Aug 06 2015

NF9K Indianapolis Repeater Update

This evening the following tasks were accomplished:

1). Firmware upgrade to R02.40.12
2). Installation of EID (license) for OTAP (over-the-air-programming)
3). Frequency change from 441.025 to 442.450
4). Retuning of the duplexers
5). Identified and remediated a bad hardline connector that was causing SWR issues.

Repeater is back up and running! More on OTAP coming soon….

Aug 05 2015

New Frequency – NF9K Repeater, Indianapolis

The Indianapolis NF9K Repeater will be changing frequencies. We received the official coordination from the IRC at the end of June. Due to my trip to Spain as well as the need to coordinate on-site resources, we’re just now getting this done.

Old Frequency: 441.025+
New Frequency: 442.450+

All other aspects (color code, talk groups and time slot configuration) will remain the same.

This change is scheduled to take place Thursday evening, August 6th, 2016. The work will commence around 15:30 and we anticipate completion by 17:30.

If you require assistance with reprogramming, let us know!

Jul 25 2015


Apologies for the lack of updates over the last few weeks.  I’ve spent two weeks in Madrid, Spain for work, came back to work on standing up the Monrovia DMR repeater, which of course facilitated code plug updates, etc.  Here’s a short update on what’s cooking, with more to follow.


  1. I picked up a Tytera MD-380 DMR HT.  Still playing with it and working with firmware updates, but so far, I like it better than my CS-700.  I will try and get an official review shortly.
  2. Starting working on the new streaming solution, which will be based around an XPR4350 driving by a Raspberry Pi to allow the channel to be changed remotely.  I’ll also be integrating a webcam so that the remote user can see what channel the radio is on.  Step on will be to just get the radio streaming on the feed again, which I plan to work on this weekend.
  3. Going to try and utilize the DMRLinks project to make announcements over a given DMR talkgroup.  The uses for this are numerous from weather alerts to even announcements, etc.

I’m sure I’m forgetting a few things, but that’s what’s on top of my head.  I’ll get back to updating this page regularly.  As always, if you”re interested in anything I’m working on or if you have any questions or think I can help, shoot me an email.

Jul 15 2015

New DMR Repeater – Monrovia, IN

The Repeater Page has been updated to include information on my newest DMR repeater.  We’ve been working on this for a few weeks now and are happy that everything is finally complete.


Hendricks County is a bit of an RF enigma due to the terrain.  There are parts of the county, around Mooresville for instance, that are RF shadowed.  This presents a challenge for coverage except from an extremely high location.  On the analog side, the issue is remediated by remote receivers, but that isn’t an option with DMR.  We are looking at alternative locations to increase the footprint, but that process is still beginning and could take some time.


In the meantime, coverage reports are welcome.


coverage - monrovia

Jul 10 2015

NF9K Monrovia DMR Repeater Talkgroup Configuration

Time Slot 1 Talkgroups

Talkgroup Name Talkgroup ID Status PTT-On Timer Hold-off Timer Notes


3777215 Full-Time N/A 3 Open wide-area talkgroup


3181 Full-Time N/A 5 True local talkgroup

Midwest Regional

3169 PTT-Activated 15 3 Midwest US Calling Talkgroup

North America

3 FT N/A 3 North America Calling Talkgroup


9998 PTT-Activated 1 0 DMRLink's Echo Server for testing your audio

UA English 1

113 PTT-Activated 15 3 User Activated talkgroup for North America (English Only)

USA 1776

1776 Full-Time N/A 3 The Spirit of 1776!  International english-only talkgroup

Time Slot 2 Talkgroups

Talkgroup Name Talkgroup ID Status PTT-On Timer Hold-off Timer Notes

Audio Test

9999 PTT-Activated 1 0 NorCal's VU Meter (only works in Chrome) talkgroup for testing user audio


3100 Full-Time N/A 3 Wide-area inter-network tie for c-Bridges


3777216 PTT-Activated 15 3 Open wide-area talkgroup


8710 Full-time N/A 3 Crossroads DMR Statewide Talkgroup


3166 Full-Time N/A 5 True local talkgroup


310 PTT-Activated 15 4 TAC 310 is a North America English language talkgroup


311 PTT-Activated 15 3 TAC 311 is a North America English language talkgroup

UA English 2

123 PTT-Activated 15 3 UA English 2 is a North America English language talkgroup


1 PTT-Activated 15 3 Worldwide all language Calling Talkgroup

Worldwide English

13 PTT-Activated 15 3 Worldwide English Only Calling Talkgroup

Jun 03 2015

Hytera DMR Connectivity – We have lift off!

The NF9K DMR Repeater is now connected to the Hytera DMR Network!  It is a bit different that the normal approach, however DSTAR users will find some similarity in how it operates.  I’m still doing some fine tuning but here is a quick summary of how it’s currently configured.

On Time Slot 1, TG #9 is used for voice traffic.  I completed two QSO’s last night.  Audio quality was fantastic.  One of the QSO’s was another Motorola repeater and the other as a Hytera repeater.  I was not able to detect any difference in audio between the two.

The Hytera DMR Network utilizes reflectors (ala DSTAR?).  When a repeater connects they are placed on a default reflector, however a user can change that reflector from a radio by using a talkgroup to trigger the connection.  Again very similar to the URCALL field in DSTAR.  Here is what is currently running on my repeater, again all on Time Slot 1:

TG #4000 – Unlink.  This will disconnect TG #9 from whatever reflector it is currently on.

TG #4601 – Georgia Reflector

TG #4603 – Texas Reflector

You simply PTT on one of the reflector TG’s and then switch back to TG #9 for the voice traffic.  The 4000, 4601 and 4603 TG’s are only used for activation of or connection to a given reflector.  No voice traffic crosses those TG’s.

Try it out and let me know if you have any questions/issues.  The base configuration as it is will likely not change much, beyond adding some additional reflectors.  I will post updates when that happens.

The magic sauce behind this interoperability is a linux application that bridges the two dissimilar networks.

Very cool stuff.

Jun 03 2015

ARRL Technical Specialist Report – May 2015

Well, there went May…..

At the request of the users and repeater owners, a Facebook page was created for Crossroads DMR to allow for collaboration among repeater owners and users.  Facebook, as we all know, is probably the king of social media and nearly everyone uses it in some fashion.  Given its accessibility it’s an ideal platform for sharing information.

I received a comment via my website asking for some assistance in programming the Kenwood TK-981 for 33cm.  I provided some guidance on how the FCC channel numbers were used and then how to utilize the available tools to get the radio into the 33cm band.  I have a few TK-981’s and they are a solid 33cm mobile.

Officially received my repeater coordination for my DMR machine, which unfortunately resulted in a frequency change.  Now to schedule the time to reprogram the repeater and re-tune the duplexers.

Participated in a WD9BSA VE Testing session which resulted in two new Technicians and a newly minted General!

Answered some c-Bridge questions from various individuals and groups.  Some via third-party surrounding the addition of Motorola Capacity Plus radio ID’s to the database and another about c-Bridge remote control.  As is our mission, knowledge learned is knowledge to be shared.

Did a little experimentation with c-Bridge configuration and talkgroup activation.  In DMR you typically have two types of talkgroups.  Full-Time which is what is sounds like, a talkgroup that is on all the time.  The other is PTT or as some have started to call it, user-activated.  The latter requires a PTT or kerchuck on each machine to bring that talkgroup to an active status on that repeater.  PTT talkgroups are often governed by a timer, so once you activate it, it will only stay active for a set amount of time before going dormant.  Some c-Bridge admins have implemented a way to turn all PTT talkgroups on with a single PTT and likewise to turn them off.  This would give the casual listener the ability to see what’s going on an apparently idle repeater.  I’ll be working more on this as time goes on.

Successfully performed a c-Bridge inter-operability exercise with the DCI group where we liked talkgroups in a non-traditional way.  The process is called CPM or c-Bridge Peer Master.  Basically instead of using Control Center connections to link two bridges, you use a manager on each c-Bridge.  The advantage of this is that it can be used in situations where certain resources are limited and might otherwise prohibit establishing connectivity.  It was certainly a learning experience for me and I embrace any opportunity to take existing technology and apply it in a new and different way.

Worked with Mike, NO7RF, on some Parrot troubleshooting.  For those not familiar with DMR, a Parrot server is basically a simple echo audio test.  You key up the talkgroup say a few words and in a couple of seconds your audio comes back to you.  It’s a great way to see what you sound like to others.  Mike had ask if I would share the new Parrot server that I mentioned in my report last month.  I was happy to do so and once we got it setup, he wasn’t getting audio back.  I scoured my end, but was unable to turn up anything.  Ultimately the issue turned out to be a c-Bridge issue on his end.  So the Indy Parrot is squawking the great state of Washington.

As I’m experimenting with various software packages that run as linux daemons, I’ve discovered that I’d like to find a good way to tail an application logfile and have it output to a webpage.  If anyone has done something similar, I’d appreciate suggestions or information on how you accomplished the task.

Ed, K3HTK, received an email regarding Broadband HamNet which we’ve experimented with on and off.  Cory (KC9WET) seems to be off and running and has either done or is doing some of the things that Ed and I have played around with or talked about doing.  A potential new application would be to use that setup to pass IPSC traffic for linking DMR repeaters.  This could have great impact in a disaster area by allowing DMR connectivity to be established when other means may have been knocked offline by whatever disaster has taken place.  Additionally we plan to do some work with VoIP, the session initiation protocol specifically, to potentially have a PBX in a box that could also be rapidly deployed.  Certainly an interesting technology with a lot of potential.

After picking up a DMR mobile in Dayton, I began putting together what I’m going to need to interface it with a Raspberry Pi to allow for remote control of the radio.  The Raspberry Pi is uber sensitive to any voltage coming back on the GPIO interface and will fry a Pi pretty easily.  There are multiple interface boards out there that provide protection so in order to move the project forward, I’m in the process of obtaining one of them.  Luckily they run ~$15-$20.

Speaking of Dayton, Ed (K3HTK) and Eric (K9ZX) made the trek over on Friday.  By the end of the day, the dogs were barking and we were pretty toasty.  But it was a great day and while I didn’t bring home any fantastic finds, I did pickup a code generator to attach to my service monitor to generating PL, DPL, Two-Tone, etc.  It was nice to see a few familiar faces in the crowd as we made our way around.

The Naptown Amateur Group (N9AG) participated in the INQP again this year.  A modest effort on our part, but fun none-the-less.  We tested out a new logging application written by Ed (K3HTK) on various tablet platforms and made several revisions to the application throughout the day.  Ed originally wrote the app for Field Day and quickly adopted it for the INQP.  We also started looking into making some FD shirts for the club.  Since we don’t have many members, the cost isn’t the greatest, but I thought it would be neat.

At their request, I designed a new website for the Grant County ARC.  Feedback thus far is that they like the new design and hopefully through our efforts we can generate some additional interest in their club.

I received a request from the ChicagoLand DMR group for a feed of the EchoIRLP DMR talkgroup that I’ve setup.  I was happy to accommodate their request.

I think that’s pretty much it.  I spent a week in Gatlinburg on vacation the later part of the month and beyond mobile monitoring, didn’t do any hobby related activities.  I fully intended to stop by Ten-Tec and see the new facilities, but did not make it.

I’ll be travelling to Madrid, Spain in June on business.  Looking into the possibility of doing some operating there.  More on that next month!

Apr 03 2015

New DMR-MARC Talkgroups

The DMR-MARC has recently added two new talkgroups:

  • UA English 1
  • UA English 2

These are meant the be used in a similar fashion as TAC-310/TAC-311 have in the past.  They’ve opted for the term User-Activated, hence the UA in the name vs. PTT, since technically every talkgroup is PTT-activated, because you have to key up your radio, right?

As a reminder, the wide-area talkgroups such as Worldwide, Worldwide English, North America, etc. key up hundreds of repeaters and the preference is to use them as hailing channels.  Once a contact is made, you can move your QSO over to one of the UA’s and only key up those repeaters that have “activated.”

The TG’s are connected to the Crossroads DMR c-Bridge and will be live on the NF9K Repeater by the end of the weekend.


Mar 20 2015

DMRplus MBridge

I’m currently working on a project that will bridge the MotoTRBO and Hytera IPSC networks.  Up until now, those networks have been incompatible.  You can read more about the software here.  This is an exciting project as it has the potential to bring together two previously incompatible DMR networks furthering the possibilities that can be accomplished with this cool tech.

Mar 02 2015

February 2015 ARRL Technical Specialists Report

Happy snowy March to all my fellow Technical Specialists!

As I’m sure will be a big surprise to most, I continued my DMR exploits this past month.  First and foremost, my DMR repeater (441.025+, Color Code 1) was moved at it’s new home on the east side of Indianapolis.  The antenna is a 9dBi gain at 250′ and on an analog watt meter, I was pushing 25W into the feed line.  ERP was calculated at 130W.  I’m rather excited to see this machine at a higher profile and have been getting some good coverage reports from HT users around Marion and the donut counties.

Along with the DMR stuff comes my adventures into c-Bridge administration.  I’ve had to troubleshoot a few issues that ultimately were not c-Bridge related, but given that I’m still a young Jedi in the c-Bridge ways, that is where I started looking first.  It’s always nice when you can trace the problem to an external source and learn some new troubleshooting skills at the same time.

For those that are friends with me on Facebook, I posted a picture of a pile of Pick-Up-Sticks (who remembers that game?) and how it related to c-Bridge administration.  Every single change spawns multiple additional changes.  This past weekend, I was introducing Ed (K3HTK) to c-Bridge administration and the one example I gave him of adding a new talkgroup to the c-Bridge required ~30 programming changes to other super-groups just to accommodate the new TG.  That did not include the changes required just to get the new TG on the c-Bridge.  I have to say, it’s been fun, and I feel like I’m learning something new all the time, which is great!

I migrated the c-Bridge from a large server at my QTH to a hosted cloud-based server.  While the machine was quite resilient in terms of failure, I still had only a single internet connection.  Given the fact that more than just my repeater would be on it, I decided to go the hosted route.  I found a great deal for $10/month and they can spin up virtual servers in 55 seconds.  Pretty cool.  The migration process when quite well and was easier than expected.

Contacts were established with other c-Bridge partners including the NC-PRN network and MIT’s network.  While NC-PRN does not have any TG’s to share outside of their network, they have a great technical pool, so having someone to bounce ideas off of is always welcome.

I participated in a DMR Newbies Night at the IPSC building on E. 21st street on the 19th.  Due to poor weather we only had about five people not counting the host and the two presenters.  The evening sort of turned into a Meet the c-Bridge, which was a bit of a surprise to me, but I was happy to share my experiences as well as give folks a look at the mysterious inter-workings.

My membership was accepted into the North American DMR Council, which is a fledgling organization to foster communication and cooperation among the various DMR entities.  To say that there are politics in DMR is an understatement and unfortunately somewhat of a sad situation.  I’m just glad that most of it is hidden from the end users, at least at this point.

The Brownsburg Hamfest was held on February 14th.  I went out and made my rounds and did my part to support the Hamfest.  I enjoy them all, even the smaller ones for nothing else than an opportunity to get out and meet people.  Of course, the opportunity always exists to uncover a diamond in the rough on the tables.  Although this trip netted no such treasures for me.

I received quite a bit of communication from my website this past month.  Folks asking about radios that I’d worked with and taken time to write up reviews on.  I also received question looking for clarification on the various digital modes available to amateurs and how compatible they were.  Unfortunately, very few offer any interoperability, but it was nice to be able to help out a fellow Ham.  Another request was from a new DMR repeater owner who had not had luck contacting others for help.  I was able to give him some guidance and help him understand his options.  Lastly, I received a comment from someone who has been visiting my website and is now interested in getting his license.  I made some book recommendations to him and made sure that he understood that I’m available for any questions he might have and who knows, perhaps he’ll end up at one of my VE sessions!

A few emails were exchanged between other DMR authorities and I with Don West, who is the Communications Director at IDHS.  Basically they were looking to understand how DMR could function in a an emergency type setting.  We provided basic information and answered a few questions.  Not sure where that will lead, but hey, you never know.

My broadcastify feed that was originally setup for the Tuesday night DMR nets has been a hit.  A couple of times I’ve forgotten to switch it back over to North America after the net, and people have noticed.  I received a couple of emails from folks in the NE US who do not have a local DMR presence and enjoy listening to the feed.

Lastly I’ve functioned as primary net control for the Tuesday Night DMR net a few times over the month of February.  It was nice to see the numbers of people checking into the net grow each week.  Keeping people engaged in the net and keeping a round-table going has been an interesting learning experience.

Well, I think that’s it for February.  Looking forward to a break in the weather and perhaps the appearance of some spring-type weather.  While I enjoy the snow, at this point whatever else we get will be short-lived so might as well be done with it.

73 until next month!

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