Digital Traffic Network

This week, my amateur radio station became an official digital traffic network (DTN) station. The main operating digital mode is PACTOR, an evolution of both AMTOR and packet radio. PACTOR uses a combination of simple phase shift keying (FSK) modulation, and the ARQ protocol for robust error detection and data throughput. PACTOR is most commonly used on frequencies between 1 MHz and 30 MHz.

I first looked into PACTOR last fall. I abandoned the idea when I learned that the terminal node controllers (TNCs) cost hundreds of dollars, an investment I was not comfortable making at the time. In December, I asked around about becoming a DTN station operator. I was told that the operational mode was PACTOR and I balked about having to obtain the necessary TNC. Then I was told that a used TNC would be provided. All I had to pay was a $15 dollar shipping charge. That was more than acceptable. Soon, the loaner TNC arrived. It was about 25 years old and supposedly could handle the required PACTOR digital node.

Advanced Electronic Applications, Inc. PK-232MBX TNC

I found a appropriate AC/DC adapter, but I had to jury-rig a mic cable to connect it to my radio and the 5 pins on the back of the TNC. I also had a audio cable on hand for the radio output to the TNC. An RS-232/serial port USB adapter cable connects the TNC to my laptop PC.

Breadboard for connecting a CAT6 twisted-pair cable to the TNC

The AirMail software was downloaded and installed on my laptop. That needed to be configured to interface with the TNC. The TNC was switched on and AirMail was opened. Following initialization of the HF mode, the TNC successfully initialized. My radio AGC was set to 6 and for 40 watts output. It was then tuned to a frequency for a nearby PACTOR station. Then the receive threshold was properly set on the TNC. I tried to connect to a PACTOR station but no joy.

After several days of troubleshooting, with the assistance of two fellow amateur radio operators, I tried a loopback test on the TNC. This involved disconnecting the TNC from the radio and connecting the mic and audio input pins, on the TNC, with a jumper wire. Then a terminal software app was setup to connect the TNC with itself. This test failed and indicated the problem was with the TNC.

I was able to obtain an identical TNC on eBay for a modest and very affordable price. When it arrived, I quickly set it up for a loopback test. The test was successful. I then connected it to my laptop and radio, and it successfully connected to a PACTOR station. The operators of two PACTOR stations modified their configurations to recognize my station. Then I was able to send and retrieve national traffic system (NTS) messages.

I now routinely log in to retrieve NTS messages from The 3rd Region Hub for The Western Pennsylvania Section, on every even numbered day, sharing the responsibility with another amateur radio operator who checks in on odd numbered days. After retrieving messages, I relay them via The Western Pennsylvania Phone Traffic Net, or deliver them via phone, email or US Mail. I also originate my own messages to send via the NTS.

Contact me if you wish to originate an NTS message.

Field Day 2020

Field Day 2020

The American Radio Relay League (ARRL) Field Day is the most popular on-the-air event held each year, on the fourth weekend in June, in The United States and Canada. More than 40000 radio amateurs gather to operate from remote locations. It is a time where many aspects of amateur radio come together to highlight its many roles. It is an excellent opportunity to demonstrate its emergency capabilities to organizations and the general public. Despite the development of modern communications systems, they can fail. When they do, amateur radio can provide communications support during emergencies and post-disaster situations.

This year was different due to the COVID-19 restrictions. Instead of gathering and setting up at public locations, amateur radio operators (hams) were encouraged to operate from home. In addition, one rule was waived to allow those operating on commercial power to contact other stations that were also operating on commercial power. All other rules applied. Some hams operated on power provided by batteries, generators, solar panels, or other means not using commercial power.

Hams across North America communicated using voice, morse code (carrier wave or CW), and many digital modes. They operated to make as many contacts as possible from 2 PM EDT on Saturday until 2 PM EDT on Sunday. According to the rules, those that waited until 2 PM Saturday to set up their stations were permitted to operate until 8 PM on Sunday.

As for myself, I made 28 contacts on the 20 and 40-meter bands using the digital phase shift keying 31 baud mode (PSK31). Each contact sent digitally is worth 2 points each. Since I used only 50 watts of power, I qualified for a multiplier of 2, so my score was 112 points. I also sent 10 formal radiograms (100 points), including one to the ARRL Western Pennsylvania Section Manager (another 100 points). Finally, I submitted my Field Day entry electronically (another 50 points). My preliminary total was 462 points. I made contacts in Alabama, Florida, Illinois, Indiana, Iowa, Maine, Massachusetts, Michigan, Minnesota, Missouri, New Jersey, New York, North Carolina, Pennsylvania, Tennessee, Wisconsin, and Ontario.

2020 Spring SET

Today was the 2020 Spring Simulated Emergency Test (SET) amateur radio network in western Pennsylvania. The SET is a training exercise involving the Amateur Radio Emergency Service (ARES) and the National Traffic System (NTS), a message-handling service of amateur radio.  Its primary purposes are to evaluate strengths and weaknesses in emergency preparedness and communications and to demonstrate amateur radio to the public.

My simulated position was at The Grays Woods Elementary School Emergency Shelter. However, I was actually operating from my home VHF/UHF and HF base stations. We were all sheltering in place due to the COVID-19 pandemic. I was mainly operating on 75 meters using the Olivia digital mode.

We were sending formal formatted messages to net control. I sent three pieces of traffic containing shelter status. However, it got a bit silly at the end of the exercise. There was a message announcing the touch down of a tornado west of Pine Grove Mills in The PSU Ag fields. Then there was a voice message concerning a hungry elephant found in a closet at Juniper Village.

More Antenna Woes

Being an amateur radio operator, I occasionally have to deal with equipment maintenance issues. I first noticed the problem when I found it difficult to communicate with several nearby VHF/UHF repeaters. Then, I noticed that my HF radio would not tune on 75 meters. I checked on all of my indoor cables and found no problems, so I ventured outside and noticed the following significant damage to my amateur radio antenna system.

Apparently, an animal had chewed through my VHF/UHF feed line. My dogs didn’t do it because it was outside of the fence.

There was also damage to the HF ladder line feed to my G5RV antenna. There were many visible tooth marks. The coax around the balun was destroyed. These components we’re well outside of the fence.

I used an auxiliary feed as a temporary fix for my VHF/UHF Yagi. I needed to obtain a new G5RV antenna.

Update: 3/4/2020
I installed a new G5RV antenna today. I also cleaned the corrosion from my feed line connectors at the balun. I was able to tune up on 75 meters.

More Antenna Woes

Today, one leg of my G5RV antenna snapped off due to the extreme cold and windy conditions. The temperature now is 9 F with a windchill of -8 F. My HF system is now out of commission until I can install a new antenna, or install the new dedicated 80-meter antenna. Sunday it will warm to the low 40s so that is the earliest I can make the attempt. Temperatures will be above freezing from Sunday until at least next Tuesday.


Right now it looks as though my NTS production for January will be a total of 41 handled messages. That is a personal monthly record.


Update: G5RV antenna was replaced.

NTS Messaging

The National Traffic System (NTS) is an organized network of amateur radio operators sponsored by the American Radio Relay League for the purpose of relaying messages throughout the U.S. and Canada.

Normally, these messages are routine greetings (“Happy birthday Aunt Mary”) to keep the NTS operators active and well practiced in the event they are needed. When there is an emergency or disaster, NTS works closely with the Amateur Radio Emergency Service (ARES) to provide emergency communications. The most common type of disaster-related messages are “health and welfare” inquiries and notifications into and out of the area affected by a disaster.

In a time of disaster, it is easy to expand the system by simply creating additional meeting times for the nets with high volume, or by setting up a specific “trunk line” between two points.

During 2018, I have sent over 200 routine messages using the phone and digital modes and during different conditions: summer heat, ice storms, rain, wind, etc. In order to be better prepared, my fellow operators and I would appreciate messages of 25 words or less. All that is needed is the message, a phone number and/or email address, plus the destination town and state. A street address is optional. You may initiate a message by sending the required information to

The Western Pennsylvania Phone and Traffic Net meets daily on 3.983 MHz LSB at 2200 UTC.

Digital Amateur Radio

There is more to amateur radio than exchanging callsigns, signal reports, and the weather. One popular segment of amateur radio is the digital modes.

Besides the high frequency (HF) radio, and a PC with a soundcard (most have them), the main piece of hardware is a sound card interface. I currently use The Rigblaster Blue (shown at the top right in the image below).


It uses Bluetooth rather than audio cables to connect to the sound card on a PC. The Rigblaster Blue has a through microphone cable so the regular microphone may be used when not using the digital modes. An audio cable is then connected between the line out of the radio to the line in on the Rigblaster Blue. The final connection is made by pairing Bluetooth on the PC to The Rigblaster Blue. Then changing the sound card settings to the Rigblaster for input and output audio. There are other sound card interfaces available such as the Signalink.

I first started with PSK31, which is a highly-efficient data mode that lets you work long distances, even when you can barely hear the signal. PSK31 stands for Phase Shift Keying 31 baud (or 31 bits per second/bps). The characters are formed by changing the phase of the sound wave, not by using different tones. Once I got my hardware setup, as well as configured one of the available software programs (I use DigiPan), I was making regular contacts with Asia and Australia.

I recently set up my station to us WinLink 2000 with the RMS Express software. As many of my friends know, I can send and receive e-mails and National Traffic System (NTS) radiogram messages over the air, rather than use The Internet.


During disasters or other emergencies, radiograms are used to communicate information critical to saving lives or property or to inquire about the health or welfare of a disaster victim. Routine messages are regularly sent to test the system and for operator practice.

Solar Wind Storm


Propagation on the 40-meter and 75-meter bands has been very poor during the past few days. I have a backlog of several radiograms to send, as a result, since it has been difficult to hear the other stations on the nets where I usually check-in.



There is a wide “hole” in The Sun’s atmosphere from which gaseous material has been flowing. The resultant solar winds have caused a geomagnetic storm to occur on Earth. The Aurora has been visible in northern Minnesota. The geomagnetic storms may last for more than a day or two.

Antenna Wear and Tear

Stormstown is nestled in Halfmoon Valley. The valley is often windy, with the flow mainly from the southwest. The winds have been taking a toll on my outdoor equipment, mainly the flags and flagpole, and my G5RV HF amateur radio antenna.

Most of the damage has been minor. In the past six months, I have had to replace the dipole wires, resolder the ladder line connectors at the feed point, replace a section of coax due to a broken connection at the feed point, and replace two clamps and three sections for the collapsible mast.

During my latest repair, to replace the coax, I secured the ladder line with cable ties. That may reduce some of the wear and tear on the cables and connections.

I am a frequent check-in on the 3rd Region Net at 2100 UTC (3.918 MHz, LSB), and The Western PA Phone Traffic Net at 2200 UTC (3.983 MHz, LSB). My callsign is WX2DX.

nts_clInformation on the National Traffic System

If you’d like to send a radiogram, send me a comment.