D74A and XLX Special Character Woes

A fellow New Jersey ham was having the hardest time using my XLX reflector. He could connect to a reflector module. He could hear conversations, but none of his transmissions were making it out over the reflector. Strangely, he had no such problems when using a DPlus reflector. His radio is a Kenwood D74A.

He uses a SharkRF openSpot2 as his hotspot. While helping to search for a solution, I remembered a thread I saw on the Pi-Star Forums. The author complained of not being heard on an XLX reflector via a D74A. The cause and the solution had nothing to do with Pi-Star, but rather it proved to be a quirk with the D74A and the XLX software.

Apparently the D74A allows any character to be entered into the Callsign Extension field. These are the 4 bytes following the “/”. While these characters were orignally made available to support reciprocal operations and portable suffixes, they are now commonly used to identify the type of radio being used. So my D74A callsign is setup as K2IE____/D74A (the underscores represent spaces). My friend’s radio had “@?” in the Callsign Extension field. These unexpcted characters seemed to cause the XLX reflector to ignore the attempted transmission.

The Icom radios support only A-Z and 0-9 in the callsign extension field. The D74A allows lowercase and special symbols too. Don’t use anything other than A-Z and 0-9 in the Callsign and the Callsign Extension fields and you won’t have this problem.

To make things more interesting, the ham who reported this issue is visually impaired. He relies upon the radio’s voice prompts. However, the Kenwood D74A voice prompting system ignored the @? characters completely, so he never had any idea that they were present. Another local ham who was alerted to the special character problem on the D74A spotted the issue and fixed things.

73 de K2IE

D-Star & DMR Interoperability

If you’re a fan of either D-Star or DMR, you have probably noticed the proliferation of multi-protocol gateways. These gateways, such as the XLX020 system, permit users of radios of one type to communication with users of radios of another type. Multiprotocol gateways help to defragement the amateur digital landscape.

However, there can be issues if the transmitting operator is not registered on both systems. Have you been on a DMR radio and seen the transmitting party display as radio id 0? They are a D-Star (or Fusion or P25 or NXDN) operator who has not registered a DMR radio number.

For DMR operators who have not registered with their nearest D-Star gateway, transmissions could even fail to pass through the D-Star gateway to connected D-Star repeaters.

Therefore, k2ie.net highly recommends that all amateurs using any digtial voice mode register for BOTH a DMR radio id and with a local D-Star gateway, whether or not you have a corresponding digital radio.

You can register for a DMR radio ID at http://www.radioid.net. Hams in Europe and Africa should register at http://www.ham-digital.org.

If you’re not sure of your local D-Star gateway, you can follow the instructions at https://www.dstargateway.org/D-Star_Registration.html.

73 de K2IE

K2DLS is now K2IE

My callsign has changed and we are migrating the blog over to http://k2ie.net. Please update all bookmarks that formerly pointed to k2dls.net.

I’ve been asked, “Why did you change your callsign?”

1×2 callsigns are hard to come by, especially one from your own call area. K2IE is an especially easy call for CW use. And, I was a friend and co-worker of the former holder of this callsign, Robert Norton. Unfortunately, Bob became a silent key well before his time.

Bob and I used to talk about radio and he encouraged me to get my amateur radio license. He also provided some insight into the hobby that I draw upon to this day. It is an honor to hold his callsign.

73 de K2IE