Category: Electronics

  • Code Practice Oscillator

    Code Practice Oscillator

    My Brother Dana, K6NR, needed a CW oscillator for an upcoming presentation on Morse Code. I didn’t have a code practice oscillator, but I have plenty of PARTS! So I set out to build one. I Googled for Code Practice Oscillator Schematics to get some ideas and found this design. It’s a clever project that…

  • More MMDVM hot spots

    More MMDVM hot spots

    I needed to replace a broken hot spot case recently. At first, I reprinted my original ugly square ZumSpot + Nextion design from years ago. I was happy to be able to print it using ABS with my new printer. But I got to thinking how my newer design, a rechargeable ZumSpot+Nextion Hot Spot could…

  • QRP Labs QDX 5-band Digital Transceiver

    QRP Labs QDX 5-band Digital Transceiver

    Way back in April of 2023 I bought a QDX digital transceiver from QRP Labs. QRX stands for “Qrp-Labs Digital Xcvr”. I thought it would be fun to take with me on trips. I finally got around to building it in August, 2024. The instructions are very good with excellent diagrams and illustrations on how…

  • Tait T855 Rx & T856 Tx module setup

    Tait T855 Rx & T856 Tx module setup

    Our high-level 440 and 220 repeaters on Santiago peak use modular rack-mounted Tait radios. Our 440 band repeater uses a T855-20 series 1 module for receive and a T856-20 module for transmit. The transmitter is capable of 25 watts or better, but we have configured it for 10 watts output to drive an external TPL…

  • Digital Voltmeter/ Ammeter

    Digital Voltmeter/ Ammeter

    I found some small, inexpensive digital voltmeter/ammeter panel displays recently and thought it would be nice to have an inexpensive inline meter that I could use to measure various devices. I designed a case and by version 3, I think I’ve got a nice little gadget. The connectors on the back of the meter module…

  • External PL control for VXR-5000V/RLC Club Repeater

    External PL control for VXR-5000V/RLC Club Repeater

    A few years ago, I upgraded SOARAs primary VHF repeater at our Temple Hill site to a “new to us” Yaesu/Vertex VXR-5000R repeater. The new VXR-5000V repeater features an internal CTCSS decoder and encoder and a basic repeater controller. Around the same time, I replaced the half-duplex GM-380 link radio with a pair of Motorola…

  • All-In-One-Cable Interface with svxLink

    All-In-One-Cable Interface with svxLink

    I recently saw a video by Hayden, VK7HH on his Ham Radio DX Youtube channel about a new “All In One Cable” (AIOC) computer <=> radio interface. I found a HackADay article about it that was very interesting as well. The AIOC is an STM32 based microcontroller that emulates a sound card and provides a…

  • Kenwood RC-D710

    Kenwood RC-D710

    A long time ago, 2009 or so, Ham Radio Outlet was offering the RC-D710 control head and TNC for a very reasonable price. This is the identical control head used on the Kenwood TM-D710 mobile transceiver. It includes a built-in Terminal Node Controller (TNC) and APRS software. I bought one thinking I could use it…

  • Fun with Meshtastic®

    Fun with Meshtastic®

    “Meshtastic® is a project that enables you to use inexpensive LoRa radios as a long range off-grid communication platform in areas without existing or reliable communications infrastructure. This project is 100% community driven and open source!” I’m not sure where I first heard about this new technology called LoRa or “Long Range” and Meshtastic but…

  • mini USB Power Box

    mini USB Power Box

    portable USB power from 12VDC Recently, my brother told me about a problem he had with a USB power adapter that was causing a lot of RFI on VHF in his mobile setup. It’s not hard to imagine how inexpensive 12V to USB adapters could cut corners and cause interference. I found some higher quality…