EFJohnson 3000 SERIES - Manual (Page 98)

DISPATCH INTERFACE MODULE (DIM)
11-6
Figure 11-2 PTT TONE REMOTE CARD BLOCK DIAGRAM
HIGH LEVEL DETECTOR
LOW LEVEL DETECTOR
U201A/C
TO MAIN BOARD
TRANSMIT DTMF
TO MAIN BOARD
U209 U212
TONE GENERATOR
TONE LEVEL CONTROL
Q204/Q205
U214A/B
U204A/B
U208
DTMF ENCODER
U201A/C
U205 U218
U206
NOTCH FILTER
U202
U201B/D
U217C
U203
U216
2175 Hz
BANDPASS FILTER
2175 Hz
U210C/D
U211B
U211A
U210A/B
BUS
DATA
BOARD
FROM MAIN