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Adjustment
of PLL synthesizing oscillator (2)


Tools which are necessary to adjust


Procedure of the adjustment
    The adjustment preparation
      When using the IC sockets, remove the ICs(IC1 to IC2) from the sockets.
      (Because the IC breaks when there is a mistake in the wiring, it is for the safety).
      Confirm sufficiently about whether there is not a solder-bridge (contacting the terminal or the wiring in the neighborhood with solder) because the wiring is small.
      As for the parts such as the capacitors, the diodes, the transistors which have the polarity, confirm whether or not the mounting is right.



    The confirmation of the power supply voltage
      Connect the power supply.
      Make the circuit tester the voltage measurement mode and connect the negative lead line with the grounding and measure the following voltages with the positive lead line. In all voltage measurement after this, the negative reed connects with the grounding.
      When the +5 V line voltage isn't over, because to short-circuit is thought of, switch off the power supply at once.

        The +5 V power supply voltage
        The 3rd pin of IC1
        The 8th pin of IC2

      If the confirmation of the voltage ends, removes the power supply once and mount the ICs(IC1 to IC2).
      Don't attache or remove the ICs as it turned on the power.The ICs have broken.
      If mount of the ICs ends, turn on the power again.



    The confirmation of the reference frequency
      Connect the frequency counter with 25th pin of MC145163 and confirm the reference frequency.
      It is OK if 10.24 MHz are over as the reference frequency.

      When not working normally
      When 10.24 MHz aren't output, the crystal oscillation circuit must be confirmed.

        The crystal oscillation circuit
        Confirm solder-bridge, solder-loose (solder isn't stuck right) by the watching because the crystal oscillation circuit is only the wiring.



    The setting of the dividing ratio
      Specify with the BCD in the dividing. The output of the counter can be used if there is a BCD counter which was introduced by "the digital dial".
      When the BCD input opens, it is the same as the L condition.
Dividing ratio102101100 Output frequency
(MHz)
202322212023222120
1400LLLLLLLLL133.300
1401LLLLLLLLH133.310
1402LLLLLLLHL133.320
1403LLLLLLLHH133.330
1404LLLLLLHLL133.340
1405LLLLLLHLH133.350
1406LLLLLLHHL133.360
1407LLLLLLHHH133.370
1408LLLLLHLLL133.380
1409LLLLLHLLH133.390
1410LLLLHLLLL133.400
1411LLLLHLLLH133.410

Omission
1595HHHHHHLHH135.250
1596HHHHHHHLL135.260
1597HHHHHHHLH135.270
1598HHHHHHHHL135.280
1599HHHHHHHHH135.290

"L" shows 0 V and "H" shows +5 V.


    The confirmation of the output frequency
      Make all terminals of the dividing ratio specification the open (L) condition.
      Connect the frequency counter with OUT1 and confirm that the 133.300-MHz frequency is over to OUT1.
      When the normal output doesn't come out, it adjusts L1.
      Connect +5 V with the dividing ratio input terminal in order which is shown below and confirm that the frequency changes.
Terminal name Output frequency
(MHz)
100-20133.310
100-21133.320
100-22133.340
100-23133.380
101-20133.400
101-21133.500
101-22133.700
101-23134.100
102-20134.300




    The adjustment of the output buffer
      Adjust the resonant frequency of the output buffer with the simple-type high frequency detector.
      Adjust for the output voltage to become the highest.
      In case of OUT1, adjust L2 and in case of OUT2, adjust L3 respectively.

    The adjustment ended above.