NJ6N’s Amateur Radio & Electronics Blog
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LED S-Meter for /\/\otorola
I have been using Motorola CDM-750/1250/1550 radios to build digital and analog repeaters, full duplex links, and digital hotspots for some time. Quite a few of the radios I have do not have a front panel display. However, they do have a 16 pin accessory jack that has all of the usual signals including TX/RX…
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Dire Wolf & YAAC for APRS
I had an old Icom ID-880H lying around. The ID-880H has something many radios lack, a Data port! That gave me an excuse to buy another Masters Communications Radio Adapter kit! The DRA-50 is very similar to the RA-35/RA-42 interfaces that I’ve used before. The DRA series of adapters are designed to be used in…
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K3NG Electronic Keyer
Recently, someone mentioned they were looking for a code practice keyer during one of our HF nets. I have a few older keyers in my collection including a CMOS keyer that I built from a QST article back in the early 80’s or so and a Logikey K-1. I had recently built a very simplistic…
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Quansheng UV-K5
I have been a fan of the firmware modified Quansheng UV-K5 handhelds for a while now. The base radio is not bad and the features added by Hams through firmware modifications have been very useful. The radio is available through the usual sources including AliExpress, Amazon, Ebay, etc. The radio is known as the Quansheng…
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Malahit/N7DDC ATU-100 EXT Antenna Tuner
This is a 100 watt HF/6m Antenna Tuner kit sold through the usual consumer sites like Amazon, Ebay, and AliExpress. It was apparently designed by N7DDC. I happened to run across this tuner kit while looking for something else on Amazon. At $30 or so, it was cheap enough to take a chance on and…
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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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