Amateur Radio
Packet Interface for the Yaesu FT-817
Disclaimer:
You use the information on this page ENTIRELY AT YOUR OWN RISK. I (the author of this page) will NOT
be held responsible for anything that happens as a result of using this information.
Introduction:
In order to transmit packet data from the FT-817, the radio's PTT (Push
To Talk) must be activated. AGWPE uses the RTS (Request To Send) pin on
the serial port to signal this. A simple circuit can be used to achieve
this, and is described in the following text.
Note that although this interface is intended for the Yaesu FT-817, it
should be fairly easy to adapt it for other rigs with separate Transmit,
Receive, PTT (Push To Talk) and Ground connections. The connector
between the interface and the rig is all that will need to be changed.
See your rig's instruction manual for connector details.
Some smaller handheld rigs (for example) do not have PTT connections.
This interface will NOT work for these.
Required Components:
2 x 3.5mm Mono Plug
1 x 9 Way D-Type Socket
1 x CT-39A Packet Interface Cable (see note 1)
1 x 10k Resistor
1 x 2N3904 Transistor (see note 2)
Cable to connect 2 pins of D-Type socket to main circuit
Stripboard
Note 1:
This cable is sold by companies such as
Waters and Stanton specifically for this purpose. Alternatively,
many computer mice connect to the PC using a connector that fits in to
the FT-817 data connecter. If you have any old mice with such a connector
then it's lead could be used. Pinouts for the FT-817 data connector are
shown in the FT-817 operating manual (page 41 in mine).
If you do use the CT-39A cable, the wires are colored as follows:
| Brown |
1 |
Data Input (Tx Audio) |
| Red |
2 |
Data Ground |
| Orange |
3 |
PTT (Push To Talk) |
| Yellow |
4 |
Rx Data (9600 Hz) |
| Green |
5 |
Rx Data (1200 Hz) |
| Blue |
6 |
Squelch Status |
Not all of the connectors on this will always be required. For APRS work
(using UI-View) for example, only
the Data Input, Data Ground, PTT and 1200 Hz Rx
Data connections are necessary.
Note 2:
Pinouts for the 2N3904 Transistor, are as follows:
Circuit
Now What?
In order to use this interface, the AGW Packet Engine (AGWPE) needs to
be installed and set up. I won't describe how to do this here, as there
is an excellent guide already available
here. There
are also links to the software from that page.
Once AGWPE has been started, the appropriate packet software (e.g.
UI-View or
WinPack)
can be executed.
I'll look forward to seeing you on UI-View (144.800 MHz)...
