ozQRP DDS VFO 2, Руководство по монтажу

Страница: 22 / 24

DDS VFO 2 Construction Manual – Issue 1 Page 22
9 O
PERATION
9.1 P
OWER ON
When the DDS VFO is powered on the version number is displayed briefly. This is followed by
the operating display shown in Figure 7. Note that RIT is only displayed when RIT is enabled.
Figure 7 LCD operating display
9.2 T
UNING
To tune the DDS VFO rotate the encoder clockwise to raise the frequency and counter-clockwise
to lower the frequency. The frequency will change by an amount equal to the Step value.
9.3 F
REQUENCY STEPS
To change the current frequency step press the encoder push button for less than 1 second and
release. Each press cycles through the available steps which are 10KHz, 1KHz, 100HZ and 10Hz.
9.4 RIT
In receive mode press the button down for longer than 1 second. RIT will be displayed on the
bottom line. The frequency can now be adjusted independent of the transmit frequency.
When switching to transmit mode the DDS will revert to the transmit frequency.
To exit RIT, press the encoder push button for longer than 1 second. The RIT message will
disappear and the receive frequency will equal the transmit frequency.
9.5 V
OLTAGE
D
ISPLAY
The power supply voltage is displayed in the lower right hand side of the LCD. This is updated
every 500mS. If the voltage falls below 8V a low voltage warning message is displayed to
indicate the power supply is too low for proper operation.
7.100.000 L RX
1kHz RIT 13.8V
Frequency
Power Supply
Voltage
Frequency
Step
USB/LS
B RX/TX
RIT