Ohio Section Journal – The Technical Coordinator – June 2020 edition

One of the responsibilities of the Technical Coordinator in the Ohio Section is to submit something for the Section Journal. The Section Journal covers Amateur Radio related things happening in and around the ARRL Ohio Section. It is published by the Section Manager Scott – N8SY and articles are submitted by cabinet members.

Once my article is published in the Journal, I will also make it available on my site with a link to the published edition.

You can receive the Journal and other Ohio Section news by joining the mailing list Scott has setup. You do not need to be a member of the ARRL, Ohio Section, or even a ham to join the mailing list. Please sign up!

If you are an ARRL member and reside in the Ohio Section, update your mailing preferences to receive Ohio Section news in your inbox. Those residing outside the section will need to use the mailing list link above.
Updating your ARRL profile will deliver news from the section where you reside (if the leadership chooses to use this method).
Go to www.arrl.org and logon.
Click Edit your Profile.
You will be taken to the Edit Your Profile page. On the first tab Edit Info, verify your Email address is correct.
Click the Edit Email Subscriptions tab.
Check the News and information from your Division Director and Section Manager box.
Click Save.

Now without further ado…


Read the full edition at:

THE TECHNICAL COORDINATOR
Jeff Kopcak – TC
k8jtk@arrl.net

DSCF5081 K8JTKHey gang,

As Technical Coordinator for the Ohio Section, I oversee the section’s group of Technical Specialists. The Specialists and I are here to promote technical advances and the experimentation side of the hobby. We encourage amateurs in the section to share their technical achievements with others in QST, at club meetings, in club newsletters, hamfests, and conventions. We’re available to assist program committees in finding or providing suitable programs for local club meetings, ARRL hamfests, and conventions in the section. When called upon, serve as advisors in issues of RFI and work with ARRL officials and appointees for technical advice.

The Technical Specialists really make all this happen. In the Ohio Section, there are about 15 qualified and competent Specialists willing to help. They meet the obligation of advancing the radio art bestowed to us by the FCC. The TSes support the section in two main areas of responsibility: Radio Frequency Interference and technical information. EMI/RFI includes harmful interference that seriously degrades, obstructs, or repeatedly interrupts a radio communication service such as ham radio or public service agencies. RFI sources range from bad power insulators, industrial control systems, other transmitters or poorly made transmitters, personal devices like computers, monitors, printers, game consoles, to grow lights and poorly made transformers – including one’s hams brag about getting from China for a few dollars. I die a little inside when I hear this. Our Technical Specialists can help track down interference or locate bozo stations. Technical information is a wide-ranging category including everything from antennas to Zumspots.

How can we help? The knowledge and abilities of YOUR Technical Specialists are really quite impressive. Here are some examples:

  • Antennas (fixed, portable, and emergency operation type) and feedlines
  • Antenna systems such as towers, guying, coax, and baluns
  • RF and tower safety
  • Grounding
  • Propagation
  • Electronics and circuits
  • Tube technology, aka boat anchors
  • Digital modes – including D-STAR, DMR, Fusion, P25, APRS, IGates, packet, MT63, FT8/4, Olivia, PSK, and using programs like Fldigi
  • NBEMS – Narrow Band Emergency Messaging System
  • Computers, Windows and Linux, Raspberry Pi
  • Embedded devices
  • Networking: IP networks, AMPRNet, routers, firewalls, security, mesh, and microwave
  • Repeater controllers and high-profile systems
  • Internet and VoIP linking systems – Echolink, AllStar, HamVoIP, DVSwitch, and PBX/Asterisk
  • RFI detection from power lines and consumer devices including working with governmental agencies to track down interference
  • Professional certifications such as Motorola Certified Technicians, Certified Journeyman Electronics Technician, General Radiotelephone Operator License (GROL), and Society of Broadcast Engineers (SBE) affiliations

This impressive list of qualifications is an available resource to all in the Ohio Section. Looking for help in one or more of these areas? Need a program for your club? How about a technical talk or forum at your hamfest? Assistance or direction on a project? Feel free to contact myself. My contact info is near my picture and on the arrl-ohio.org website. I’ll assist getting you in touch with an appropriate Technical Specialist. One of the Specialists might hear a plea for help and reach out to you as well.

Over the last month, we gained 3 new Technical Specialists! I would like to welcome Nick – N1TVI who is a Certified Journeyman Electronics Technician and brings experience in commercial radio systems. He is Trustee for the Northern Ohio Digital (N8NOD) repeaters in the northern Ohio area. Other experience includes repeater systems, power, grounding, and antenna systems. Jason – N8EI brings us his experience in repeater building and maintenance for the W8WKY machines in Doylestown and others, supports SHARES organizations, voice and data digital modes, and IP technology. Last, but not least, John – N8CD is co-builder of many multimode repeaters and an AllStar linked repeater system. Both John and Jason maintain a resilient network of 5.8 GHz microwave and Internet links that connect repeaters they and others maintain. They put a lot of work into their network implementation and use AMPRNet (network 44) IP addresses. Welcome to our newest Technical Specialists! Contact them or myself should any of those topics be of interest to your club or hamfest.

Pi-Star Update

Pi-Star 4.0 was released in beta earlier this year and 4.1 available as general release since most of us have been working from home, March 2020. According to the change log, these later versions bring many improvements for cross-mode support. These are YSF2xxx and DMR2xxx options: YSF2NXDN, YSF2P25, YSF2DMR, DMR2NXDN, DMR2YSF. There is no direct way to upgrade from 3.4.x or previous to 4.1.x. You must reflash your existing installation card or flash a new SD card. A new card is preferable in case you have a problem with the new version, pop-in the old SD card and boot. If your hotspot is a Pi-Zero, you should not overwrite your existing install right-away and give the new version a try on a separate card first.

Pi Zero W with ZUMSpot GPIO HAT board, compared to a quarter

Perform a backup in the web interface on the existing device. On the Dashboard, click Configuration, login, then click “Backup/Restore.” This will download a ZIP file with Pi-Star settings to your PC. Boot the new SD card and perform a restore by uploading the same ZIP file. I noticed some settings previously set were defaulted to initial values in the web interface. Do a once over for important settings and re-set them as necessary.

Pi-Star runs on nearly all Raspberry Pi models with a supported digital modem. It solved a problem, 3-4 years ago, when everyone making their own Raspberry Pi digital interface board with their own operating system image. It was anyone’s guess as to which worked and which was the “best” option. None of them worked well or consistently between users. Pi-Star solved that problem by taking the MMDVM software that can “speak” many different digital modes and network types, implemented a web front-end, and supported nearly all digital hardware boards. Once I got the hang of Pi-Star, I became a fan. The site by KE0FHS is probably the most complete documentation “notes” of the Pi-Star in one place. It’s a good read and provides a lot of great information about Pi-Star. I came across it looking up how to do custom host files for private reflectors.

One thing Andy – MW0MWZ, who wrote the Pi-Star web configuration front end, pointed out on the website was the move to Raspbian Buster for version 4.1 has been “painful” – citing missing drivers in releases among other issues. My experience with Pi-Star 4.1 on a Raspberry Pi Zero W was also painful. I’ll preface this by saying I tried 4.1 on a Raspberry Pi 3B and had less problems. I have a ZumSpot GPIO HAT for the Raspberry Pi. On the Pi Zero, after booting the first time, I was frequently greeted with weird errors and timeouts trying to configure the hotspot. Some settings were not remaining after I “applied changes.” Selecting my ZumSpot HAT from the modem list and saving, I would get a subsequent message saying I needed to select my modem from the list. Doing this a handful of times it would finally save. I saw ‘gateway timeout’ messages on both the Pi Zero W and Pi 3 during the first configuration session. I was able to seemingly avoid the timeout and configuration issues if I booted the Pi-Star on the new SD card and didn’t touch or connect for 15 minutes. Plug-it in and walk away for 15 minutes.

Pi-Star dashboard (v3.4)

Once I figured that out, configuration went smoother. The web interface, though, sluggish is a nice way to put it. On the Pi Zero W with a fully updated Pi-Star 4.1.2 install, making any changes on the configuration page would take (on average) 1:45 to save. That’s right, one minute and 45 seconds. This is unusable. I’m changing modes constantly. Think about a net you forgot about. If you have to turn off one mode and turn on another, that’s 1:45 right there. Needing to make further changes to the newly enabled mode (change previously used reflector or network), you’re looking at 5 minutes before you’re on the net – if you don’t screw up. Some nets are over in that time. In comparison: 3.4.17 is at a somewhat more tolerable 45 seconds to save using a Pi Zero. Running both versions on a Pi 3B was nearly identical at about 25 seconds after clicking apply.

CPU load was much higher using 4.1.2 on the Zero. I suspect the under-powered nature of the Pi-Zero, OS and kernel upgrades in addition to the updated code of MMDVM and associated modules is causing these delays. As popular as the Pi Zero form factor is for addon boards and portability, it’s just waaaaaaay to slow for me to be useful. Not making configuration changes in the dashboard you won’t notice these issues so much because it runs fine otherwise. Stick with 3.4.17 on a Pi Zero or consider moving to a faster Pi like the 3B if you need 4.1.2 features now.

K8JTK Hub – now with P25 & NXDN

A quick update on my interlink system pet project, K8JTK Hub, I was able to add two more modes: NXDN and P25. Both are TG 31983 using hotspots or repeaters running the MMDVM software. If I include Wires-X (because it’s not full-time), that’s 6 digital systems and 3 analog systems – a total of 9 – that can communicate with cross mode interoperability. Being part of the AmateurLogic.TV net on Tuesday evenings, I determined packet loss was causing frequent data drops and disruptions. I moved the system to a new provider and that has remedied the problem. The net right after saw a significant improvement in data stream reliability. Huge thanks to the AmateurLogic guys allowing their net to be a load test of the system. They have a lot of fun with it as participants check into the net multiple times testing different modes. The Hub is open for all to use and for testing setups, all the ways to get connected are available here.

Field Day Bonus Points

Field Day will likely be completed by the time you read this, keep this in mind for next year. Sending 10 messages over RF from your site gets you 100 bonus points – including Winlink messages. I love to receive messages about your setup, stations, operating, or social activities taking place. These can be sent via the National Traffic System (NTS) or Winlink – K8JTK at Winlink.org – to my station. The Field Day rules state messages must leave via RF from the site (7.3.6). It does not state “formal messages” be in any particular format or utilize any particular network. A message to the SM or SEC must be in radiogram format and leave via RF or no credit will be given (7.3.5). If there is any question or problems, send the message using the NTS network or Radiogram form in Winlink.

With July around the corner, if you’re looking to do something while flipping burgers at your 4th of July picnic, my favorite event is the 13 Colonies Special Event which will be on the air July 1 – 7.

Thanks for reading and 73… de Jeff – K8JTK