JRC JRL-2000F Service Manual page 20

(2)TUNE
When the TUNE switch is pressed, the LED of the TUNE switch lights up.
lf an exciter other than JST-135 is used, proceed to the step of "Operation of fre-
quency measurement". The state of relays is preset according to the measured fre-
quency without the steps of read-out of the
rt:~emory
and selection of the antenna:--
When the JST-135D exciter is used, the procedures described above are omitted.
Then the JRL-2000F returns to receive state and K1 of the antenna switch unit is
switched. The JRL-2000F returns again to transmit state and changes SELBK signal
to Low Ievei. The LOAD signal of the impedance detected by the impedance detector
of the CFG-111 matehing circuit is checked and the relay state is changed by one bit.
Then TUNE signal of the impedance phase is checked and the relay state is changed
again by one bit. Again the LOAD signal is checked and the relay state is changed by
one bit. The state where the LOAD and TUNEsignalsare reversed is searched for by
repeating these procedures. lf the SWR value of the impedance detector circuit is less
than 1.1, the automatic tuning is thought to be completed. During automatic tuning, the
7-segment LED is shown as in Fig.10 and the sound of when relays are switching is
heard. Also during automatic tuning, the divided Signallevel is checked at times and
"Po" is displayed when the inputpower is too small and "A6" when it is too !arge, as is
the samein the SET operation, and automatic tuning is stopped temporarily. When the
automatic tuning is completed, the data is written to EEPROM. The 7-segment LED on
the front panel is shown as in Fig.11 for an instant, and then the frequency is dis-
played. lf the automatic tuning has failed, "A7'' is displayed.
Fig.10
~
~
Fig.11
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