Колпино, Санкт-Петербург | Kolpino, St. Petersburg, 2016.
(c) Artem Lezhepekov
#closeuprussia #artemlezhepekov #rf #photography #photo
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OK fedi, I get it. #Meshtastic sucks and uses proprietary #LoRa chips. So #LoRaWAN is out to.
So what should I be using if I want to set up some battery-powered sensors in the forest around the house. What open #LPWAN stacks are there that would work on 1 to 2 km scale in hilly terrain? #Wize ? #Weightless ? #DASH7 ? So many protocols... Help!
Oh, it can get as cold as -30°C here, so that's a factor as well.
Anyone know offhand, if an FM radio station is broadcasting from a hilltop to the northeast, how should I orient a standard cheap floppy wire dipole for best reception?
Assuming the antenna long axis is vertical, should the arms of the “T" be perpendicular to northeast?
Also, how could I couple a dipole to a clock radio with a short single wire antenna and no antenna terminals?
Soup-to-nuts investigation and implementation.
"A hybrid wireless communication system for real-time image transmission is demonstrated to show the outstanding features of SLMPM. We believe that SLMPM can contribute to the sustainable advancement of future wireless communications, rendering them more cost-effective, energy-efficient, environment-friendly, and ubiquitous."
Pre-xenophobic Larry Niven stuff, except real.
NatureSolar-powered light-modulated microwave programmable metasurface for sustainable wireless communications - Nature CommunicationsAchieving sustainability in wireless communications is crucial yet poses significant challenges. To address this, the authors propose and demonstrate a solar-powered programmable metasurface enabling hybrid light-to-microwave wireless communications.
Today I set up my three HP 5335A counters so I could measure the OCXO warmup curves of both the units that have OCXOs using the third, which has an external GPSDO reference. I wrote a PHP script to measure Frequency A and Frequency B alternately every 4 seconds, with A and B inputs connected to the Reference Out sockets of the other two. Here's how it looks on a garish Apple Numbers chart. Both oscillators seem to have a very similar warmup curve - though the frequency offset is slightly different (it's quite hard to calibrate them exactly) #radio #rf #electronics #HP
The results are in, with 18 votes. I kind of like bsky but not seeing a critical mass of people in my areas of interest.
If you answered other, please feel free to explain.
In honor of this landslide vote, here's a photo of my latest tinkering: making pipecap filters for an 11 GHz RF multiplier (using the W1GHZ board & design). I'll use brass M3 tuning screws once some arrive from McMaster-Carr, although I'd be interested to see if they are very different to stainless steel. And yes, I had to order them online after not finding any metric brass fasteners locally. Why not use SAE screws? Standard metric screws have much higher TPI, even more than fine-thread SAE. This will provide better mechanical stability & finer tuning, but then again, I'm not building a spaceship here, so
#hamradio #amateurradio #microwave #rf #nerds #fediverse
RE: https://social.kernel.org/objects/81c8273c-6a3f-43d9-bfc9-673541118280
If you answered other, please feel free to explain.
In honor of this landslide vote, here's a photo of my latest tinkering: making pipecap filters for an 11 GHz RF multiplier (using the W1GHZ board & design). I'll use brass M3 tuning screws once some arrive from McMaster-Carr, although I'd be interested to see if they are very different to stainless steel. And yes, I had to order them online after not finding any metric brass fasteners locally. Why not use SAE screws? Standard metric screws have much higher TPI, even more than fine-thread SAE. This will provide better mechanical stability & finer tuning, but then again, I'm not building a spaceship here, so
#hamradio #amateurradio #microwave #rf #nerds #fediverse
RE: https://social.kernel.org/objects/81c8273c-6a3f-43d9-bfc9-673541118280
I spent far too much time today trying to work out why my little ESP32C3 Supermini board was having trouble connecting to my WiFi. Turns out that the little ceramic antenna needs to be helped with a 62.5 mm long piece of wire.
For some reason this problem only made itself known when the device was right next to my WiFi router, but never showed up at all when it was on my desk on another floor. From another floor it worked every time. 10 cm away from the router it needs the extra antenna.
Dear radio frequency engineering fediverse,
Do you know of a good article that describes how to conduct a two-tone test to measure intermodulation properly? I understand the basics and I know to generate the test signal and how to measure the result on a TinySA. However, I don't know how to determine if my test signal is clean enough, has a reasonable power level, etc. In other words, I don't trust that I understand my test setup enough to trust my results..
Do you have any good links?
A day of learning #meshtastic and having good fun reading the stats, mqqt possibilities, and digital mapping, I'm just wondering if meshtastic is the #5g of #APRS
Still, getting an applied understanding of #radio #frequencies #rf is eye opening. Lots more to learn :)
Начиная с 24 февраля 2022 года на территории России проводятся масштабные испытания ядов на людях с целью изучения воздействия различных отравляющих веществ на организм человека и параллельного решения прочих задач, возложенных на российские спецслужбы.
Сайт: https://plors.org
Форум: https://forum.plors.org
Is it just me or is every demo/overview of the #FlipperZero extremely unimpressive (especially those for a mainstream audience).
I regretfully watched one such video earlier and one of the features highlighted was the ability to copy TV remote signals 
...I get it was aimed at a non-technical audience but I literally had a watch that could do that when I was a kid and to this day grandparents around the world have universal remotes with this capability...
So I want to put it out there to the #infosec community - where are the cool flipper zero #projects? And I don't mean installing #DOOM or some other quirky play thing. I want to see legit #RF #hacking, or at least using the #GPIO!
#askfedi #askinfosec #rfhacking #pentesttools #hackingtools
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@nixCraft counter measures like that are in fact necessary if you have a "mandatory ISP router" that cannot be trusted (on the WLAN side of things). Packing it in tin foil would be better, but the router would die from overheating. So a fine metal mesh all around would be a cheap and feasible solution. Maybe adding some ferrite beads to all the in- and outgoing cables to block any RF 'leaking' through cabeling/shielding. #RF #HD #WifiBLOCKER
the more you learn about radio and spend time listening to hams or unlicensed operators freebanding, the more you want to know. same impulse as when i started learning #AI.
speaking of, there's a GGUF model for `phi2-electrical-engineer` that will write code for collecting #TDOA data from a kiwiSDR which is nice cuz there isn't a ton of tooling i can find on analyzing or processing. tons of interest in AI for telecom but they're not showing their work yet.
SimNEC - I absolutely have to check this out this weekend: https://www.ae6ty.com/smith_charts/ #hamradio #electronics #antennas #rf
hey @ducksauz the fcc found a pirate in mt. pleasant #PVD:
In January 2025, the FCC investigated a complaint about an unlicensed broadcast on the FM dial at 97.1. The FCC sent a warning letter to the property owner.
In February 2024, the FCC issued a Notice of Illegal Pirate Radio Broadcasting (NIPRB) to Nerva Jean Philippe and Edith Jean Philippe, the landowners of the property.
- https://www.providencejournal.com/story/news/local/2025/01/28/fcc-investigates-unlicensed-pirate-radio-station-in-providence/77933130007/
- https://forums.radioreference.com/threads/alleged-providence-pirate-radio-station-tunes-into-trouble-with-the-fcc.484246/
The Providence Journal · Alleged Providence pirate radio station tunes into trouble with the FCC.
Weekend tinkering: finally made enough room for a microscope on my bench and looked at small things. The chip of interest is 0.7mm wide: a ~60 GHz amplifier.
#hamradio #amateurradio #electronics #rf #mmic #microwave #millimeterwave #mmwave
#hamradio #amateurradio #electronics #rf #mmic #microwave #millimeterwave #mmwave
Шальский, Республика Карелия| Shalsky, Republic of Karelia, 2013.
(c) Artem Lezhepekov
#closeuprussia #artemlezhepekov #rf #photography #photo
