Icom IC-820H Instruction Manual page 8

1 PANEL DESCRIPTION
Hi Accessory socket information
Input/output pin.
selectable.
Goes to ground when transmitting.
When grounded, transmits.
Modulator input. The input level is
SPECIFICATIONS
Ground level : -0.5t00.8V
input current : Less than 200 mA
Inputimpedance : 10kQor300Q
Input level : 100 or 2mVrms
packet operation.
(squelched).
Direct modulator input for 9600 bps
Main or sub band AF detector output
Regular input level: 1.0 Vp-p (0.35 V rms)
Max. inputlevel : 1.6 Vp-p (0.56 V rms)
Output impedance : 4.7kQ
Output level : 100 to 300 mV rms
Rear panel
view bps packet operation.
Direct detector output during 9600
6 SQLS Main or sub band squelch output. Squelch open
Goes to ground when squelch opens. | Squelch closed
13.8V 13.8 V output when power is ON.
ALC voltage input/output.
Fixed, regardless of [AF]
position.
: Less than 0.3 V/5 mA
: More than 6.0 V/100 nA
Output current > Max. 1A
Control voltage : ~4toO0V
Inputimpedance : More than 10kQ
Microphone up/down input.
Same as the [MIC] connector pin @ below.
* The functions of pins 4, 5, 6 and 8 are selectable via the internal switches. (pgs. 47, 48)
Hi Microphone (HM-12; optional)
Main band AF output
(varies with [AF (MAIN)])
(Front panel veiw)
@ GND
(microphone ground)
© GND (PTT ground)
@ Microphone input
@ +9V DC output
@) Frequency up/down
@ Squelch switch
[PINNO.| FUNCTION | | DESCRIPTION
Frequency down | Ground through 470 Q
Squelch open "LOW?" level
Squelch closed "HIGH" level
@) UP/DOWN SWITCHES [UP]/[DN]
Change the operating frequency or memory chan-
nel.
e Continuous pushing changes the frequency or
memory channel number continuously.
(2) PTT SWITCH (p. 25)
Push and hold to transmit; release to receive.
(@) UP/DOWN ON/OFF SWITCH [ON/OFF]
Activates and deactivates the [UP]/[DN] switch
control to prevent accidental frequency changes.
Microphone
Microphone cable
Microphone plug
Mic
element
DOWN
ates arden
; | ON/OFF
- O
Ber RECEIVE
470
o TRANSMIT
CAUTION: DO NOT short pin 2 to ground as this
can damage the internal 9 V regulator.