Appendix; Packet Radio Operation - Yaesu FT-8500/mh-39 Manual

APPENDIX
Packet Radio Operation
The FT-8500 provides a convenient rear-panel DATA
jack for easy TNC interconnections. Aefer to the
graphic tor pin-out connections.
When the DATA jack PKS line is grounded, data
transmission is enabled and the microphone circuit
is
disabled during transmit. However, keying the MH-39
PTT at the same time defeats this and a "live mic" will
occur, so be careful. Band selection and data rate
(1200/9600 BPS) can be selected via the program-
ming menu on page 72.
Note: Tx and Ax audio via the DATA jack is deter-
mined by menu programming
f~40:
DHTH .JHCK
SELECT),
even if the main channel indicated by
fmll)
is the other band.
To use the FT-8500 for packet, first select the desired
band and data rate for operation. Construct or pur-
chase a patch cable for connection between the
FT-8500 and your TNC and refer to the table at the
right for complete level and switching information. If
your TNC uses a PLL-type DCD (Data Carrier De-
tect) circuit, you may not require the squelch status
input from pin 6 (SaC).
DATA JACK PIN CONNECTIONS
I'
PIN
I
LABEL
I
NOTES
i
Packet Data Input
1 PKD
Impedance: 10 kn
Max. Input Level: 40 mVpp
@
1200 bps
2.0 Vpp
@
9600 bps
2 GND
i
Signal Ground
i
I
Packet Send: PIT switching:
i
3
,
PKS
I ground to transmit-MH-39 mic
circutt:
i I
disabled durmq data transmission.
I
RX9600
i
9600 bps Packet Data Output:
4
Impedance: 10 kn
I :
Max. Output: 500 mVpp
@
9600 bps
1200 bps Packet Data Output:
5 RX1200
Impedance: 10 kO
I
Max. Output: 300 mVpp
@
1200 bps
Squelch Control
I
I
I
6
i
sac
Squelch Open: +5V (TIL)
I:
I
II
I
Squelch Closed: OV (TIL)
SQC.~~
RX
CEil CEil
9600
~ 0
§
PKS
L!;DL!;D
GND PKD
(as viewed from the rear panel)
51