QRP Labs QMX User manual

QMX
QMX: QRP Labs Multimode Xcvr (transceiver)
Operating manual, firmware .00_0 2, 05-Dec-2023
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Contents
1. Overview of features...................................................................................................................................................4
2. Conne tors..................................................................................................................................................................7
3. Display elements.......................................................................................................................................................10
4. Operator Controls.....................................................................................................................................................11
4.1 Tune rate.............................................................................................................................................................12
4.2 Keyer speed.........................................................................................................................................................12
4.3 RIT........................................................................................................................................................................13
4.4 VFO mode............................................................................................................................................................13
4.5 VFO A/B operaons.............................................................................................................................................14
4.6 Frequen y Presets...............................................................................................................................................14
4.7 Automated message transmission mode............................................................................................................14
5. Menu System.............................................................................................................................................................15
5.1 Saving urrent operang parameters (VFO frequen y et ).................................................................................16
5.2 Types of onguraon menu item.......................................................................................................................16
5.3 Eding a onguraon menu parameter.............................................................................................................16
5.4 Eding a LIST parameter......................................................................................................................................17
5.5 Eding a BOOLEAN parameter............................................................................................................................17
5.6 Eding a NUMBER parameter..............................................................................................................................17
5.7 Eding a TEXT parameter....................................................................................................................................18
5.8 Audio menu.........................................................................................................................................................19
5.9 Frequen y presets menu.....................................................................................................................................20
5.10 Messages menu.................................................................................................................................................20
5.11 Keyer menu.......................................................................................................................................................21
5.12 CW De oder menu.............................................................................................................................................25
5.13 Digi interfa e.....................................................................................................................................................27
5.14 Bea on menu.....................................................................................................................................................29
5.15 Display/ ontrols menu.......................................................................................................................................36
5.16 Prote on menu................................................................................................................................................40
5.17 System ong....................................................................................................................................................41
5.18 Hardware tests..................................................................................................................................................46
5.19 Fa tory Reset.....................................................................................................................................................47
5.20 Update rmware...............................................................................................................................................48
6. Operang QMX on digital modes..............................................................................................................................49
7. Firmware Update pro edure.....................................................................................................................................56
8. Terminal Appli aons................................................................................................................................................60
8.1 PC terminal emulator..........................................................................................................................................60
8.2 Entering terminal appli aons mode..................................................................................................................61
8.3 Exing terminal appli aons mode....................................................................................................................61
8.4 Conguraon menu.............................................................................................................................................62
8.5 Band onguraon.............................................................................................................................................63
8.6 Hardware tests menu.........................................................................................................................................65
8.6.1 Audio lter sweep............................................................................................................................................66
8.6.2 RF lter sweep.................................................................................................................................................67
8.6.3 Image sweep....................................................................................................................................................69
8.6.4 SWR sweep......................................................................................................................................................71
8.6.5 Diagnos s........................................................................................................................................................71
8.6.6 GPS viewer.......................................................................................................................................................74
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8.7 PC and CAT menu...............................................................................................................................................76
8.7.1 System ong...................................................................................................................................................77
8.7.2 Input Analysis.................................................................................................................................................. 77
8.7.3 CAT ommand test...........................................................................................................................................81
8.7.4 CAT monitor.....................................................................................................................................................86
8.7.5 Log le.............................................................................................................................................................86
8.8 System menu......................................................................................................................................................89
8.9 Exit terminal........................................................................................................................................................89
9. Resour es..................................................................................................................................................................90
10. Do ument Revision History.....................................................................................................................................90
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. Overview of features
QMX is a high performance, five-band multi-mode 5W QRP transceiver kit, which implements a
sophisticated DR receiver in a 168MHz 32-bit ARM Cortex M4 microcontroller ( TM32F446).
Most of the features are implemented digitally in firmware, and the feature set is continuing to be
expanded by ongoing firmware development. Please refer to the later section on planned future
functionality. This section provides a brief summary of the features to explore and enjoy.
QMX is highly portable
The small size and very low receive current consumption (as low as 80mA) are key features of
QMX, making it an ideal transceiver for portable operations including OTA and POTA activations.
QMX is a standalone CW transceiver, or a Digimodes modem
You can use QMX on its own, plugging in earphones, power supply, paddle and antenna and
operating CW; or, you can connect it to a PC with a single U B-C cable, to provide CAT control
and Digital audio to the PC and use it with W JT-X or other programs for single-tone F K digital
modes (not suitable for P K31 and phase shift modes until B is implemented).
Synthesised VFO with rotary encoder tuning
The VFO is an i5351A or M 5351M synthesiser chip, configured by the microcontroller. A rotary
encoder tunes the VFO, with a variable tuning rate. The radio includes two VFOs, A and B. You
can swap from one to the other, copy the contents of the active VFO to the inactive one, or
operate plit (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 swap) 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 firmware supports storage of 12 messages. Each of these are 50 characters long. A single
button click shows 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 between
transmissions is also configurable. The message feature can be useful, for example, for setting up
a repeated CQ call with a pause between repeats, during which you can listen for any answers. 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 with a traight key is possible, but the firmware 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 via a single button press during operation.
Full or semi break-in
With its solid-state, microcontroller operated transmit/receive switch, the radio can operate cleanly
in full break-in “Q K” mode, or if you prefer, semi-break in.
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CW Decoder
A CW decoder operates in the microcontroller. This can be useful on air, particularly for
newcomers to CW, though it is never anywhere near as good in QRM or weak signal conditions as
a good CW operator using the wet-ware between his ears. The decoder has a “Practice” mode
too, for you to practice your CW sending without 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 switched off if desired.
CW, FSKCW or WSPR Beacon mode
A beacon is included too, and this can be configured to operate in CW, F KCW or W PR mode.
Owners of the QRP Labs Ultimate-series weak signal mode transmitter kits will be familiar with the
operation of W PR. A GP module such as the QRP Labs QLG2 GP receiver kit can optionally
be connected to this CW transceiver kit to provide frequency and time discipline, as well as setting
the Maidenhead locator (from latitude and longitude) that is encoded in the W PR message.
S-meter and Battery voltage
An -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. Battery voltage range warning can be configured and
prevention of transmit if out of range.
SWR measurement
Built-in WR bridge always in-line, continuously measures WR and power output; these can be
configured to show on the display, and a configurable bad- WR threshold to prevent transmit is
available.
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 GP receiver such as the QRP Labs QLG2 temporarily to the QMX. When power is
disconnected from the QMX, the time is lost and will start at 00:00 at next power-up.
Built-in high performance 48ksps 24-bit USB soundcard
No more audio hum ground loops, or lossy noisy connections; a simple U B cable connection to
the PC is all that is required for perfect lossless noise-free, hum-free audio transfer back and forth
between QMX and the PC.
CAT control - PC Control commands
The same U B connection also implements a Virtual COM serial port for CAT control commands.
This implements a subset of the Kenwood T -480 command set, with one or two minor additions
and exceptions.
It is intended to allow easy operation of the QMX 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 QMX if
required, and is used by software such as WXJT-X when in digital mode, to control the operating
frequency and manage transmit/receive switching.
Rich terminal interface
The Virtual COM serial port connection can be used with a Terminal emulator such as PuTTY, to
access a range of configuration, alignment and debug tools within QMX, all delivered over the
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serial terminal interface. There are additional serial ports which may be enabled at a later time
(firmware enhancement). The complete configuration menu is from the terminal too. Alignment
tools include an RF sweep tool which uses the QMX’ own internal signal generator injected into
the RF port, to sweep across the band pass filters so you can check whether the performance is
optimal and make adjustments if desired.
GPS Interface
The QMX kit has a GP interface, which is used for calibration, setting the real time clock, and for
frequency and time discipline and locator setting during W PR operation. The GP 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 style of this interface is the same as the earlier
QCX-series CW transceiver kits.
The GP should only be connected during calibration functions or when the beacon is enabled.
Connection at other times puts the radio into practice mode (no RF emitted) to protect the PA. You
may temporarily connect the GP while in ordinary operation mode, for the purposes of setting the
real time clock.
QRP Labs Firmware Update
A special feature of QRP Labs kits based on TM32-series microcontrollers is the QRP Labs
Firmware Update procedure (QFU). In firmware update mode, the radio appears to a U B-
connected PC as a U B Flash drive. Updating the firmware is a simple matter of downloading the
new firmware file, unzipping it, and copying it into QMX. Firmware updates will always be free.
They will deliver performance and functionality enhancements and bug fixes.
ASSEMBLY
Assembly of the transceiver is covered in a separate document.
Note: QMX PCB Rev 2 should be used with firmware _00_0 and above.
This document describes operation of QMX, and applies to the firmware version specified. This
manual will get you started with QMX, either as a standalone CW transceiver or with your W JT-X
or other digi modes software in minutes.
PLEASE READ THE BASIC ASSEMBLY AND USE INSTRUCTIONS IN
THIS MANUAL VERY CAREFULLY BEFORE APPLYING POWER TO
THE BOARD!
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2. Connectors
This is the QMX left panel.
Paddle connector
The paddle connector is a 3.5mm stereo jack socket and actually has THREE purposes:
1) Paddle for CW operation
Don’t worry if your paddle has a reversed pinout, or if you connect the dit and dah to a 3.5mm jack
plug incorrectly: there is a configuration item in the configuration menu (CW Keyer menu) allowing
you to swap the dit and dah in the firmware.
2) GP interface
Here the 1pps signal from the GP must be connected to the 3.5mm jack “tip” connection, and the
serial data (9600 baud) to the “ring” connection. In QMX these signals are 3.3V logic level;
however they are connected to 5V-tolerant I/O pins on the microcontroller so 5V logic level will
also work fine. If you are using a GP module directly, and it has the common 2.8V output logic,
this will also work fine.
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Note that the QMX cannot supply +5V to the GP module power supply, and in this regard the
GP interface differs from that of the QRP Labs QCX-series transceivers. o you need to arrange
a separate 5V power supply for the QLG2 GP (for example).
3). Microphone interface
In B mode, an electret microphone and PTT switch may be connected to the Paddle port.
An internal +2.2K pullup to +3.3V is provided to power electret microphones.
Audio connector
The audio output connector is a standard 3.5mm stereo jack socket for connecting 32-ohm
earphones or similar. It is not suitable for driving a loudspeaker directly. QMX internally controls
the Left and Right channels separately which makes future interesting functionality possible.
DC connector
The DC connector is a 2.1mm barrel jack connector, the same as used on other QRP Labs
transceiver kits such as QCX+, QCX-mini and QDX.
The center pin is positive, the barrel is ground.
The supply voltage range for QMX is 6.0 to 12.0V. Maximum power output depends on the supply
voltage.
This is the QMX right panel.
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RF connector
The RF connector is a 50-ohm BNC connector securely bolted to the enclosure. QMX should be
used with reasonably well-matched 50-ohm loads. Note that the WR bridge inside QMX means
that there is a DC connection to ground; if you measure using a DVM continuity or ohm-meter
between the center pin and ground, you will measure zero ohms. This also means that no
additional bleeder resistors are required across a connected resistor, to bleed away static charge
buildup.
PTT connector
The PTT connector is a 3.5mm stereo jack socket.
There are separate active grounded and active +5V outputs. The conventional way to control
external amplifiers is with a grounded PTT. However the QRP Labs 50W PA kit requires a +5V
active (Transmit) PTT control signal. o this PTT output connector is capable of providing both
styles of PTT connection.
The two outputs can be configured individually per band, in the Band Configuration menu.
Additionally they may be configured to also be active during receive – which may be used to
control some external switching for example.
Note that the two outputs have 220-ohm resistors in series, to protect internal QMX circuits in the
case of short-circuits.
USB connector
The U B connector is a U B-C type connector. When connected to a host PC, QMX appears as
both a U B sound card (24-bit 110dB 48ksps) and a Virtual COM erial port used for CAT control
and accessing the terminal applications. It therefore effectively emulates a U B hub, with two
devices connected (U B sound card, and erial).
Additionally the U B connection is used during bootloader mode, when the QMX appears for
firmware update purposes as a U B Flash drive (see later section on firmware update).
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3. Display elements
The kit uses a 2 row, 16 character LCD module, with black text on a yellow/green background.
There is a backlight which can be switched off if desired, to save a few mA of current
consumption. The display has a large, easy to read font, and is perfectly readable in bright sunlight
with no backlight.
The main display layout during ordinary operation (which will be called “main operating mode”) is
shown in the following photograph. The display during beacon or message transmission modes,
menu editing, alignment etc. differs. The main display elements are as follows:
The receive VFO frequency is always displayed, to 10Hz resolution, at the top left. This
may be VFO A or VFO B. In CW mode the nominally 700Hz CW offset is automatically
applied. Ordinarily in CW mode, the displayed frequency is also used for transmission.
Tuning rate cursor: the underline appears under the digit which 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.
Practice mode: when in CW practice mode (actual transmitting disabled), a ‘P’ is displayed
to the right of the frequency on the top row. If the practice mode was caused automatically
as a self-protection, by plugging in the GP , a ‘G’ is displayed. During saved message
transmissions, this character is set to ‘M’ and in ordinary operation, it is blank.
Mode indicator: this single character indicates the current operating mode of the tranceiver;
in the example in this photograph it is “CW”.
-meter: these 3 characters are configurable and display the -meter/ WR/Power meter.
Battery voltage: a battery icon appears to indicate the battery voltage in 7 user-definable
steps: from full to empty and 5 steps in between. It may also be shown or hidden.
Transmit VFO: in PLIT mode, the transmit VFO is displayed on the bottom row of the
display.
RIT (Receiver Incremental Tuning): when not in PLIT mode, and when the RIT is non-
zero, the RIT value is displayed in the bottom left (where the photo shows the VFO B
frequency). When RIT is non-zero, and when not in PLIT mode, the reception frequency is
the transmit VFO frequency (which may be VFO A or B) plus the RIT (which may be a
negative offset).
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