(Last updated 2007-09-17)
I'm particularly interested in the digital area of ham radio given my extensive applications designing and programming experience. There are quite a number of interesting aspects to this ranging from long distance HF chatting to short range position reporting to bulletin board systems and email.
Digital ham radio is particularly useful for exchanging messages in an ARES situation. Voice messages are slow and error prone. It can take five to ten minutes to accurately exchange a twenty five word message via voice. Compare this to seconds even at 1200 bps.
<Insert overview of digital radio mentioning packet & BBS, APRS, Winlink 2000, digital chatting on HF and somewhat on VHF. >
You need some means of moving the tones between your computer and your radio. A Terminal Node Controller (TNC) is the older method of interfacing a serial port to the radio. Devices which attach to the computer sound card line in and line out jacks, some also with serial port or USB connectors, have become quite popular as they are considerably cheaper.
There are many software and hardware products which will do pretty much the same thing. The links below are to specific products favourably mentioned by hams both local to me and on mailing lists to which I subscribe.
"APRS was developed by Bob Bruninga, WB4APR, as a real-time local tactical communications system for rapidly exchanging digital data of immediate value to operations." APRS is mostly known as a system for using radios, GPSs and, optionally, the Internet to transmit position and weather reports as well as messages. There are quite a number of other uses for the basic concept.
One of the greatest needs at emergencies or special events is tracking equipment or people. Such as the race leader and the tail car or the Salvation Army canteen truck. These units can be permanently installed in vehicles or carried around in lunch boxes with a HT, GPS, an interface box, a battery and an external rubber duck antenna. See the NWAPRS Search and Rescue page
You can also view the APRS data either from your radio or the Internet by using software. See the NWAPRS External Links page and WE7U's APRS Client Capabilities Chart UI-View32 is one frequently mentioned APRS app. UI-Point32 is an add-in which allows you to use Microsoft MapPoint thus allowing for zoomable maps. Internet sites to view the positions of hams and objects are OpenAPRS, APRS World or Findu.com.
An excellent website with much detail is the Northwest Automatic Position Reporting System (NWAPRS) This loosely knit group is among the trend setters in the APRS world. I'd strongly urge you to join their mailing list. A good FAQ page is at http://www.nwaprs.info/faq.htm.
TinyTrak3 and the above OpenTracker are very similar products. I particularly like the TinyTrak3Plus which can also power an attached 5 VDC GPS receiver.
OpenTracker is a transmit only GPS position encoder which, when connected to a serial GPS and a radio, will transmit its location at an adjustable rate. The firmware is freely available. One ham has stated it's cheaper than the TinyTrak3 and it's quite robust.
VE6MVP's Beginners Guide To Setting Up Your Own APRS Digipeater
Winlink 2000 is now the system of choice for email and BBS. Winlink 2000 has a very robust, distributed method of handling email via the Internet. Interested hams or clubs can setup RF PMBOs to handle message traffic in their area so long as they have high speed Internet available.
One interesting feature is the ability to setup an RF link to a remote networked site and give each of the computers on that network an email address to send and receive email. Limited attachment size. <smile>
Loading WL2K User Programs aka Winlink 2000 for Dummies Assignments and mailing list for getting comfortable with Winlink 2000 without requiring a radio or TNC.
HAMS to the Rescue! Emergency communications in the wake of Hurricane Katrina came not from the government, but from a private army of amateur radio operators. Here’s how it worked.
Packet radio usage has dropped considerably with the advent of the Internet. <insert more text> WinLink 2000 has taken over much of it's role in the last few years. This section is quite short at the moment as I haven't done much research in this area yet.
The Amateur Packet Radio Handbook by Jim KA7EHK
There needs to be some method of exchanging audio between the radio and the computer. The two different methods are to hook up a TNC between the radio and a serial port or to use the computers sound card. (At least one TNC works on a USB port.)
While it may be technically possible to run wires directly between your radio and computer this is definitely not recommended due to grounding and noise issues. These devices will contain isolation transformers to assist with these problems. If you want you can extract the transformers from old modems and build these devices yourself. However I'm not quite interested in doing that.
RIGblaster is one of the well known devices for hooking up to your computers sound card. However the Rigblaster family of devices require you to change jumper cables whenever you change radios with a different mic cable or mic pin out. Thus this is more suitable for the radio in the shack.
Rascal GLX is another well known device to your computer sound card. This device has many different cables available which handle the various radios out there. This is the one I will carry with me along with cables suitable for most of the radios I own.
To use the sound card also requires that you have software such as AGW Packet Engine to encode and decode the packets. For detailed step by step instructions visit the Sound Card Packet website.
Hint: If you are in an area with a significant amount of APRS activity set your radio to the APRS frequency and see if AGWPE is receiving the packets just fine by using the Tuning Aid. I also set another radio to the APRS frequency just so I could hear get some audio feedback.
I then ran UI-View, set the Comms Setup Host Mode to AGW and was quite happy to see some APRS packets in the bottom panel of UI-View.
KPC-3+ Packet Communicator is the standard for devices between the radio and the computer however it is relatively expensive.
TNC-X is another such device and has the advantage of having the source code for the firmware available and is considerably cheaper.
USB Micro TNC family is yet another set of such devices.
Ham Radio Deluxe (HRD) is a suite of free Windows programs providing remote control for commonly used transceivers and receivers. HRD also includes mapping and PSK31 software.
MixW is a multimode program for hams. It will help you in regular and contest QSOs. You only need a soundcard to use this software and do not need a TNC.
Comments and suggestions from Ron VE6SJA, Ray VE6RHS, Curt WE7U, James VE6SRV, Bob WB4APR and David AD6ME
Website copyright 2004-2008 Tony VE6MVP