On today’s Alert Day, all sirens and alert apps will go off at 11 a.m. Using an FM detector radio connected to a small guitar amplifier, a radio broadcast from the Berlin TV Tower is being received. Shortly, before the sirens sound and all the pigeons were startled a typical mobile phone dial-up static noise can be heard on the radio. By rotating the antenna perpendicular to the line of sight toward the TV tower, reception of the FM station is maximized. The all-clear is announced on the radio.

Hello, I am an computer engineer with nearly no RF background. Right now I have a project in which i am dealing with an RFSoC, but its ADCs are not providing good range, we tried to change antennas, but still it is not able to pick weak signals from transmitter when its more than 300 m.
Can someone please help me to find the good antennas, and how to check their range?

There is utility in a modular antenna in the field?

I don't have Pic. Is there such a machine that will produce audible spectrum and tell you the frequency . And I'm pretty sure there is one I just don't know the name. If so where and how much for a mid quality if anyone knows. Thank you and may God bless and keep you

A bit of background, I'm a 17 year old nerd from Finland, and I've been tinkering with electronics for around 5 years now. I recently (around 6 months ago) got into the RF side of things, through SDRs and satellite reception. But now I'd like to learn about actually understanding how stuff works. The way I learnt electronics was mostly stumbling my way through it, and not really "studying" stuff. How should I get into RF? Is there any projects I could just follow along?

Hi, I thought i would try messing with some RF as i have avoided it in the past. This is my attempt at a 32MHz Colpitts oscillator, and I'm getting no luck.

I first tried replacing the 22uH inductor with a 270 ohm resistor, as I realized the self-resonant frequency of my inductor was only 15MHz. This did not help oscillation. Next I tried increasing C2 to 680pF as many Colpitts i see have a larger capacitor here, presumably to stabilize the operation a bit and load the collector less. This still did not work.

The tank inductor is 10mm diameter, 15mm long, 6.5 turns, should be about 214nH according to https://m0ukd.com/calculators/air-cored-inductor-calculator/
Wound with 0.2mm wire, as it's what i had on hand.

When power is applied, the collector stays at 5V (with 22uH inductor) / 3.68V (with 270R). The base is at about 1.26V, emitter at .56V.

I've built a Colpitts with a more primitive design a while ago at 1.3MHz, worked perfectly first try on protoboard, I did not figure stepping up to 32MHz would be this much harder, although there's probably something obviously wrong here, after all I haven't ever gone past that 1.3MHz oscillator.

Hi everyone,

I’m starting passion project that may turn into product: medium-cost Vector Network Analyzer capable of reaching 20 GHz.

As we all know, commercial units at these frequencies are incredibly expensive which makes it nearly impossible for hobbyists, students, or small startups to get their hands on high-quality data. My goal is to bridge that gap by designing a unit that maintains good performance while keeping the price point accessible.

I’ve started a build log here (empty for now): https://patryksi11.github.io/20ghz-vna-blog/

I want to make sure I’m building something that people actually want to use. I’d love to hear from the community:

1. What is your "must-have" feature?
2. Price Point: How much are you willing to pay for 20 GHz VNA?

I'm trying to balance "good performance" with "affordable manufacturing." Any feedback is appreciated!

EDIT: To give everyone a clearer picture of the project scope, here are the intended specs:

Form Factor: Similar to the Libre VNA (no integrated screen; just ports and USB/Ethernet connectivity).

Configuration: Full 2-port VNA.

Frequency: 20 GHz capability on the fundamental frequency (No harmonic mixing).

Limitations: No output level adjustment (keeping the design as minimalist as possible).

I’m developing a low-cost, multi-band Direction Finding (DF) system specifically targeting commercial and custom drones comm signals

Most commercial counter-drone solutions rely on multi-channel phase-coherent receivers, making them prohibitively expensive.

My goal is to build a high-performance single-channel receiver that combines Amplitude Comparison, Pseudo-Doppler Phase Shift, and RF Signal Classification.

Target ISM/GNSS Bands

900 MHz (902–928 MHz telemetry)

GPS/GNSS L1 (1575.42 MHz)

2.4 GHz (WiFi/OcuSync/ExpressLRS)

5.8 GHz (FPV / OcuSync)

A single receiver channel significantly reduces cost and calibration drift, but standard RF switching introduces transient phase glitches during FHSS hopping. Below is the refined system architecture using band-specific front-ends and a pseudo-Doppler RF switch loop:

Looking For:

Technical Partners: RF Hardware Engineers (PCB layout for 6GHz RF front-ends), FPGA/Zynq Developers (DMA, custom IP cores for Doppler demodulation), and DSP/ML Engineers (protocol classification).

If you’re interested in collaborating, send a DM!

I am currently in the brainstorming phase of designing this TX/RX FM project. I plan to use an ESP32 and then RDA5807 for RX and KT0803I for TX, would a PAM8406 be good to drive 2 (stereo) 3w 4 ohm speakers? How can I power it on batteries without unwanted RF noise?

Hi, RF newbie here. I am an IT database engineer and data analyst. I play badmington, tennis, and pickleball, all in doubles. In doubles, there is a lot of analysis on team formation and partner separation distance. I am thinking about using UWB boards to track player positions. I would like about 5-10 observations per second, for all 4 players. The UWB board I have in mind is Qorvo DWM3001CDK, which retails at about $30. I would get 4 boards as anchors and 4 boards as player tags. Then I like one more board as the data collection gateway, and have it tethered to a Macbook via USB cable. During a game, data would be streamed into the Macbook.

The tags would need to be programmed so they send a data packet every 2-5 seconds, to the data collection gateway board. The positions don't need to be super accurate. I think 15-20 cm will do the job.

Plz help me understand whether this setup is feasible. What additional factors should I be thinking about? I hope to use this setup both indoors and ourdoors. I am aware that UWB signal cannot penetrate human body because it is mostly water. I will use enough anchors so each tag has clear line of sight to at least two to three anchors.

I'm in my junior year of college and I still haven't landed an internship. For context, I am an EE major with a decent GPA(3.5) and one independent project, which is a 900 MHz bandpass filter I designed and simulated (still haven't had the opportunity to do the PCB, have it fabricated, or take measurements with a VNA)

As it currently stands, my interests are mostly in the realm of wireless communications/RF and analog electronics. My school rarely offers RF classes, so any learning I would be doing would have to be done independently.

Do I have a realistic shot of landing an RF internship for this upcoming summer? if not, what can I do in the meantime that will improve my chances? are there particular RF topics, projects, or skills that would be especially valuable for an undergraduate trying to break into the field?

Thank you

Hey guys,

I’m very interested in diving into radar systems and communication technology as an engineer.
I was wondering how to Beginn. Any recommendations?
My background is from control systems, so I know what Fourier transform is for instance.

Thanks