Category : Science and Education
Archive   : ICOMSCHM.ZIP
Filename : IOSCH.TXT

************ Acquired from CompuServe HAMNET Forum: *****************


COMPUTER INTERFACE CIRCUIT FOR CAT CONTROL (IBM GROUP)

+9v to +12v (9v battery OK)
+| | - Add DPST switch at X's
TO IBM/COMPATIBLE ----------------O -X-||||--
| | | | | _|_ TO RADIO
| < /// (Numbers shown are
232 CONNECTOR | <10 k for 6 pin din conn.
| | < for FT-980 only)
| |
1<----o--------------------------------------------o---------->(1) GND
7<----| | | |
| | | |
| |/|2 100 k | |
4/+|-----/\/\----|------------------------->(2) TTL
| / | | | SIGS
3.3 k 1 / | | | | FROM
3<------/\/\-----/ U1A| | | RADIO
\ | | | |
| \ | | |\ | |
\ |3 | | \| | |
| \-|-----/\/\----o------| /|----o
\| 100 k |/ | | |
| 1N914 |
-----\/\/------- (Radio Shack | |
| | 100 k | 276-1122) |
| |\ | | |
2<------/\/\--o--|-\ | |
18 k 6| \ | | /| | |
| | \ 7 | |/ | |
|U1B \------o----/\/\------|\ |----------o--->(3) TTL
| / 47 | \| | | SIGS
2 | /11 1N914 | | TO
| /| | | RADIO
-----|+/ | U1 LM324 Quad Op Amp | |
| 5|/ | (Radio Shack 276-1711) | ------
| | | /\1N914
| | Build circuit on bread- | / \
> | board(Radio Shk 276-175) | ----
> 100 k | | |
> | - | | + | |
| O --X---------||||---| | |
_|_ -9v to -12v | | _|_ _|_ _|_
/// (9v battery OK) /// /// ///

For use with any interface activity. Schematic in Public Domain.
(For an FT-980 radio CAT control program download CAT980 or send
$5.00 for disk. Specify disk size.)

K5YEF/Art Harding/PO Box 861719/Plano, Tx. 75074/USA