QRP Labs QCX User manual

QCX Transceivers
QCX/QCX+/QCX-mini 5W CW Transceiver kit
OPERATING INSTRUCTIONS
irmware version 1.07
This is the Operating Instructions manual for the QCX, QCX+ and QCX-mini CW transceivers.
All versions of the firm are are compatible ith all PCB revisions and all models of the QCX
family. Ho ever there are features hich are specific to certain models.
1) CAT control can only be used on the QCX+, QCX-mini, and the more recent PCB revisions of
the QCX (unless you have modified your older QCX to add the three components that facilitate the
CAT port).
2) Control of the LCD module LED backlight is only applicable to the QCX-mini and these settings
have no effect in the QCX and QCX+ models.
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Table of Contents
1. Overview of features..................................................................................................................................................3
2. isplay elements........................................................................................................................................................5
3. Operator Controls.......................................................................................................................................................6
3.1 Tune rate...............................................................................................................................................................6
3.2 Keyer speed...........................................................................................................................................................7
3.3 RIT..........................................................................................................................................................................7
3.4 VFO mode..............................................................................................................................................................8
3.5 VFO A/B operaons...............................................................................................................................................8
3.6 Frequency Presets.................................................................................................................................................8
3.7 Automated message transmission mode..............................................................................................................9
4. Menu System............................................................................................................................................................ 10
4.1 Saving current operang parameters (VFO frequency etc).................................................................................10
4.2 Types of conguraon menu item.......................................................................................................................11
4.3 Eding a conguraon menu parameter.............................................................................................................11
4.4 Eding a LIST parameter......................................................................................................................................12
4.5 Eding a BOOLEAN parameter............................................................................................................................12
4.6 Eding a NUMBER parameter..............................................................................................................................12
4.7 Eding a TEXT parameter....................................................................................................................................13
4.8 Frequency presets menu.....................................................................................................................................14
4.9 Messages menu...................................................................................................................................................14
4.10 VFO menu..........................................................................................................................................................15
4.11 Keyer menu.......................................................................................................................................................17
4.12 ecoder menu...................................................................................................................................................21
4.13 Beacon menu.....................................................................................................................................................23
4.14 Other menu.......................................................................................................................................................30
4.15 Alignment menu................................................................................................................................................34
4.16 Test equipment.................................................................................................................................................38
4.17 CAT Control commands (PC remote operaon)................................................................................................41
5. Operaon reference “cheat sheet”...........................................................................................................................51
6. Resources..................................................................................................................................................................52
7. ocument Revision History.......................................................................................................................................52
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1. Overview of features
This 5W CW transceiver kit includes a large number of features defined by the firm are in the
ATmega328P microcontroller chip. The follo ing is a brief summary of the features to explore and
enjoy. Read the subsequent sections for more detailed information on these features.
Synthesised V O with rotary encoder tuning
The VFO is an Si5351A Synthesiser chip, configured by the microcontroller. A rotary encoder
tunes the VFO, ith a variable tuning rate. The radio includes t o VFOs, A and B. You can s ap
from one to the other, copy the contents of the active VFO to the inactive one, or operate Split
(Transmit on VFO A, receive on VFO B). There is also a RIT mode offering a receive offset of up
to +/- 9,999Hz. The CW offset is also adjustable, and CW-R (sideband s ap) mode is supported.
Memory features
There are 16 frequency presets for your favourite operating frequencies. Each frequency preset
can be edited in the configuration menu, or loaded/saved into/from the currently operating VFO.
Message mode
The firm are supports storage of 12 messages. Four of these are 100 characters long, the other
eight are 50 characters long. A single button click sho s the list of messages to send. Message
sending can be configured to send just once, or a configurable number of times, or indefinitely
repeating. The interval bet een transmissions is also configurable. The message feature can be
useful, for example, for setting up a repeated CQ call ith a pause bet een repeats, during hich
you can listen for any ans ers. As soon as you touch the key the message sending is canceled.
When message sending is in progress an ‘M’ character appears near the top right of the display.
CW Keyer
Operation ith a Straight key is possible, but the firm are also includes an Iambic keyer, for
connection of a paddle. The keyer can be configured to operate in Iambic modes A or B, or
Ultimatic mode. The keyer speed is variable both from the configuration menu and via a single
button press during operation.
With its solid-state, microcontroller operated transmit/receive s itch, the radio can operate in full
break-in “QSK” mode, or if you prefer, semi-break in.
CW Decoder
A CW decoder operates in the chip. This can be useful on air, particularly for ne comers to CW,
though it is never any here near as good in QRM or eak signal conditions as a good CW
operator using the et- are bet een his ears. The decoder has a “Practice” mode too, for you to
practice your CW sending ithout actually generating RF. The decoder can also be used to
conveniently enter text in the message storage, or for configuration of any of the other menu
items. The decoder can also be s itched off if desired.
CW, SKCW or WSPR Beacon mode
A beacon is included too, and this can be configured to operate in CW, FSKCW or WSPR mode.
O ners of the QRP Labs Ultimate-series eak signal mode transmitter kits ill be familiar ith the
operation of WSPR. A GPS module such as the QRP Labs QLG1 GPS receiver kit can optionally
be connected to this CW transceiver kit to provide frequency and time discipline, as ell as setting
the Maidenhead locator (from latitude and longitude) that is encoded in the WSPR message.
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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 ould be useful if you intend to operate
the radio portable on battery po er.
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 po er is
disconnected from the QCX, the time is lost and ill start at 00:00 at next po er-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 o n signal generator, injecting an appropriate signal into the receiver front end, then
measuring the audio amplitude after single-sideband demodulation. The menu items allo you to
easily peak the Band Pass Filter adjustment, and to adjust the I-Q balance and audio phase shift
adjustments for best un anted sideband cancellation.
Built-in test equipment
For those times hen the assembly didn’t quite go as ell as e hoped, and e need to do some
debugging – the radio includes its o n 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 ithout much test equipment, to debug the radio. They can even
be used for testing other projects too!
Voltage meter
RF Po er 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 Ken ood TS-480 command set, ith one or t o
minor exceptions.
It is intended to allo easy operation of the QCX in conjunction ith logging soft are, hich
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, hich 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 R 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.
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2. Display elements
The kit uses a 2 ro , 16 character LCD module. In the QCX and QCX+ models, this has a blue
backlight. The QCX-mini has a yello /green LCD module ith backlight that can be s itched off to
lo er current consumption.
The main display layout during ordinary operation ( hich ill be called “main operating mode”) is
sho n in the above photograph. The display during beacon or message transmission modes,
menu editing, alignment etc. differs. The main display elements are as follo s:
The receive VFO frequency is al ays displayed, to 10Hz resolution, at the top left. This
may be VFO A or VFO B. The nominally 700Hz CW offset is automatically applied.
Ordinarily this frequency is also used for transmission.
Tuning rate cursor: the underline appears under the digit hich is currently tuned by the
rotary encoder. In this example, the tuning rate is 100Hz per click, because the cursor is
under the 100Hz digit.
S-meter: these 4 characters display a basic (and not calibrated) S-meter. The scale is
configurable (see later description). The S-meter may be sho n or hidden.
Battery voltage: a battery icon appears to indicate the battery voltage in 7 user-definable
steps: from full to empty and 5 steps in bet een. It may also be sho n or hidden.
Transmit VFO: in SPLIT mode, the transmit VFO is displayed on the bottom ro of the
display.
RIT (Receiver Incremental Tuning): hen not in SPLIT mode, and hen the RIT is non-
zero, the RIT value is displayed in the bottom left ( here the photo sho s the VFO B
frequency). When RIT is non-zero, and hen not in SPLIT mode, the reception frequency is
the transmit VFO frequency ( hich may be VFO A or B) plus the RIT ( hich may be a
negative offset).
Decoded CW: The remaining space on the bottom ro is used for displaying the decoded
CW text. When RIT is zero, and you are not operating SPLIT, the hole 16 characters of
the bottom ro are used for the CW decoder display. When adjusting RIT or keyer speed,
only the right section of the screen is used for decoded CW. The CW decoder may be
disabled in the Decoder configuration menu.
Practice mode: hen in CW practice mode (actual transmitting disabled), a ‘P’ is displayed
to the right of the frequency on the top ro . If the practice mode as caused automatically
as a self-protection, by plugging in the GPS, a ‘G’ is displayed.
The bottom right 5 characters can also be used as a real time clock in HH:MM format,
hich is set either manually in the beacon menu “Set time” or via GPS serial data stream
parsing. The clock is enabled by the “Clock” item in the “Other” menu.
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3. Operator Controls
This diagram sho s the operating controls of the QCX+ radio as an example. All of the controls
except the Gain potentiometer have multiple functions, depending on the operating mode, menu
editing, etc. The tuning rotary encoder at the bottom right has a button on its shaft that is activated
by pressing it, and this button also has multiple functions.
In this document, the three buttons are referred to as “Select”, “Exit” and “Rotary”. The button
names “Select” and “Exit” respectively, refer to the common actions during configuration menu
editing. Select edits a menu item or steps do n into a sub-menu; Exit saves an edited menu item
or backs up to the parent menu.
It is ell orth remembering hile you are familiarising yourself ith the operation of the radio,
that if you get into any unexpected function or menu – you can nearly al ays press the “Exit”
button to cancel and get back to the main operation mode.
Each of the buttons may be pressed once, pressed t ice (a double-click) or pressed for a long-
hold. This facilitates three different functions for each button. In practice, the “Rotary” button is
stiffer and it is difficult to achieve a double-click; therefore the centre button double-click has no
function.
3.1 Tune rate
The rotary encoder tunes the active VFO. The rate of tuning is indicated by the underline cursor. In
the example belo , the underline cursor is under the comma bet een the 1kHz and 100Hz digits.
This means the tuning rate is 500Hz.
The available VFO tuning rates are 1kHz, 500Hz, 100Hz or 10Hz.
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A press of the “Rotary” button (in the rotary encoder shaft) causes the tuning rate to change, in the
cycle 1kHz -> 500Hz -> 100Hz -> 10Hz -> 1kHz etc.
The default tune rate up at start-up is a configuration item in the VFO menu (see later).
You can also press-and-hold the rotary encoder shaft button, then turn the rotary encoder to move
the cursor to the left or right; this allo s selection of steps up to 1MHz; turn the rotary encoder
ithin 0.3 seconds of the button press.
3.2 Keyer speed
The default keyer speed (in ords per minute) at start-up is a configuration item in the Keyer menu
(see later). During operation of the radio, the keyer speed can be easily adjusted. Click the
“Select” button once, and the speed ill be displayed on the screen:
A14,006,50
Speed 12
No you can adjust the speed using the rotary encoder. Press any button to return to the main
operating mode. You may operate the radio hile the Speed setting is sho n. You can also press
the rotary encoder shaft button to select sending a stored message, hile the Speed adjustment
setting is active.
Setting speed to 0 enables “Straight” Key mode regardless of the keyer mode setting; this is useful
for quickly being able to key do n for antenna tuning purposes. It is much easier than going into
the Keyer menu, selecting straight key mode, doing the tune up, then going back into the menu to
change to Iambic again. The normal configured keyer mode is automatically restored hen you
increase the speed above zero.
3.3 RIT
RIT (Receiver Incremental Tuning) allo s the receive frequency to be adjusted hile the transmit
frequency (the displayed VFO frequency) remains the same. It is useful if the other station is off-
tune, or drifting; other uses include orking DX stations ho may be listening on a different
frequency some kHz a ay from their transmit frequency.
This radio transceiver allo s RIT values from -9,999Hz to +9,999Hz.
The default RIT at start-up is a configuration item in the VFO menu (see later). RIT can be easily
adjusted during ordinary operation by double-clicking the “Select” button:
No use the rotary encoder to tune the RIT. As you do so, you ill hear the RIT immediately
applied to the VFO.
The tune rate of the RIT control is again indicated by the underlined digit (here 100Hz). In order to
change the tune rate, press and hold the “Rotary” button (in the rotary encoder shaft) and turn the
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rotary encoder at the same time. You ill see the cursor move to the left or right 1 digit at a time.
Again, the cursor under the comma indicates 500Hz tuning steps.
To cancel RIT tuning (reset the RIT to zero), press the “Exit” button; this returns to main operating
mode and sets the RIT to zero.
To return to the main operating mode, press the “Select” button. No the RIT is displayed under
the VFO, for example:
A14,060,00
+0,300
Remember that cancelling RIT mode is easy, just double-click the “Select” button to sho the RIT
editing, then press the “Exit” button to cancel it ( hich means, set it to zero).
Transmitting is possible hile the RIT display is active. You can also press the rotary encoder
shaft button to select sending a stored message, hile the Speed adjustment setting is active.
3.4 V O mode
A single press on the “Exit” button changes the active VFO mode. There are t o independent
VFOs named A and B. There are three VFO modes for using these VFOs:
VFO A is active as transmit and receive VFO; if non-zero, RIT is applied during receive
VFO B is active as transmit and receive VFO; if non-zero, RIT is applied during receive
Split: VFO A is used for receive, VFO B is used for transmit; RIT is ignored completely
Split mode is often used by DX stations, they transmit and receive on separate frequencies.
3.5 V O A/B operations
Frequency s ap: the contents (frequency) of VFO A and B can be s apped by a single long key-
press to the “Exit” button. This can be useful hen setting up the VFO frequencies.
Copy VFO A to B: To copy VFO A to B, press the “Exit” button ith a long key-press then a single
short press. It is similar to tapping a CW ‘N’ slo ly on the “Exit” button.
Copy VFO B to A: To copy VFO A to B, press the “Exit” button ith a long key-press then a quick
double-press. It is similar to tapping a CW ‘D’ on the “Exit” button.
3.6 requency Presets
There are 16 frequency presets hich may be used for storing your favourite frequencies, or for
just temporary use, or ho ever you ish!
The presets are labelled 1 to 16, and can be individually edited in the Preset menu (see later).
Often it is more convenient to just save them from the current VFO frequency.
To sho the list of preset frequencies in normal operation mode, double click the “Exit” button. The
display no sho s something like this:
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A14,027,50
S 1 14,035,00 L
The top ro of the display sho s the currently active VFO frequency as usual.
The bottom ro sho s a “1” in the 4th character, this is the number of the preset displayed. The
next number (here 14,035,00) is the frequency stored in Preset 1.
Use the rotary encoder to scroll through the list of presets until you find the one you ant. Once
you have selected the desired preset, press one of the three buttons to Save, Cancel or Load the
preset, as follo s:
SAVE the current VFO to the selected preset, by pressing the “Select” button
CANCEL the preset operation (back to main operating mode), by pressing “Rotary” button
LOAD the selected preset frequency into the current VFO, by pressing the “Exit” button
The “S” in the first character and “L” in the 16th character at the far right, are intended as a
reminder of hich button to press to Save and to Load.
3.7 Automated message transmission mode
My favourite use of the automated message transmission mode is to send a CQ call repeatedly. If
a station ans ers, you can tap the key to cancel the message sending mode, then transmit.
There are 12 message memories. The first four memories are 100 characters long; the remaining
eight memories are 50 characters long.
In order to send a pre-saved message, press the “Rotary” button ith a single long press. The first
of the saved messages is sho n on the screen, for example if a CQ call is stored in Message 1,
you may have something like this:
A14,017,00
1. CQ CQ CQ DE G
The bottom ro sho s the message number at the far left (here it is message 1) follo ed by the
first part of the stored message. If it is blank, that means of course that you have not stored any
messages yet!
You can no use the rotary encoder to scroll back and forth bet een the 12 stored messages and
find the one hich you ant to transmit.
The message can be transmitted multiple times according to the “Repeats” parameter in the
Messages menu (see later description). The interval bet een the repeated transmissions is also
defined in the Messages menu, in the “Interval” parameter.
Once you have selected the message that you ant to transmit, press one of the three buttons as
follo s:
REPEAT: Transmit the message repeatedly by pressing the “Select” button
ONCE: Transmit the message only once by pressing the “Rotary” button
CANCEL: Cancel the messages operation by pressing the “Exit” button
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When REPEAT message transmission mode is activated, the number of repeats and the interval
bet een repeats is as specified by the Repeats and Interval parameters in the Messages menu.
The stored message transmission is sent at the currently defined keyer speed.
During the actual stored message transmission, you can immediately cancel the transmission at
any time by pressing the “Exit” button or by keying the transmitter ith the Morse key or paddle if
you are using one.
While the RIT or Speed adjustment modes are active, you may still operate the radio (key the
transmitter) and may also press the rotary encoder center shaft button to initiate stored message
sending.
4. Menu System
There is an extensive menu system ith more than 80 different configuration or operating
parameters stored in non-volatile memory (EEPROM). These are editable to control every aspect
of the radio’s behaviour.
The menus are organised into 9 groups as follo s:
1. Preset
2. Messages
3. VFO
4. Keyer
5. Decoder
6. Beacon
7. Other
8. Alignment
9. Test equipment
Save settings!
To enter the menu system, give a single long press to the “Select” button. Use the rotary encoder
to scroll back and forth bet een the nine sub menu groups listed. To enter one of them, press the
“Select” button. To return to the main operating mode, press the “Exit” button.
The golden rule hile in the menu system, is to press the “Select” button to go in to a deeper
menu level or edit an item, and the “Exit” button to back up.
In order to edit a menu item, navigate to the menu item then press the “Select” button to start
editing. When you have finished editing the item, press the “Exit” button to save it.
NOTE that changes to configuration parameters only take effect on the radio, hen you leave the
menu system and return to the main operating mode. During vie ing or editing of menu items, the
radio remains in receive mode on the currently selected VFO frequency. The exception to this is
certain alignment and test equipment tools, here these need to use parts of the radio.
4.1 Saving current operating parameters (V O frequency etc)
The final (10th) item “Save settings!” is a special item hich causes certain operating parameters
to be stored to EEPROM. These then are the defaults the next time you po er up the radio. This
is very convenient if you ant to recommence operating next time you s itch on, ith exactly the
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