NJ6N’s Amateur Radio & Electronics Blog

  • Inexpensive SvxLink Node

    Inexpensive SvxLink Node

    I wanted to build the most inexpensive SvxLink “node” or “station” I could using off-the-shelf parts. I bought an inexpensive BaoFeng “S9Plus” (it says “UV-S9X3” on the side) radio on Amazon for $28. For the computer system, I used a Raspberry Pi 4 that I already had, however, I also found a Raspberry Pi B+…

  • A 19″ rack rail case for Masters Communications RA-xx Radio Adapters

    A 19″ rack rail case for Masters Communications RA-xx Radio Adapters

    We’ve got a couple of these interfaces installed at our repeater sites and one is also providing a remote SvxLink/EchoLink node for our Santiago Site via link radios. There are already 3D printed cases available for these adapters but none that I’ve seen have any mounting tabs. I designed a case that has a row…

  • Fun with the “ECM” motor in my Forced Air Unit

    Fun with the “ECM” motor in my Forced Air Unit

    In 2009, I had my furnace replaced with a new high efficiency furnace with air conditioning by a local HVAC contractor. In 2011, I noticed the smell of smoke through the registers. Shortly after that, I noticed the compressor was still running while there was no air coming out of the registers! I called the…

  • Full Duplex Repeater Linking

    Full Duplex Repeater Linking

    Many years ago, SOARA Repeater and Technical folk fabricated 19″ rack shelves that contained Motorola Mitrec radios that were modified for full duplex operation. The shelves were fitted with “flat pack” band reject duplexers and hardline to interconnect them to the radios. The UHF linking band was monitored for some time using an Icom PCR-1000…

  • More Fun with 3D Printing

    More Fun with 3D Printing

    I continue to be amazed at how much you can do with 3D printing technology. When I need an enclosure for something, it’s really nice to be able to design the perfect fit for my project. When a part breaks, I can often design and print a 3D part to replace it. 3D printing is…

  • Hendricks BITX20A SSB Transceiver Kit

    Hendricks BITX20A SSB Transceiver Kit

    Many years ago, circa 2007, I bought a Hendricks Bitx 20A, 20 meter QRP SSB transceiver kit at the Pacifcon conference in San Ramon, CA. I bought the main kit along with the machined and painted Ten Tec case and KD1JV digital frequency display kit. I figured I would build it over a holiday break…

  • Ultimate 3 WSPR/QRSS Transmitter

    Ultimate 3 WSPR/QRSS Transmitter

    Way back in 2016 I purchased a QRP multi-protocol transmitter kit from QRP Labs (https://qrp-labs.com). I believe my thinking was that SOARA could use this to replace the clubs K6LLL memorial 10 meter beacon at Temple Hill. The current K6LLL beacon consists of a BASIC Stamp microcontroller that generates the keying for a Radio Shack…

  • PowerPole Distribution Box

    PowerPole Distribution Box

    I’ve designed and built several different Anderson PowerPole distribution boxes over the years. Recently I found a design by KM6RW on Thingiverse for a “Decora” style PowerPole distribution panel that fits into a standard electrical outlet box. It can be installed in the wall or on the surface. I sliced the STL using Cura and…

  • Building an svxLink station

    Building an svxLink station

    Components Preparation Installing & Configuring svxLink pi@raspberrypi:~$ aplay -l **** List of PLAYBACK Hardware Devices ****card 0: seeed2micvoicec [seeed-2mic-voicecard], device 0: bcm2835-i2s-wm8960-hifi wm8960-hifi-0 [bcm2835-i2s-wm8960-hifi wm8960-hifi-0]Subdevices: 1/1Subdevice #0: subdevice # pi@raspberrypi:~ $ arecord -L…sysdefault:CARD=seeed2micvoicec…hw:CARD=seeed2micvoicec,DEV=0

  • MultiMode Digital/Analog Repeater

    MultiMode Digital/Analog Repeater

    Recently, I built a full duplex repeater that supports FM, Yaesu System Fusion, DMR, and D-STAR all on one frequency pair. Like many SOARA members, I use an MMDVM hot spot for digital modes. My new repeater is essentially a full duplex hot spot using a MMDVM (multi mode digital voice modem) board as the…

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