Watkins-Johnson Company WJ-8718A/MFP Instruction Supplement page 126

WJ-8718A/MFP
Table 4-7. IF Interface Support Circuits
TABLE 4-7
Support Circuit Supports Function
U1
*
U2 *
U3 *
U4 *
U6 *
U7 *
U10A U12 Address encode
U10C NU
U10D U11 Address encode
U12 **
U13A U4*
U13B U20 Transceiver dir·ection control
U13C U2*, U17*
U13D U1*
U14A U19A Inverter
U14B
NU
U14C U25 Inverter
U14D U16 Inverter
U14E NU
U14F U10D Inverter
U15A U20
Transceiver direction control
U15B Ul1, U12 RD, WR Buffer
U16A Receiver audio
circuitry Audio squelch switch
U16B
Receiver audio
circuitry Combined audio squelch switch
U16C Receiver BFO BFO switch (used only on a standard front
circuitry panel receiver)
U17 *
U18A NU
U18B U25 RC oscillator circuit
U18C U25 RC oscillator circuit
U18D U17*
U18E
U17*
U18F U17*
U19A U20 Transceiver direction control
U19B U25
Conversion start control gate
U19D U25 Output enable control gate
NOTE: l.
NU denotes not used.
2. * Components belong to modules used only when a standard
receiver front panel is in use.
3. * * Serves to maintain integrity of the board.
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