■ Ext Keypad] Jack; ■ Ref I/O] Connector; ■ X-Verter] Connector; ■ Relay] Jack - Icom IC-7851 Instruction Manual

20
CONNECTOR INFORMATION
■ [EXT KEYPAD] jack
The circuit is used to output memory content in 8 chan-
nel memories. You can output desired memory content
such as CW Memory keyer, Voice memory, RTTY/PSK
Memory to be transmitted. Push a switch to send the
memory information. Hold down the switch for 1 sec-
ond to repeatedly send the memory information.
When you connect the external keypad, turn ON the
following items in the Others set
(SET [F-7] > OTHERS[F-5])
• External Keypad (Voice)
• External Keypad (Keyer)
• External Keypad (RTTY)
• External Keypad (PSK)
Mute switch: Mutes both transmission and reception
when the switch is turned ON.
■ [REF I/O] connector
This connector outputs or inputs a 10 MHz reference
signal.
• Input/Output impedance: 50 Ω
• Output level:
• Required input level:
• Output signal stability:
If you use an external reference signal,
set to "IN" in the "REF IN/OUT" item of the
ACC set screen.
You can adjust the internal Reference Signal frequen-
cy in the "REF Adjust" item
(SET [F-7] > ACC [F-2] > REF Adjust)
■ [X-VERTER] connector
You can connect your transverter unit
through the connector.
• Input/output impedance:
50 Ω
• Output level: Approximately –20 dBm or more
You can change the transverter function in the
verter Function" item of the
You can also adjust the offset frequency
verter Offset" item of the
(SET [F-7] > OTHERS [F-5] > Transverter Offset)
screen. (p. 15-16)
Approximately –10 dBm
Approximately –10 dBm
±0.05 ppm (0 ~ +50°C)
of the ACC set screen.
"Trans-
Others set screen.
in the "Trans-
Others set screen.
Mute switch
■ [RELAY] jack
Goes to ground when transmitting to con-
trol an external non-Icom linear amplifier.
You can select either mechanical relay or
semi-conductor MOS-FET control.
Specifications
• Mechanical relay (Reed Relay):
16 V DC/Less than 0.5 A
• MOS-FET: Less than 250 V/ Less than 250 mA
You can change the control in the "SEND Relay Type"
item of the ACC set
(SET [F-7] > ACC [F-2] > SEND Relay Type)
When the SEND terminal controls the inductive load
(such as a relay), a counter-electromotive force can
cause the transceiver's malfunction or damage. To pre-
vent this, we recommend adding a switching diode,
such as an "1SS133," on the load side of the circuit to
the counter-electromotive force.
[Example]
Switching diode
ACC 1/2
sockets
e SEND
u 15 V
20-4
L
1.5kø
± 5%
S5 S1
1.5kø
± 5%
S6 S2
2.2kø
± 5%
S7 S3
4.7kø
± 5%
S8 S4
External Keypad
screen.
To a non-Icom
linear amplifier
Relay
B
1.5kø
± 5%
1.5kø
± 5%
2.2kø
± 5%
4.7kø
± 5%
USER BOX
L
L