Sdrtrunk in Mahoning County

[DS506]

Installation Summary
40' telescoping mast
D130J Discone, Channel Master Stealth directional TV antenna (adjusted for the best TV reception at about 70 degrees), Bonito Mini Whip.
Amps at the base of the tower
Listening post in the basement connected by 120' of RG6 cables so I can select which antenna I feed to the radios.
GRECOM PSR-310 (handheld)
4 RTL-SDR dongles, SDR#, sdrtrunk (at home only)

I installed sdrtrunk last week, and loaded the MARCS, Austintown/Boardman, TRIconnex, and Staley systems from RR. Took me a number of days to get sdrtrunk to display any action let alone HEAR anything.

Now I can easily/repeatedly pull up TRIconnex and listen to a TAXI TG and an unlisted TG (I have a hunch who that is). That tower is 7 miles away. Gives me hope for other trunked systems!

The Staley system, as others have said, is about defunct. I have picked up traffic on 2 frequencies attributed to Staley using the PSR310 on the road but nothing at home or on SDR# or sdrtrunk. I believe Staley is on the same tower as TRIconnex.

Of most interest is the Austintown/Boardman system. 10 miles. I can hear the control channel and digital voice channels on the PSR310 or sdr#. While I was trying to get ANYTHING to work in sdrtrunk, I did see in the Events tab, 5 or more department talk groups hit, some showed as encrypted, but never had audio. I deleted and rebuilt the A/B system many times and have never been able to see TG's again. (I need to remember instead of deleting and starting over, to clone it and keep an "old" version if something works at all.) I would think I would be able to hear some TG's as RR shows only half are fully or partially encrypted. The current setup I have the Source as the control channel. I have also tried listing multiple/all the channels. I have tried both a preferred tuner and none. Decoder set to P25 Phase 1, Modulation C4FM. I have tried LSM as well. I have set Ignore Data Calls on and off. I have it logging everything. For Alias, I have imported all talkgroups, set all to listen. I have tried only a select group. Also in the tuner menu, I have tried auto and manual gain in many variations.
WHAT AM I MISSING?

Brings me to MARCS. Nothing heard or visualized on the scanner, in sdr# or sdrtrunk. I plotted the 12 nearest towers. The first three are;
8 miles at 210 degrees
14 miles at 240 degrees
15 miles at 70 degrees.
I imagine lower power and simulcast is hurting me here especially using the discone. While the TV antenna is pointing in the correct direction (70 degrees) for one of the sites, it does not cover 7/800 MHz. I tried it anyway - nothing. Heck I even tried the mini-whip which is meant for below 30MHz. I thought I could see an improvement in SDR# on the control channel, but I certainly could not hear any change.
Anybody think a 7/800MHz Yagi would pull a signal out of nothing?

 

[northernsummit]

Anybody think a 7/800MHz Yagi would pull a signal out of nothing?

Yes. I have a 10-13db gain yagi pointed at a tower 3 miles away feeding 8-10 RTL-SDR's through a splitter (which has insertion loss). The yagi is tuned to the middle of the system's 800mhz channels. I don't know if you can make a yagi that would work on both 700 and 800 - you may need one for each band and dedicate different dongles to the respective bands.

 

[sonm10]

120' of rg6 gives you 10 db of loss. Probably need to upgrade to better coax - MINIMUM LMR-400 or LMR-600 would be better. Might need some sort of LNA to.

 

[tweiss3]

Don't forget, for SDRTrunk to turn signals to audio, you need to configure the JMBE audio library under SDR trunk preferences.

 

[DS506]

Don't forget, for SDRTrunk to turn signals to audio, you need to configure the JMBE audio library under SDR trunk preferences.

Yes, have the same file.
Might be a few days, but I will take the laptop and dongles out to the base of the tower and see if bypassing 120' of cable shows any improvement

 

[DS506]

Had the opportunity to get outside today with the gear at the base of the tower.
Direct off the discone roughly 36 feet of cable (no amps). Success!
Austintown/Boardman system. In the details tab of SDRTrunk, populated info on the current site including call sign. Many aliases showing up in the events tab. Austintown, Beaver, Boardman Canfield, Campbell, Youngstown, YSU, Poland, MCSO. Some encrypted as expected. Hearing audio of those that were not encrypted.
Better signal off the Salem MARCS tower. The control channel was significantly higher than the noise floor. Nothing in the events tab. In the details I was seeing what seemed like errors rather than Sync loss. Caught a few words as it was scrolling (OSP, Vendor followed by a number or a few names).
7/800MHz Yagi on order.

 

[DS506]

Update. When the Wilson 7/800 Yagi arrived, I unboxed it and for the heck of it, connected it to the SDR's in the basement. It works! So I hung it from the rafters pointing out a window in the direction of the tower with only 20 feet of cable and it picks up the Austintown/Boardman site great!
Tried aiming it toward the local MARCS towers with no significant improvement.