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Australian
Amateur
Packet
Radio
Association

How to get on Packet Radio

Although Packet radio involves high technology and the latest state of the art components, the basic equipment required is relatively simple to assemble (as many amateurs have found). You can of course obtain pre-assembled units at a most reasonable price.

Requirements

  • A Personal Computer and a Terminal program OR
  • A Personal Computer with TNC-emulating software such as TPK or BayCom
  • A TNC (black box) such as the PacComm Tiny-2 OR
  • A simple modem such as the BayCom modem
  • An FM transceiver

The Computer

There are of course many breeds and varieties of computer. Essentially the only requirement is that the computer be able to run a communications program. There are many such programs. paKet, YAPP, PKTWin and WINPACK can be found in public domain/shareware libraries and are also available from the AAPRA software library. The vital requirements are that its parameters can be set to:- 

        baud rate       1200 or higher
        parity          even or nil
        data bits       7 or 8
        stop bits       1 or 2
It is via this program that data is sent between you and the TNC. The commands issued to the TNC are also via the same program.

TNC and MODEM

Hardware Type
These two units are sometimes combined into a neat black box which contains its own microprocessor, usually a Z80. It will also include memory chips for holding its program and the data you will be transmitting and receiving. Another chip, the HDLC integrated circuit, does all the checking and handling of the data as it enters and leaves the TNC. The advantage of using a TNC is that your PMS (Personal Message System) is accessable even when your computer is turned off or being used for some other task.
Software Type
These modems are available in both kit and built up form and the only disadvantage is that if you want to run a PMS (Personal Message System) your machine has to be on all the time. The answer to this is use the many BBSs for leaving messages on as they do operate continuously.

Transceiver

The bulk of operation at this time is on VHF-FM. The original channel set aside for the mode was 147.575 MHz and usage has now spread to other frequencies such as 147.600, 144.800, 144.850, 144.900 & 145.050. This list is not exhaustive and specific operating frequencies depend on the area in which you are located. Typical packet action is in the lower half of the two metre band (144.700 to 145.175), so have a listen, or ask some local operators.

HF operation is increasing; this can be helpful to those living away from repeater-serviced areas. The BBS service also makes good use of frequencies within these bands. 10.147 and 14.107MHz and surrounding frequencies are popular. Gateways to 40m are also in use.

UHF usage is less popular than VHF. These frequencies are used to provide links between main centres for through traffic flow, rather than have this traffic clutter the local VHF frequencies. This is most desirable in the higher density areas.

Ideally a transceiver for Packet should have such a frequency response as to keep the levels of the Packet tones equal. PacComm have a radio tailored to the needs of digital radio only. On many BBS systems you can find radio modification files, however for 1200 baud operation the connection of your radio to the TNC is simply made by connecting to the MIC and Speaker socket and adjusting the levels to provide satisfactory performance. Full instructions will be supplied with the device you choose.

There have been: On Packet count accesses since 23/12/98
Last update to this page: 22/2/00