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  1. Receiving the HamSci WWV Scientific Test Signal

    I was perusing the latest edition of QST and noticed a short article on some scientific experiments that hams were doing with WWV and WWVH. I tune in to WWV occasionally to check propogation, and also for frequency calibration of my Kenwood TS-2000.

    April 2022 QST article on WWV science

    Wow, this seems cool! The HamSCI WWV webpage has a bunch of information, including a great presentation by Kristina Collins KD8OXT.

    Receiving the Signal

    I recently added a KiwiSDR at my home station, so I twisted the dial over to WWV (in software, pretty anticlimactic), and started listening. I barely heard the test signal from Hawaii because propagation that evening was very poor. There was several solar flares over the next few days, causing lots of interference ...

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  2. Simultaneous Multi-Band WSPR Decoding with KiwiSDR and WsprDaemon

    I've been interested in receiving Weak Signal Propagation Reporting (WSPR) signals recently, for two reasons. The first is that the picoballoons that we launch use WSPR for position information. Not only do I directly receive the picoballoons after we launch them, but I also use the WSPR network to check on their location around the world. I don't have a receiver in Europe, so I rely on other amateur radio operators to receive the balloon and post its location online, and I want to give back to the network.

    The second reason is that I'm curious about how far I can receive signals with my somewhat compromised city antenna. While my fan/parallel dipole antenna will never perform as well ...

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  3. Building a Multi-band Fan/Parallel Dipole Antenna

    Now that Solar Cycle 25 is upon us, I wanted to get active on the HF bands. My primary bands of interest are 40 and 20 meters, so I wanted to build a multi-band antenna for these frequencies. After some research, and wanting only one antenna connection for my Kenwood TS-2000 radio, I settled on a fan/parallel dipole antenna. It's very simple to build, and really hard to beat the performance of resonant dipoles.

    Choke Balun

    A balun is required when you are interfacing a BALanced device, such as a dipole antenna, to an UNbalanced device, such as a coaxial cable. Coaxial cables are unbalanced because from an RF perspective, there are actually 3 conductors in a ...

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  4. Kenwood TS-2000 Frequency Calibration

    I've been spending a lot of time recently listening to WSPR beacons. The recent picoballoons that I have launched all used WSPR for to transmit their location and altitude. WSPR is a great for solar-powered picoballoons because the transmit power is on the order of 10 dBm (10 milliwatts), which is extremely low.

    One night, I was just passively watching the WSPR decodes while doing other things on my shack computer. Every once in a while, I would notice a WSPR beacon that was outside of the 200 Hz WSPR band, and therefore wasn't decoded by WSJT-X. I thought this was interesting, who was transmitting out of the band? The transmissions seemed to always be on the high side.

    This ...

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