QRP Labs QMX User manual

QMX
QMX: QRP Labs Multimode Xcvr (transceiver)
Assembly manual
--- PCB Rev 1 ---
QMX assembly Rev 1.00e 1

Contents
Contents..........................................................................................................................................................................2
1. Introducon.................................................................................................................................................................3
2. Assembly.....................................................................................................................................................................5
2.1 General uidelines.................................................................................................................................................5
2.2 PCB dia rams (trace, component iden'caon)...................................................................................................9
2.3 Parts list...............................................................................................................................................................17
2.5 Install all the ceramic capacitors..........................................................................................................................23
2.6 Install 1N4007 diodes..........................................................................................................................................24
2.7 Install 47uH inductors..........................................................................................................................................25
2.8 Install BS170 PA transistors.................................................................................................................................26
2.9 Assemble and install transformer T501...............................................................................................................27
2.10 Prepare and install tapped inductor L401..........................................................................................................32
2.11 Wind and install L502........................................................................................................................................35
2.12 Install Low Pass Filter toroids............................................................................................................................36
2.13 Wind and install tri'lar toroid T401...................................................................................................................37
2.14 Wind and install transformer T507....................................................................................................................40
2.15 Install connectors..............................................................................................................................................41
2.16 Install pin header connector sockets (female)...................................................................................................42
2.17 Install power supply boards...............................................................................................................................43
2.18 Install LCD module.............................................................................................................................................47
2.19 Install 2x5-pin and 2x2-pin male pin header connectors...................................................................................48
2.20 Install four 11mm nylon spacers........................................................................................................................48
2.21 Install 20K trimmer potenometer R47.............................................................................................................49
2.22 Install 2x4-pin male header on controls PCB.....................................................................................................50
2.23 Install rotary encoders......................................................................................................................................51
2.24 Install tacle switch bu=ons..............................................................................................................................52
2.25 Install electret microphone...............................................................................................................................52
2.26 Install 11mm nylon hex spacer..........................................................................................................................53
2.27 Fit Controls PCB to main PCB.............................................................................................................................54
2.28 Plu to ether the boards...................................................................................................................................54
2.29 Oponal enclosure............................................................................................................................................56
2.30 QMX GPS interface and PTT output...................................................................................................................59
2.31 FINAL CHECKS BEFORE APPLYING POWER THE FIRST TIME!..............................................................................61
2.32 Connecons for basic operaon........................................................................................................................62
2.33 Firmware installaon.........................................................................................................................................63
3. Resources..................................................................................................................................................................66
4. Document Revision History.......................................................................................................................................66
QMX assembly Rev 1.00e 2

1 Introduction
The QMX is a high performance, five-band 5W CW and Digital modes transceiver with CAT
control and b ilt-in USB so nd card.
•80, 60, 40, 30 and 20m operation, with 5W from a 9V or 12V s pply (b ild options)
•Clean single signal o tp t (zero resid al carrier, zero nwanted sideband)
•S nlight viewable, large 16 x 2 character yellow/green LCD, switchable backlight
•B ilt-in SWR metering and protection
•Lightweight: 210 grams
•Solid state PIN-diode switched Low Pass Filters and solid state Band Pass Filters
•Solid state transmit/receive switching
•High performance embedded-SDR SSB receiver sing 112dB 24-bit stereo ADC chip
•B ilt-in USB so nd card: 48ksps 24-bit stereo
•B ilt in USB Virt al COM port serial for CAT control
•Si5351A Synthesized local oscillator with better than 0.001Hz resol tion and high precision
25MHz TCXO reference as standard
•B ilt-in signal generator
•B ilt-in s ite of config ration and analysis tools
•B ilt-in iambic keyer
•On-screen S-meter
•CW decoder
•CW: F ll or semi QSK, fast break-in; VFO A/B/Split, RIT, config rable offset, sidetone
•Beacon mode: standalone CW, FSKCW or WSPR operation
•GPS interface for real-time clock and freq ency discipline for WSPR operation
•Lifetime free firmware pgrades with QRP Labs Firmware Update (QFU) bootloader for
easy firmware pdate on any OS with no extra software, or drivers, or programming
hardware
•All SMD components pre-installed by factory, only thro gh-hole component soldering by the
kit constr ctor
•Low receive c rrent (switching b ck converters) 80mA; Transmit c rrent 1.0 – 1.1A
(transmit dependent on power s pply; example is approximately for 9V s pply, 5W o tp t)
•Connectors: USB-C (a dio and serial for CAT), Power, PTT (external amp), a dio o t,
paddle and RF
•Optional smart al mini m extr ded enclos re meas ring j st 95 x 63 x 25mm
No test eq ipment is req ired to b ild, align and operate this digi modes transceiver. All
adj stments can be made sing b ilt-in test eq ipment; or left alone (the transceiver will work well
even with no adj stment).
We hope yo enjoy b ilding and operating this kit! Please read this man al caref lly, and follow
the instr ctions step by step in the recommended order. The constr ction is necessarily very
compact and so it is important to really give attention to ALL the details described in this man al.
The circ it theory is described in detail in another doc ment and we recommend reading and
nderstanding this section too, to get the maxim m enjoyment and ed cation from yo r new radio.
The operating manual is a separate document and will get you started with QMX with CW,
or with your WSJT-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!
QMX assembly Rev 1.00e 3

IMPORTANT!
QMX can be built for 9V or 12V operation! You need to decide NOW!
A 9V QMX prod ces 5 W power o tp t from a s pply voltage of 9V or a little over. At 12V, a QMX
b ilt for 9V co ld be prod cing 8 W power o tp t which is likely to ca se over-heating and
perhaps fail re of the BS170 final transistors. Do not power a QMX with a higher voltage than yo
b ilt it for.
Operation of QMX at more than 5W power output is NOT RECOMMENDED
If yo wish to operate sing a 12 V s pply, yo may se a two t rn secondary winding on the
o tp t transformer T1, so a 3:2 ratio instead of the 3:3 t rns ratio doc mented in this man al.
Remember this when yo come to the assembly step for preparing and installing the o tp t
transformer T1. The “primary” is still 3 t rns, with a tap half way at 1.5 t rns. The secondary (no
tap) will now be only two t rns.
The chart below shows the meas red power o tp t vs s pply voltage for the standard 3:3 winding
(Red line); at 12 V s pply the o tp t power of aro nd 8 W is too high and likely to ca se over-
heating or fail re of the power amplifier transistors. If yo wish to se a s pply of 12 - 13 V the 3:2
winding style is more s itable and will prod ce 4 – 5 W o tp t for 12 – 13 V s pply. The graph
shows 40m b t other bands are very similar.
Operation at more than 12V will red ce the protection safety margin available in the event of very
long key-downs, hot environment, antenna mismatch, cable fa lts etc. I don’t recommend more
than 12V. It isn’t worth p shing more j st for a fraction of a dB. It is acceptable to se diodes in
series on the power line, each one will drop the voltage 0.6V or so. Beware that a 12V nominal
battery will potentially be several volts higher when f lly charged.
QMX assembly Rev 1.00e 4

2 Assembly
2 1 General guidelines
Assembly of this kit is q ite straightforward, b t very detailed; most components are SMD and
have already been pre-assembled by the PCB factory. The s al kit-b ilding recommendations
apply: work in a well-lit area, with peace and q iet to concentrate. Some of the other
semiconductors in the kit are sensitive to static discharge Therefore, observe Electrostatic
discharge (ESD) precautions.
And I say it again: FOLLOW THE INSTRUCTIONS!!
Don’t try to be a hero and do it witho t instr ctions!
A jeweler's lo pe is really sef l for inspecting small
components and soldered joints. Yo ’ll need a fine-
tipped soldering iron too. It is good to get into the habit of
inspecting every joint with the magnifying glass or
jeweler's lo pe (like this one I se), right after soldering.
This way yo can easily identify any dry joints or solder
bridges, before they become a problem later on when
yo are trying to test the project.
Yo co ld also take photos with a mobile phone, and se the phone’s zoom feat res to view the
board in detail.
Triple check every component value and location BEFORE soldering the component!
It is easy to p t component leads into the wrong holes, so check, check and check again! It is
diffic lt to de-solder and replace components, so it is m ch better to get them correctly installed
the first time. In the event of a mistake, it is always best to detect and correct any errors as early
as possible (immediately after soldering the incorrect component). Again, a reminder: removing a
component and re-installing it later is often very diffic lt! This is partic larly tr e on this QMX
design where the components m st be installed very close together.
Please refer to the layo t diagram and PCB tracks diagrams below, and follow the steps caref lly.
Use of a good quality soldering iron and solder is highly recommended for best results!
The following diagrams show the PCB layo t and track diagrams of the QMX.
6-layer PCB
QMX is a 6-layer PCB. This means that there are two internal gro nd-planes and two internal
signal layers, in addition to the normal top and bottom signal layers. This is necessary in order to
achieve the req ired component density in the QMX design, as well as to achieve the req ired
gro nd-plane, signal gro nd ret rn paths necessary to deliver low-noise and high performance
with s ch a high component density in a mixed mode (analog/digital) board.
Because of the internal layers it is essential that you never ever drill into the PCB; just
because you think you see a clear spot on the top and bottom layers, does NOT mean that
there is nothing hidden in the middle
There sho ld never be any reason to drill into the board anyway b t I’m j st saying, in case for
some pec liar reason yo feel an irresistible temptation to go wild.
QMX assembly Rev 1.00e 5

Tracks shown in BLUE are on the bottom layer. Tracks shown in RED are on the top layer. One
internal layer is sed mainly for transporting digital and analog signals relatively long-distance on
the board, and these traces are shown in YELLOW. One layer is sed primarily (b t not
excl sively) for power rails (12V, 5V, 3.3V). These traces are shown in PURPLE. Two of the
internal layers are sed ONLY for gro nd-plane with no exceptions. Additionally, all n- sed area
on ALL the layers, is assigned as gro nd-plane wherever possible, with freq ent gro nd plane
stitching vias connecting the layers on all 6 planes, at intervals not more than 0.1 inches.
For best RF low noise performance, any signal transitioning between layers sho ld have a nearby
gro nd via stitching the gro nd-planes together, placed as close as possible, to minimize
emissions d e to discontin ity of the gro nd ret rn paths. Freq ent gro nd plane stitching also
prevents the creation of internal microwave cavities which co ld resonate and enhance noise
propagation between harmonics of digital signals and sensitive RF signals.
This diagram from the Eagle CAD “Design R les Check” ill strates the layer set- p which is based
on the specification of the PCB man fact rer.
Yo will note that there is only one type of via, which goes thro gh the entire board thro gh all 6
layers. In many cases, a signal act ally only needs to transition part-way thro gh the board, for
example from the bottom layer (16) to the internal signal layer (3). Other types of via are possible,
which are called “blind” and “hidden” or “b ried” vias.
Blind via: has one end on the board s rface layers, and drills thro gh to an internal layer where it
terminates. It does not have a drill hole all the way thro gh the board, so other components and
traces co ld be placed on the opposite board s rface or on internal layers witho t conflict.
QMX assembly Rev 1.00e 6

Hidden or b ried via: neither ends of the via are visible on either s rface; the via transitions signals
entirely between internal layers only.
Unfort nately a 6-layer board is m ch more expensive than a 2-layer board; and if yo se blind or
hidden vias the costs escalate even more drastically. For this reason, no blind or b ried vias are
sed in the QMX. It is necessary to se a 6-layer board, b t the design is not so complex or
compact that blind or b ried vias are needed.
NOTE: the capacitor lead spacing on the PCB is 0.1-inches (2.54 mm) and most of the capacitors
are sized appropriately for this. From time to time, d e to availability constraints, we may have to
se capacitors with 0.2-inch lead spacing (5.08 mm); this is not a mistake, it is j st d e to
component availability. In this case simply se a pair of long-nosed pliers (etc) to straighten o t
the wires and make them spaced for the 0.1-inch pads.
Board structure
The QMX PCB is on a single panel, which m st be broken apart very caref lly into smaller pieces.
Do not lose any of the pieces, some of which are q ite small. Take great care not to damage any
of the small boards. The following page shows a diagram of the PCB panel, with the
constituent parts outlined in red
The easiest way to break o t the boards is to se needle-nosed pliers or wire-c tters, grab each of
the breakaway tabs colored in yellow, and gently twist it to remove it from the panel, leaving only
the wanted small PCBs. The rough edges must be filed flat carefully, taking care not to
damage any nearby SMD components, particularly applicable to the small power supply
boards The tiny control board spacers don’t partic larly need the ro gh edges filed.
The large PCB panel s pplied is broken o t into the following pieces:
•LCD board: This is the top board of stack, the LCD mod le is bolted and soldered to it.
•Controls board: breaks o t of the LCD board, holds the rotary encoders and b ttons
•Controls board spacers: two tiny boards, also part of the LCD board; these are very
important to obtain the correct height of the controls board; be caref l not to lose them!
•Main board: the main PCB of the QMX with most of the components, on both sides.
•Power supply boards: two PCBs that have the 5V and 3.3V b ck converters, reverse
polarity protection, soft power switch, and 3.3V linear reg lator. The board shapes are
irreg lar, be caref l not to break any small protr sions.
•Keyfob: QRP Labs fashion: break this o t, file the edges smooth, and p t it on yo r key-
ring; enjoy yo r QRP Labs keyfob with pride
QMX assembly Rev 1.00e 7

QMX assembly Rev 1.00e 8

Tips for a successful build:
1. READ the man al, and every instr ction caref lly! Don’t try to be a hero (proceed witho t
reading caref lly). There are many more people who will need to b y a new board, than
real heroes…
2. Don’t r sh! Take yo r time!
3. Use good lighting!
4. Use a jeweler's lo pe to check component val es of capacitors BEFORE soldering.
5. Use a soldering iron with a fine tip and high power. For example 60W
6. When soldering capacitors (and other components), note that where pins are gro nded,
these typically need a lot more heat to ens re a good clean joint. A common error is poorly
soldered gro nd connections of LPF capacitors, which ca ses incorrect filter performance
(often manifested as low power o tp t).
7. When soldering and clipping component leads, be very caref l of nearby SMD components
which co ld easily be damaged. Before soldering/clipping, identify nearby SMDs, then
make s re that yo approach the lead to be soldered or clipped from the opposite direction
to the nearby SMD component.
8. KEEP the component lead offc ts from the capacitors – they are sed later when installing
the LCD mod le.
9. Solder connectors with no more heat and time necessary to create a good solid clean joint
to avoid melting the plastic body parts of the connectors.
10.Remember diodes MUST be connected the correct way ro nd!
11.After every joint, inspect with the jeweler's lo pe to check for a good clean joint and any
solder bridges to any nearby components: a lot of the components are packed very close
together.
12.Clip all components leads as short as possible to avoid any shorts to the enclos re on the
nderside of the board.
13.Install all connectors sq are and well-seated on the boards, to ens re when the boards are
pl gged together and installed in the enclos re, everything fits properly.
14 Don’t forget: QMX is supplied without firmware Therefore at first power-up, you
must install the latest firmware, a very simple procedure which is described in
section 2 32
2 2 PCB diagrams (trace, component identification)
S bseq ent pages show the trace and component identification diagrams for the vario s QMX
PCBs.
QMX assembly Rev 1.00e 9

QMX assembly Rev 1.00e 10

QMX assembly Rev 1.00e 11

QMX assembly Rev 1.00e 12

Trace layo t:
Top side components:
Bo=om side components:
LCD and controls board are on the followin pa e; there are no SMD components on the bo=om side of
these boards.
QMX assembly Rev 1.00e 13

QMX assembly Rev 1.00e 14

QMX assembly Rev 1.00e 15

QMX assembly Rev 1.00e 16

2 3 Parts list
Component nomenclat re is by schematic sheet. Part n mbers
•1xx Power s pply boards, schematic page 1
•2xx Main board, CPU etc., schematic page 2
•3xx LCD board and controls board, schematic page 3
•4xx Main board, receiver section, schematic page 4
•5xx Main board, transmitter section, schematic page 5
Many components are SMD, pre-soldered to the PCB in the factory. Only thro gh-hole
components need to be installed by the constr ctor. SMD components in the parts list are
identified in the Description col mn and by the text colo r being p rple.
Resistors
Qty Value Description Component numbers
14 100k SMD 0603 R101，R103，R104，R105，R108，R109，R208，
R209，R212，R502，R503，R518，R521，R523
19 1kK SMD 0603 R102，R106，R107，R204，R213，R214，R215，
R216，R401，R402，R405，R406，R501，R505，
R508，R510，R519，R524，R526
7 22k SMD 0603 R110，R111，R112，R113，R206，R423，R424
5 47-ohms SMD 0603 R114，R415，R418，R419，R422
4 1k SMD 0603 R201，R202，R515，R517
2 47k SMD 0603 R203，R525
2 220-ohms SMD 0603 R205，R210
4 470k SMD 0603 R207，R511，R512，R513
3 2.2k SMD 0603 R211，R217，R218
4 3.3k SMD 0603 R301，R304，R409，R410
1 6.8k SMD 0603 R302
1 13k SMD 0603 R303
1 33-ohms SMD 1206 R306
2 267k SMD 0603 R403, R404
2 560-ohms SMD 0603 R407, R408
3 5.6k SMD 0603 R411, R412, R507
2 100-ohms SMD 0603 R413, R414
4 470-ohms SMD 0603 R416，R417，R420，R421
2 5.1k SMD 0603 R504, R506
1 1.91k SMD 0603 R509
2 33-ohms SMD 0603 R514, R516
2 49.9-ohms SMD 0603 R520, R522
1 20K TRIM3339P Trimmer R305
QMX assembly Rev 1.00e 17

Capacitors (50V, M lti-layer Ceramic capacitors except where indicated otherwise)
(see below for listing of band-version dependent inductors)
Qty Value Description Component numbers
15 2.2 SMD 0603 C101，C102，C103，C104，C105，C215，C216，
C406，C407，C408，C413，C414，C430，C434，
C510
2 470 6.3V tantal m C106, C107
32 0.1 SMD 0603 C201,C202,C203,C204,C206,C207,C208,C209,C210,
C211,C212,C214,C217,C219,C301,C409,C410,C415,
C428,C429,C436,C438,C501,C503,C507,C508，C50
9，C513，C526，C527，C528，C529
3 47n SMD 0603 C205，C411，C412
3 1 SMD 0603 C213，C405，C506
3 1n SMD 0603 C218，C220，C505
4 33n SMD 0603 C416，C417，C418，C419
3 10 SMD 0805 C420，C421，C502
4 4.7n SMD 0603 C422，C423，C424，C425
2 10n SMD 0603 C426，C427
4 10 Tantal m case A style C431，C433，C435，C439
2 1 Tantal m case A style C432，C437
1 470 Electrolytic 10V C504
2 47p SMD 0603 C511，C512
Semiconductors
Qty Description Component numbers
9 SMD: 1N4148 SOD323 D101，D102，D103，D104，D105，D501，D505，
D506，D507
5 SMD: SS14 DO-214AC D106，D107，D502，D514，D515
6 1N4007 diode D508, D509, D510, D511, D512, D513
2 Un sed diode D503, D504
1 SMD: 5.6V 500mW SOD-123 D108
1 SMD: 3.6V 500mW SOD-123 D109
1 SMD: 78M05 TO252 IC101
1 SMD: 24M01 SOIC-8 IC201
1 SMD: SN74AHC1G00DBV IC202
1 SMD: STM32F446VET6 IC203
1 SMD: MS5351M IC204
1 SMD: CS4334 SOIC-8 IC401
2 SMD: 74CBT3253 SOIC-16 IC402, IC403
1 SMD: NE5532 SOIC-8 IC404
2 SMD: LM4562 IC405, IC406
1 SMD: PCM1804 IC407
QMX assembly Rev 1.00e 18

Qty Description Component numbers
2 SMD: 74AHC1G86DBV IC501, IC502
1 SMD: 74ACT08 SOIC-14 IC503
4 SMD: BSS84 MOSFET Q102，Q202，Q204，Q502
12 SMD: BSS123 MOSFET Q101，Q104，Q106，Q107，Q110，Q203，Q301,
Q501，Q508，Q509，Q510，Q511
5 SMD: BC817 NPN SOT23-3 Q12，Q13，Q14，Q112，Q113
2 SMD: BC857 PNP SOT23-3 Q15，Q16
4 BS170: TO92 MOSFET Q503, Q504, Q505, Q506
3 SMD: AO3415A SOT23-3 Q108，Q109，Q111
3 SMD: AOD403 (TO252) Q103，Q105，Q507
1 SMD: 25MHz TCXO mod le TCXO
Inductors
(see below for listing of band-version dependent inductors)
Qty Description Component numbers
5 SMD: 47 H L2012 L201，L202，L402，L503，L504
3 SMD: 330 H (CD54) L101，L102，L501
4 47 H axial ind ctor L505, L507, L509, L514
2 FT37-43 L502, T401
1 BN43-202 binoc lar, 3:3 T501
1 BN43-1502 binoc lar T507
Miscellaneous
Qty Value Description
1 2.1 mm DC 2.1 x 5.5 barrel DC power connector
1 USB C USB type C connector
1 BNC Metal RF connector
3 3.5mm jack 3.5mm Stereo connector (PTT)
2 2x4 Pin header connector socket (female)
1 2x4 Pin header connector 90-degree pl g (male)
1 2x3 Pin header connector socket (female)
1 2x3 Pin header connector 90-degree pl g (male)
1 2x5 Pin header connector socket (female)
1 2x2 Pin header connector socket (female)
1 2x4 Pin header connector 17mm long pl g (male)
1 2x2 Pin header connector pl g (male)
1 2x5 Pin header connector pl g (male)
1 PCB Main PCB, 92 x 139.4 mm
1 1602 LCD 80x36mm HD44780 LCD mod le yellow/green
QMX assembly Rev 1.00e 19

Qty Value Description
1 6mm Electret Microphone
2 Rotary Rotary encoder switch
2 6x6x8mm P sh-b tton switch
2 15mm Knob
1 365 cm (80-20m version) 0.33 mm diameter wire (AWG #28)
(varies depending on QMX version as noted)
1 65 cm (80-20m version) 0.60 mm diameter wire (AWG #22)
(varies depending on QMX version as noted)
1 M3 12 mm Steel 12mm long M3 screw
1 M3 Steel M3 n t
1 M3 12 mm Steel 12mm diameter M3 washer
5 M3 x 11mm Nylon threaded hex spacer
12 M3 x 6mm Nylon screw
2 M3 x 9mm Nylon screw
6 M3 Nylon n t
Enclosure (OPTIONAL)
Qty Value Description
1 Top Extr ded al mini m top, c t, drilled and laser-etched
1 Bottom Extr ded al mini m bottom
1 Left panel Laser etched, drilled for three connectors
1 Right panel Laser etched, drilled for three connectors
8 M2.5 machine screw Screws to sec re end panels
4 R bber foot Self-adhesive r bber foot
QMX assembly Rev 1.00e 20