The intelligence of the Packet Radio system is handled with a hardware or software approach. The software approach uses your computer’s existing hardware (sound card and a separate interface) with corresponding software to decode the data. The hardware approach is provided with a TNC (or Terminal Node Controller). The Mutimode Controller is basically a TNC designed to decode additional modes. While I recommend the use of a TNC, it’s really up to you and your configuration skills.
AGWPE is a free software program that can be used with its addition packet module to allow your computers sound card to encode and decode the data. This setup would then replace a hardware TNC. Some have had great luck with it. I have not. I still plan to play around with it sometime but I have had much better luck with hardware TNC’s. You can download and get additional information about AGWPE by clicking here. (NOTE: I have used AGWPE quite a bit and really like it. I think is great for laptop use. It can be a bit tricky to setup but I find it works quite well. 73, KCØNCQ) If you don’t currently own a TNC and but you do own, or can built a sound card to radio interface, I would suggest you try the AGWPE. In most cases, the same interface use for HF PSK31 will also work for VHF Packet
If you don’t own a sound card interface you should be able to find a used TNC for about the same money as a new sound card interface. Remember that there are a lot of used TNC’s sitting in closets collecting dust. I have purchased an MFJ for $55, a Kam for $50, a KPC 3 for $40 and a KPC 3+ for $110. And if it makes a difference, get a Kantronics product. I say this because most of the packet users around here use Kantronics. The other brands work fine but you will probably be able to get a little more local support if you stick with Kantronics. (Click here to check out what is currently on EBAY!)
If money is not a big factor consider the Kantronics KPC 3+ for about $200. Remember however that it is VHF only. For about $400 you can get a new Kam XL with will do VHF and HF Packet as will as RTTY, Pactor and a few other modes.
And if you feel real spendy, you can get the Mercedes of TNC’s and go with the SCS brand that runs from the mid $800’s to about $1200.
Back to reality, most users do not need the latest and greatest. Any used TNC is good repair should do you fine. And if you have a radio with in internal TNC use it. I have been using the Tasco TNC included in the D700 and TS 2000 for about a year now. It is not as feature rich a an external unit but it gets the job done in most cases. The Alinco DR 135 can be modified with a Tasco TNC. If you have the 135 with the Tasco chip in it us it. If your thinking about buying it new, I would suggest you go with the KPC+ instead.
For additional information about the exciting digital modes, you may want to look at the ARRL Amateur’s Radio Handbook.
