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2 - 1
SECTION 2
INSIDE VIEWS
•
Bottom view
•
MAIN UNIT
Top view
Digital CPU (IC20:
HD64F2239TE16
for IC-1721D/1821D
only)
PLL IC
(IC4: LMX2352TM)
APC circuit
(IC37: TA75S01F)
Mixer circuit
Base band IC
(IC2: AK2346)
D/A converter
(IC8: M62364FP)
+5V regulator
(Q31: 2SB1132)
AF amplifier
(IC38: LA4425A)
D/A converter
(IC30: M62334PP)
RX/TX VCO
circuit
IF amplifier
(Q6: 2SC4215)
Power amplifier
IC29:
S-AV32 for
IC-F1721/D,
F1821/D
S-AV33 for
IC-F1710,
F1810
DTMF decoder
(IC6: LC7382M)
FM IF IC
(IC12: TA31136FN)
RF amplifier
(Q24: 3SK293)
YGR amplifier
(Q23: 2SC3356)
Reference crystal
oscillator
(X2: CR-794 15.3 MHz)
APC circuit
VCO switch circuit
(Q17: XP1214,
Q18: DTC144EU)
Low-pass filter
(IC1: NJM129024)
A/D converter (IC16: AD7476ARTZ for IC-F1721D/IC-F1821D only)
Digital DSP
(IC41:
TMS320VC5416PGE120 for IC-F1721D/IC-F1821D only)
MAIN CPU
(IC23: HD64F2268F)
+8V regulator
(IC36: TA7808F)
T8V regulator
(Q34: 2SD1664)
Power switch
(Q42: 2SJ377)
Ceramic filter
(FI1: CFWM450E
for wide)
Ceramic filter
(FI2: CFWM450G
for narrow)