Icom IC-251A Instruction Manual page 31

PLL UNIT SIDE
Brake Adjustment Screw
LE! Board
Jumper Board
Q1 - Q2 (Photo Transistor TPS606)
Tuning Control Knob Shaft
1C18 (DC-DC Converter)
TONE CALL UNIT
Power Supply Unit
1C6 (NJM4558D FM Discriminator Meter -
SSB Squelch Control)
R92 (FM Discriminator Meter Full Scale Adj
DRIVER UNIT
R2 -R3 (Photo-Chopper Output
Level Adjust)
TONE CALL UNIT (IC-251E Only)
R2 (Tone Frequency Adjust)
R85 (SSB Squelch Adjust)
R80 (FM Discriminator Meter Set)
R96 (Scan Speed Control)
L13 (VCO Output Coil)
R7 (VXO 0.0KHz Adjust)
L2, L3, L4 (X1 Multiplier Coil)
VCO Unit
X1 (14.1433MHz PLL VXO Crystal)
R1 (VXO 9.9KHz Adjust)
IC2 (SN76514N PLL Mixer)
1C1 (NJM4558D Frequency Control)
L1 (X1 Oscillator Coil)
X2 (5.12MHz Reference Frequency Crystal)
IC5 (TC4081 Degit Control IC)
Power Supply Unit
PLL UNIT
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