S-meter and Battery voltage
An S-meter and battery voltage indicator can be enabled for display on the LCD. These are both
configurable to your needs. The battery voltage indicator would be useful if you intend to operate
the radio portable on battery power.
Real time clock
A real-time clock can be displayed at the bottom right of the LCD. The time can be set by
connecting a GPS receiver such as the QRP Labs QLG1 temporarily to the QCX. When power is
disconnected from the QCX, the time is lost and will start at 00:00 at next power-up.
Built-in alignment tools
One of the nicest features of this CW transceiver kit, is the built-in alignment tools menu. The radio
can act as its own signal generator, injecting an appropriate signal into the receiver front end, then
measuring the audio amplitude after single-sideband demodulation. The menu items allow you to
easily peak the Band Pass Filter adjustment, and to adjust the I-Q balance and audio phase shift
adjustments for best unwanted sideband cancellation.
Built-in test equipment
For those times when the assembly didn’t quite go as well as we hoped, and we need to do some
debugging – the radio includes its own suite of test equipment too! None of these items of test
equipment are going to replace a $100,000 lab any time soon – but they provide very useful
measurements for helping people without much test equipment, to debug the radio. They can even
be used for testing other projects too!
Voltage meter
RF Power meter
Audio channel amplitude measurements
Frequency counter (0 to 8MHz)
Signal generator (3.5kHz to 200MHz)
CAT control - PC Control commands
The QCX kit also supports CAT control commands by a 38400 baud serial data interface (TTL
voltage levels). This implements a subset of the Kenwood TS-480 command set, with one or two
minor exceptions.
It is intended to allow easy operation of the QCX in conjunction with logging software, which
typically queries the transceiver to determine operating frequency and other operating parameters.
The CAT control interface also supports some basic control features for remote control of QCX if
required.
GPS Interface
The QCX kit has a GPS interface, which is used for calibration, setting the real time clock, and for
frequency and time discipline and locator setting during WSPR operation. The GPS interface
(1pps and 9600 baud serial data) shares the same pins as the paddle dit and dah signals
(necessary due to limited processor I/O).
The GPS should ONLY be connected during oscillator calibration menus 8.11 and 8.12, or
when the beacon is enabled (menu 6.1 is ON). Connection at other times puts the radio into
practice mode (no RF emitted) to protect the PA, and may also corrupt menu entries. You
may temporarily connect the GPS while in ordinary operation mode, for the purposes of
setting the real time clock.
QCX operating manual, firmware 1.07, manual edit 0.03
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