YouKits TJ2B, Руководство по монтажу

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GND clip to GND of DDS Unit. The reading should be 12.000.000. This is the display
fre IF (9.000.000). If there is no reading, check T1 for a cold solder joint.
The reading may be not accurate, around 12 MHz, because of the 100 MHz crystal
tolerance. If the measured frequency is not accurate, please calibrate the clock value
through SETUP.
If you don't have a frequency counter, ignore the clock calibration. You may calibrate the
clock later with the aid of beacon signal at 5 MHz, 10 MHz, or 15 MHz.
Let’s setup the DDS unit.
Press the SETUP button, IFS appears on the screen. Setup IFS later
Press again, DDS information appears.
The top line indicates the clock value. The default clock value is 100000000 (100 MHz).
Use the TUNE knob to alter the value. If the 1 Hz tuning rate is too slow, use a faster rate.
Tune while watching the frequency meter, until 12.000.000 (or 11.999.999) is measured
on the frequency meter. Press the MEM button to save this value. You can ignore this step
if you don’t have a frequency counter.
Press SETUP again, USB appears on the screen.
The default value is 3000, indicating USB and LSB are 3 kHz apart, i.e., both the LSB and
USB is 1.5 kHz from the XTL filter center frequency. Turn TUNE knob counter-clockwise to