Monitoring Cedar Rapids and the surrounding area through the Linn County Simulcast.
Operator: Scott Abing
Location: Cedar Rapids, IA
Linn County, Iowa, fire and EMS live audio feed including Cedar Rapids and surrounding communities. My goal is to include useful unencrypted SARA network talkgroups from the Linn County Simulcast, I have blacklisted encrypted police and sheriff traffic along with unencrypted operations communication, leaving mostly fire and EMS in the stream. I also include any police or or sheriff dispatch communication which is unencrypted. I provide this stream as a public service in my spare time for the betterment of the community.
New in 2023!
I'm currently phasing in new software which is providing higher quality audio decoding and a more complete representation of all the radio communication taking place on the Linn County Simulcast. This new software is called SDRtrunk and runs on more powerful hardware and utilizes 4 tuners running simultaneously across the spectrum of the simulcast. You should notice much tighter communication with fewer dropped calls especially when things are very active - this is due to an advanced tuning and queuing system which will que concurrent calls chronologically into the stream rather than just dropping them when things are most active. Please bear with me as I test and roll this out and always email me if something is wrong for more than a few minutes - firstname.lastname@example.org
2/2/23 After testing I have moved to a version of the software which is older and more stable - SDRtrunk version 0.5.0 Beta 3. As far as listeners go I do not think this has any impact. I will no longer be restarting the app twice each day and will determine what is needed as I monitor long term stability. I have also relocated the iMac to a rack in my basement where it will permanently live on battery backup. Thanks for bearing with me through the upgrade.
1/27/23 I will now be restarting the scanning app at 1:30AM and 5:30AM each night. The restart lasts about 15 seconds and will briefly interupt service but ultimaterly should lead to the uptime we are all looking for while I wait for the dev to fix the memory leaks in the code.
1/24/23 Stability issues with the software continue and it is a known documented issue with the dev. I am now restarting the app automatically every 12 hours which means you may need to tap the "play" button on some listening apps after it restarts. The restart will lead to a 15 second outage twice daily but should ultimately lead to the service being up reliably. This is a temporary solution.
1/22/23 Updated software to the patch release of SDRtrunk in order to chase the stability issues we had yesterday. Each SDR has also been relocated to it's own separate USB host which is supposed to help with stability. The goal is for this to be as reliable as my previous setup which would run for 3-4 months continuously without issue.
1/22/23 New battery backup ordered for longterm install of the current tuning system.
1/21/23 Software dropped the control channel and we had silence for about 4 hours early this morning before I was able to get things reset. I'm still diagnosing and looking at settings I can change and a different configuration for my SDR's since I need this to run unattended 24/7.
1/20/23 After some listener feedback I went ahead and added another SDR to the system making 4 in total.
1/19/23 Just went live on the Broadcastify Calls platform which is the future of providing the best access to this communication. This is something you must experience if you love scanning and want more control over the feed I provide - my node is here - https://www.broadcastify.com/calls/node/2149
1/18/23 Purchased a used iMac from a wonderful gentleman in North Liberty to up the processing power of my scanning source computer. I have also now added a 3rd SDR tuner to the mix which will allow for an even more thorough scanning setup. Software stability for the long haul is still being tested so please bear with me and email if you notice an issue lasting more than a few minutes.
1/18/23 Software stopped tuning correctly which lead to radio silence in the stream. I'm going to keep watching it to see what the problem is as I move everything to new hardware (again)...
1/18/23 24 hours later and it's still on the new software and I have received no complaints which is basically as good as compliments! So far it has been a relatively seamless transition. Most of these changes should be very subtle to listeners but on the backend it's like a heart transplant.
1/17/23 Launched on new SDRtrunk software utilizing multiple tuners on Apple hardware and will be monitoring closely to finely tune the system. There may be a few momentary outages lasting 10-20 seconds as I get the software dialed in.
1/16/23 Listeners peaked at 275 for the Tornado Warning weather event.
3/7/22 Metadata updates (new alpha tags)
3/7/22 System is back up after an outage lasting about a day and a half. I was unable to fix a software issue remotely so the system was offline until I had physical access. This is the first outage lasting longer than a few minutes which I can't blame on any of my service providers.
1/4/22 User Justin contacted me to let me know there was a TG blasting some undesirable chatter. I have blacklisted the TG to make the stream more listenable.
12/15/21 Over 300 users listening with the weather event taking place - I will do my best to keep the stream online if it gets ugly.
7/4/21 user reported issues, system reboot was necessary to bring everything back online correctly
6/14/21 Metadata updates - added around 70 new talkgroup ID's
4/2/21 Listeners peaking around 50-60 per day on weekends over the past few months! I'm glad to see this project benefiting others. Honestly, I have put this on autopilot for the past 4 months and the thin client running linux and OP25 has been rock solid. Please provide feedback if there are things which need to be addressed. I respond to email and if there are requests for changes which make sense then I take action.
12/14/20 Metadata updates - added around 100 new talkgroup ID's
12/14/20 User Brian asked about an unidentified talkgroup which lead me to pull the latest info into my metadata spreadsheet.
12/3/20 User Joel checked in with some questions about programming his scanner
11/28/20 Network upgrades today, service will be up and down, will keep it up as much as possible.
9/15/20 While I was on vacation a few users notified me that the feed was garbling. I rebooted remotely initially and now I've updated to the latest version of OP25 and moved the installation to an old thin client. So now on different hardware and software. There is still some slight garbling at times.
9/6/20 Another power outage resulted in the feed going offline as mediacom service went down. The stream is now running on backup power over verizon until power is restored and mediacom comes back up.
8/16/20 I was unable to secure a reliable data connection needed to keep the stream online after the unprecedented wind storm that hit Cedar Rapids on 8/10/20. As an aside, my house took roof & water damage along with the antenna mast snapping in half. My primary internet provider, Mediacom, went down when they lost power and my backup, Verizon, did not provide the stable bandwidth needed to get the stream to the server. On 8/16/20 Mediacom service was restored to my house thus allowing me get the feed going again.
8/5/20 Now using outdoor omnidirectional antenna feeding this feed and the secondary feed.
7/11/20 The scanner software has been configured to automatically handle control channel frequency changes
7/9/20 The raspberry pi scanner has now been up for over 45 days without interruption in service to broadcastify. I will keep providing the feed and focusing on uptime as a priority. I welcome your questions, comments or concerns.
7/8/20 To follow up on a previous note about audio quality and adding a directional antenna; I did purchase yagi antennas and conducted testing, but determined there was no appreciable gain in the decoding quality. So the main feed is still using a basic omnidirectional antenna and receiving signal from multiple towers in the simulcast system. Originally, a user had complained of occasional garbled audio; the best that I can determine is this is brought about by a combination of irregular signal quality into the simulcast system and the method of error correction employed by the OP25 software. After contacting the lead dev of the software, trying multiple antennas, SDR's and PI's all yielded the same result, I’m going to move on. I feel the audio quality is generally pretty good and not bad at all for free software on a $40 computer… Always open to any suggestions or a free SDS100...
7/7/20 Eric who is running a new feed for Johnson County contacted me. I haven't listened yet, but if there is a reliable and consistent JC feed up now, I will start to eliminate some of the JC chatter from this feed.
6/10/20 Daily listener count is now around 50
6/9/20 Broadcastify had some issues today, they reported an outage at 6:02pm and reported it fixed by 8:23pm - this was reported as an issue with their hosting provider and some issues continued past their reported fixed time. In other news, I'm configuring a server for streaming secondary feeds and already have it in testing. More on that soon...
6/8/20 New undocumented tg 52022 has been blacklisted since it is encrypted.
6/8/20 Identifying 50006 as IA TAC 6 until an official name is given. This seems to be Iowa State Patrol communication for multiagencyinteroperation and is being used in the Iowa City Area.
6/7/20 User Tom checked in to compliment me on the feed and inquired on how I'm able to scan nonprogrammed talkgroups like we had last night with 50006. See new note at the very bottom of this info.
6/6/20 Undocumented talkgroup 50006 popped up tonight with communication around the Iowa City Protests so I'm temporarily calling it "Iowa City Protest" but it is likely a state or regional tactical interop communication talkgroup like 50002 IA TAC 2.
6/6/20 Keeping all IC protest unencrypted communication available
6/6/20 Blacklisted 50002 IA TAC 2 due to out of area communication - will consider for inclusion in secondary feed.
6/6/20 Blacklisted 16406 UnityPoint Amb due to out of area communication - will consider for inclusion in secondary feed.
6/6/20 Blacklisted 57905 VMED28 Patch & 52034 VMED28 - will consider for inclusion in secondary feed.
6/6/20 - Blacklisted 57902 VLAW31 Patch & 57903 PT to PT Patch, BH talkgroups 40703, 40702, 40710, 10703, 10704, 10705, 10702, 50721. - will consider for inclusion in secondary feed.
6/5/20 - Blacklisted hospital talkgroups eliminating ER communication - will consider for inclusion in secondary feed on my own server.
6/1/20 - User kodka11 inquired about the hardware config and also wanted me to be aware of the Broadcastify terms of service which I have been disregarding to include ER communication during the COVID-19 outbreak.
6/1/20 - Users peaked at 297 with the heightened awareness around potential looting and civil unrest.
5/28/20 - A user n0zjt complained about ER communication and system maintenance talkgroups inclusion in the feed.
5/27/20 - A user Alex Langer has complained of anomalies in the audio, to address this I will be purchasing a directional antenna. The assumption is these warbles or hiccups could be related to receiving from multiple simulcast towers. I feel it is listenable in its current form but will explore this option to see if I can do better for the users. Upgrades are expected around June 3rd, 2020.
5/24/20 - At peak there were 37 listeners today, the most since coming online 1 week ago. The new headless pi4 has now been running without issue for 48 hours and looks to be stable.
5/23/20 - Retimed alpha tags in an attempt to better synchronize with the audio.
5/22/20 - Service taken offline briefly at midnight to swap hardware and enable alpha tags. You will now see talkgroup ID's when the scanner is latched on a talkgroup. I have moved everything to a headless pi4 device for uninterrupted 24/7 operation and will monitor stability. Now using liquidsoap as the streaming application for op25.
5/19/20 - Service is stable and the stream is made public
5/17/20 - Service brought online for testing - cake day!