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3-7-38 EXPANDER IC (DISPLAY BOARD; IC4)
1 KI0
Input por t for [CLEAR], [DUAL
WATCH] and [SPLIT].
2 KI2
Input port for both main and sub
bands [APF/TPF].
4
KI3
Input port for both main and sub
bands [FILTER] and [PBT CLEAR].
5
KI1
Input port for both main and sub
bands [NOTCH], [RIT] and [
Δ
TX].
12 PITL
Input port for [CW PITCH] control
signal.
13 MNCL
Input port for [NOTCH] control for
main band signal.
14 SDGL
Input port for [DIGI-SEL] control for
sub band signal.
15 SNCL
Input port for [NOTCH] control for sub
band signal.
Pin
Port
Description
number
name
3-7-39 EXPANDER IC (DISPLAY BOARD; IC5)
1 KI8
Input port for [ ] switches from first to
fourth.
2 KI10
Input port for [AGC VR], [NR] and [NB]
switches for main band.
4 KI11
Input port for [MONI], [TUNER] and
[TIMER].
5 KI9
Input port for [AGC VR], [NR] and [NB]
switches for sub band.
12 KI7
Input port for [ ] switches from fifth to
seventh.
13 KI4
Input port for [7 (3)], [18 (6)], [28 (9)]
and [F-INP (ENT)].
14 KI5
Input port for [3.5 (2)], [14 (5)],
[24 (8)] and [50 (0)].
15 KI6
Input port for [1.8 (1)], [10 (4)], [21 (7)]
and [GENE (.)].
Pin
Port
Description
number
name