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Introduction to the QRP-Labs QMX+ Multi-mode Transceiver

Carol Milazzo, KP4MD

River City ARCS

January 7, 2025

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But First, a few DIY-Radio Updates

Tuna Tin S Project

  • 7 MHz ½ watt �CW transmitter
  • Arduino Nano
  • Digital Frequency Synthesizer
  • $25 kit in 2021

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Tuna Tin S QRPp Transmitter

The Tuna Tin S �only puts out �½ watt but the �IRF510 transistor �is capable of �more power and better efficiency.

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A New MOSFET Driver Stage

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Tuna Tin S MOSFET Driver Stage

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Tuna Tin S Output Is Now 5-7 Watts

This modification raises the transmitter power �to 5 to 7 watts.

An add-on daughterboard is under development.

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Tuna Tin S Software Update

We rewrote the Arduino Nano code to cover all the �HF amateur bands, �but the transmitter board only has one on-board band filter.

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Sockets Replace the Onboard Filter

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Before After

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Tuna Tin S is now Multi-Band

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7W on 3.5, 5.3 & 7 MHz, 4W on 10 MHz, 2.2W on 14 MHz

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Raspberry Pi PicoRX Project

  • Raspberry Pi Pico microcontroller SDR
  • 1-30 MHz, AM, FM SSB, CW modes
  • Spectrum & waterfall displays
  • USB CAT control and audio

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Raspberry Pi PicoRX Project

  • Operates off �3 AAA cells or �5V USB cable
  • Kit build time �~ 3 hours
  • Est. kit cost ~$30

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Demo Video

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Raspberry Pi PicoRX Project

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Introduction to the QRP-Labs QMX+ Multi-mode Transceiver

Carol Milazzo, KP4MD

River City ARCS

January 7, 2025

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Hans Summers, GØUPL

  • WHEREAS, Hans Summers, GØUPL has developed modular cutting-edge high performance QRP transceiver kits with advanced features with state-of-the-art performance;
  • WHEREAS, his designs and kits provide a low cost and effective means of entry into amateur radio worldwide;
  • and WHEREAS, his kit QRP-Labs QMX transceiver kit is capable of multiple modes over a large frequency range.
  • THEREFORE, the ARRL Board of Directors does bestow The 2024 ARRL Technical Innovation Award �to Hans Summers, GØUPL.

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Hans Summers, GØUPL

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QRP-Labs Kit store

www.qrp-labs.com

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Hans’ Lab Notebook

www.hanssummers.com

Interview: https://www.qsotoday.com/podcasts/g0upl

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QRP Labs Beginning - 2012

The Ultimate QRSS

- QRSS CW mode

- FSK/CW mode

- DFCW mode

- WSPR mode

- Slow-Hellschreiber

- Full-speed Hellshreiber

- Half-speed ("DX") Hellshreiber

- CW (plain CW)

- Customisable FSK patterns

- 150 milliwatts output

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QRP-Labs QCX (2017)

5 Watt Single-band

CW Transceiver

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160-6m CW/DIGI

(SSB is coming)

4-5 Watts out

Requires 7-12V

80mA receive 1A transmit

Internal soundcard & CAT

control over 1 USB cable

IQ output available

SWR bridge/protection

Built in test tools

Internal beacon mode

GPS option

SDR

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The QCX & Bitx Families

QCX

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QDX trUSDX

QMX+ QMX USDX+ zBitx

µB

i

t

x

Bitx40

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YouTube “Bluesmother”

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Delivered in 6 days via US Mail

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Kit Building Tools

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Use a Hot Fine Tip Soldering Iron

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Day 1 - Inventory

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Day 2 - 32 Capacitors

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Day 3 - PIN diodes, PA transistors

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Day 4 - Output Xfmr & 2 Toroids

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Day 5 - Inductor mania!

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Inductor mania!

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Final Day Assembly

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Install in Enclosure

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Build Complete!

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Transmitter Power Output

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First Contact

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WSPR Test

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QLG3 GPS Module

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Self Diagnostics

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QMX+ IQ to NaP3 - CW

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QMX+ IQ to NaP3 - SSB

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References

  1. QRP-Labs QMX+ https://www.qrp-labs.com/qmxp.html
  2. RSGB Tonight@8 - QMX+ Multimode 160-6m transceiver kit design and features by Hans Summers, G0UPL https://www.youtube.com/watch?v=6FheeAv3src
  3. Building the new QMX+ 12 Band QRP Transceiver by ‪@QRPLabs‬ https://www.youtube.com/watch?v=1Vpn-krqR8E

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Questions?

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Thank you!

Carol Milazzo, KP4MD

email: kp4md@arrl.net