frequency. If that's the case I could just edit out all the others....
Seeing how i've got Sentinel up and running now i might as well give that a try
Using RR's database the primary control channels (frequencies) are in red and the alternate control (used when the primary is down) are in blue. Normally in my experience (on Michigan's MPSCS) with a Uniden scanner you only need to program the primary channel for each system, but it's a good idea to include the alternate as well. Programming voice channels might screw up following a trunked system properly.
You should always program the alternates. The radio doesn't care, and cch do roll from time to time.
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If you want to send me your current programming, I'll look it over. I use a regional Favorites list and location based scanning with a GPS since I am mobile and don't like making adjustments when driving. This way I control the configuration, and don't waste processor time trying to tune what is not receivable - all I need to do is turn the radio on and off, adjust volume, and set occasional holds. I'd also double check Service Types to make sure what you want to hear is enabled. I did notice in your screen shots that your RSSI borders on marginal, yet should still be serviceble.
Always remember that a strong close by signal with rf overload will not decode properly. Weird quirk of digital radio.
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