NJ6N’s Amateur Radio & Electronics Blog
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Automatic Power Off
I have used an APO-3 automatic power off unit in my vehicles for many years. I recently needed to add a second one for my rear-facing dash camera in my truck and wondered what it would take to design and build one myself. I decided to use an Arduino Nano as the microcontroller since I…
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3D Printed Dipole Support
for portable or fixed use I had some left over aluminum tubing from other antenna projects and thought it would be useful to build a 10 meter dipole out of it. I needed a way to attach the elements to a block of wood and attach the block of wood to a TV antenna mast.…
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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…
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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…
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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…
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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…
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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…
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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…
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Using a TNC to send an APRS Beacon
It’s SOARAs 50th Anniversary and I wanted to send out a Beacon on APRS to let folks know about our special operating event at Gilleran Park in Mission Viejo on May 18th and 19th, 2024. There are many ways to do this and I chose to use a Kantronics KPC3+ TNC and handie-talkie. Most TNCs…
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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…
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