Mostly ham radio, electronics, programming, microprocessors, radiation and (radio) astronomy
Spain
Joined December 2013
- Tweets1.4K
- Following179
- Followers1.2K
- Likes3.9K
Miguel A. Vallejo retweeted
Testing 15 Euros ESP32 : 80Mhz wide spectrum on 2.4Ghz with recent hack : here is DATV and wifi. Next step : getting I/Q and having TX ! A new horizon for cheap sdr : eSpDR.
Miguel A. Vallejo retweeted
Haciendo pruebas para el #eclipse he cazado un avión pasando justo por delante del Sol 😎 A las 21:04 CEST desde #boecillo #valladolid
Miguel A. Vallejo retweeted
Extracts information from radio signals via SDR devices
github.com/BatchDrake/SigDig…
Miguel A. Vallejo retweeted
23cm band Restrictions in Europe from December 27, 2025
amsat-uk.org/2025/07/20/23cm… #amsat #hamradio #hamr
Miguel A. Vallejo retweeted
Here's the Arduino sketch for the amateur radio beacon using the SX1262. It works on RAKwireless RAK4630/RAK4631 boards, currently used on the RAK WisMesh Board ONE. Output power is ~8dBm at 1296 MHz and ~20dBm at 903 MHz. The code supports 144-1300 MHz, but matching components and filtering need tweaking. github.com/ibelinp/Amateur_R…
Miguel A. Vallejo retweeted
We used the historic Dwingeloo telescope to bounce a signal off the surface of Venus, and receive its echo! This marks only the second time that amateurs have achieved an 'EVE' (Earth-Venus-Earth) bounce. Venus was about 40 million kilometers from Earth.
camras.nl/en/blog/2025/first…
ALT Graphs showing EVE detections: 5.4 sigma for Dwingeloo-Dwingeloo, 8.5 sigma for Dwingeloo-Stockert, 9.2 sigma for combined Dwingeloo/Stockert
Miguel A. Vallejo retweeted
My article on using smartphones to study the ionosphere is now out in @Nature. @UiTNorgesarktis @Google @ucboulder rdcu.be/dZ7lP Also take a look at the Smith et al. article that I am discussing: nature.com/articles/s41586-0…
Miguel A. Vallejo retweeted
6100km TEP contact on the 144 MHz band between Spain and St Helena - 25th Sept 2024... ei7gl.blogspot.com/2024/09/6…
Miguel A. Vallejo retweeted
Una pequeña y muy portátil sesión de #astrofotografia desde la sierra de la culebra en #Zamora. Sacadas con una vieja Sony A77 y un aun mas viejo CJZ135 a F4. Cada imagen tiene unos 20 minutos de exposicion. Objetos de sobra conocidos M31 y a M45 😅.
Miguel A. Vallejo retweeted
No puede fallar... irse de vacaciones y superar los 300km en LoRa APRS.
IM97PR > JM19LM / Murcia > Mallorca
#lora #loraaprs #loraaprstracker #hamradio #hamradioamateur #radioaficionado #radioaficionados
Miguel A. Vallejo retweeted
FTX-1F does not support full-duplex communication. I was told this directly by Yaesu staff at the Tokyo Ham Fair. Pity.
Miguel A. Vallejo retweeted
Just learned that WSJT-X, an open source ham radio app, now requires a keycode to use some particular mode. This is contrary to all principles of open source (freedom to use the software) and ham radio (experimentation and learning).
Part 2 of VK3FUR's analysis of the new WSJT-X SuperFox Verification system: sprocketfox.io/xssfox/2024/0…
Miguel A. Vallejo retweeted
Periodic but friendly reminder to remove the batteries from old electronics.
Miguel A. Vallejo retweeted
"Give someone a Cortex-M4, and it'll be too cumbersome to implement cool hacks. But give someone a grain of rice that was tricked into doing computation at a few MHz? They'll bitbang USB and USB-PD on it." - @Spirit532_
Miguel A. Vallejo retweeted
New post on downloading and installing "free" Intel/Altera version of the excellent ModelSim Questa VHDL+Verilog simulator. I've been using this simulator professionally for 30 years now and it's great to have it up and running at home for hobby projects.
blackmesalabs.wordpress.com/…
