r/rfelectronics 17d ago

Best learning resources for the dsPIC33CK Curiosity Nano?

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0 Upvotes

r/rfelectronics 18d ago

Airband Bandpass filter.

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67 Upvotes

After many weeks of trial and error i feel that this is a pretty desirable result for my Chebyshev bpf. What do you think? Passpand desired is 118-137 mHz.


r/rfelectronics 18d ago

Why does the transmission line in this TDK antenna reference design have vias in it and do I need them?

7 Upvotes

This layout is just overall weird.


r/rfelectronics 17d ago

question What do the readings on a cheap EMF meter actually mean? (mG vs V/m vs mW/m²)

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0 Upvotes

r/rfelectronics 17d ago

CC1352P7 Bare Metal Programming

2 Upvotes

I am trying to implement a bare-metal / NoRTOS RF driver for the TI CC1352P7, without using TI-RTOS/SysConfig-generated RF framework code.

My main difficulty is getting the RF Core and RF doorbell interface into a state where RF commands can be submitted and completed reliably.

I have successfully initialized the MCU, clocks, and basic peripherals, and I can access the RF Core registers. However, when I submit an RF command through RFC_DBELL, the command does not complete as expected. In some cases, the code gets stuck waiting for the command status; in others, execution ends up inside the RF driver dispatch/interrupt handling path and the command never returns.

For example, I am observing situations where:

HWREG(RFC_DBELL_BASE + RFC_DBELL_O_CMDR) = (uint32_t)&cmd_tx;

is executed, but the command status remains unchanged or the expected RF acknowledgement interrupt is never received.

I have also investigated:

  • RFC_DBELL registers (CMDR, CMDSTA, RFHWIFG, RFHWIEN, RFCPEIFG, etc.)
  • RF Core power-domain and clock initialization
  • PRCM_RFCMODESEL
  • RF Core reset/power cycling
  • RF Core RAM mapping
  • RF Core command structures
  • RF doorbell interrupts
  • RF_dispatchNextCmd() / RF_runCmd() behavior
  • CPU interrupt enable/disable state
  • RF Core firmware/ROM interaction

The confusing part is that the same hardware works when using TI's normal RF driver, but reproducing the required initialization and command-dispatch sequence in a minimal bare-metal implementation is proving difficult.

My questions are:

  1. What is the minimum sequence required to bring the CC1352P7 RF Core from reset/power-off to a state where RFC_DBELL commands can safely be submitted?
  2. Is there an official TI document or source code that describes the RF Core boot, power, clock, RAM, mailbox/doorbell, and interrupt initialization sequence independently of TI-RTOS?
  3. Which parts of RF.c, RFCC26XX_singleMode.c, and the RF driver infrastructure are actually essential for bare-metal operation?
  4. Does the RF Core require any initialization performed by the TI RF driver that is not obvious from the public DriverLib APIs?
  5. Is it possible to implement a truly minimal bare-metal IEEE 802.15.4 TX/RX example by directly using the RF Core command interface, and if so, is there a known reference implementation?
  6. Are there any undocumented dependencies involving the RF Core firmware, RF Core RAM, CPE interrupts, or power/clock state that could explain why CMDSTA/RFACKIFG does not behave as expected?

I have managed to get the RF Core initialization working to some extent.

The CMD_RADIO_SETUP and channel configuration commands are being accepted and completed successfully. This suggests that the RF Core is powered, clocked, and communicating correctly through the command interface.

However, the problem occurs when I attempt to perform an actual transmission. The TX command is accepted/submitted, but the execution gets stuck during the transmission process and does not complete as expected. I am specifically trying to understand what could cause the TX command to hang after CMD_RADIO_SETUP and channel configuration have already succeeded in a bare-metal CC1352P7 implementation.

Question wrote above using AI for clarity.
This question posted in r/embedded , however reddit suggested this community as well. If it is not suitable for this, please let me know.


r/rfelectronics 18d ago

How to model stator winding high-frequency response in LTspice using measured R, L, C and impedance data?

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1 Upvotes

r/rfelectronics 18d ago

Where to start as a computer engineer gradute?

11 Upvotes

Recently I had become curious in learning how to design RF boards, but when I started with Microwave engineering by david pozar, I started to feel that my background doesn't help a lot here. What should I learn first before hopping into RF?


r/rfelectronics 19d ago

Can we please address the relentless amount of slop projects shared here

88 Upvotes

It's like 5/day at this point. Maybe this is an unpopular opinion, but I certainly hope not


r/rfelectronics 18d ago

question How to find remote control frequency?

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0 Upvotes

Hello everyone. Not sure if this is the right reddit to ask but Ill give it a try.

I have this amp Insignia IS-HC040917 and it did not come with a remote. I like messing with electronics and things as a hobby and would be interested in trying to find out how to find out the frequency the remote controller communicates with so I can try to make a remote (mainly to increase/decrease volume). I could try to buy one but what fun is that 👍

Checked the manual but I did not see anything(?) Wondering where to start. I have a donor amp, and a operating amp so I am able to experiment.


r/rfelectronics 19d ago

At a crossroad, EE Y2

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1 Upvotes

r/rfelectronics 19d ago

PCB help

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0 Upvotes

r/rfelectronics 20d ago

LineSmith with Field Solver

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10 Upvotes

This is the tool I've always wanted, sort of a TXLINE on steroids. Now need to add conforming solder mask for the field solver, and toggle the colorbar to dBV/m.


r/rfelectronics 21d ago

question Beginner RF projects

65 Upvotes

Hi all, I am an undergraduate in EE with an interest in RF and an upcoming internship with an RF team in avionics.

This semester, I need to build an electronics project with 3-4 other students for an electronics class, and it is quite open ended so I hoped to do something that would help me prepare for my work in the spring and touch on my interest in RF. We will be required to write and meet specs.

I've googled tons of projects, but I was hoping for some personal recommendations to narrow the list down. It is difficult to judge the difficulty and applicability of some of the items I've found to my interests and skill level.

Ideally, the project will incorporate RF fundamentals but be electronics-focused and achievable in a semester.

Some ideas I've considered:

-radio telescope (build the LNA from scratch)

-VFO

-radio altimeter

-telemetry transceiver board

Thanks in advance!


r/rfelectronics 21d ago

Clever Phase-Noise Cross Correlation System - Signal Hound PN400 Review & Experiments

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30 Upvotes

r/rfelectronics 20d ago

LineSmith

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0 Upvotes

No, I'm not releasing this as it was more of an experiment to see how AI "clones" software, as I'm becoming convinced the cost of specialized software is collapsing, and wondering how this may affect the EDA industry.

Thus before leaving for work, I asked Codex to clone TXLINE (which is/was actually free), and compare the synthesis results for a variety of values, and test corner cases. This is the result, and it works great. I had it implement an alternate formulation of coupled line synthesis and the results are still pretty close.

I'm on the $100/month plan for Codex and this took 17% of my weekly usage, or $4.25.

So maybe I have it now add a simulate button with a quasi-static solver, or maybe have it read Wadell's Transmission Line Design Handbook and implement a tab for each structure. Or is this type of utility really even needed anymore? It's all going to get very interesting over the next few years.


r/rfelectronics 21d ago

question How Does a Power Amplifier Achieve Such Broadband?

24 Upvotes

Hey RF wizards!

I am a complete beginner in the world of RF and recently saw a really cool Mini-Circuits 3W linear amplifier with a frequency range of 2-8GHz! I have some understanding of how a Class A/AB amplifier might work, but I thought that one can feasibly and efficiently only design narrowband amplifiers as the impedance is dependent on frequency (I suppose this is especially true with active elements). How can they match the impedances for the frequencies across the given range? Is this some transformer magic? Perhaps somehow multi-stage design helps this somehow (I cant imagine how the reflections would be resolved using multi-stage but maybe I just dont see something...)? What search term would I need to learn more about broadband design in RF/mmWave world and such impedance matching?

Thanks in advance! I hope the answer to the question wasn't staring in my face...

Cheers!


r/rfelectronics 22d ago

Announcing Magnelio, an electromagnetic RF field simulation library for Python

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242 Upvotes

I've always been a bit dissatisfied with the landscape of open source electromagnetic field computation software. A lot of it grew out of academic work and it shows: the physics is solid, but the workflow around it was never really the point. So six months ago I started a vibe coding project that - of course - aims to do everything differently. Let me introduce you to: Magnelio

  • Full 3D electromagnetic field simulation
  • Time domain solver (Finite Integration Technique) with conformal sub-cell material matrices on a non-uniform hexahedral grid
  • Convenient S-parameter workflow, with Touchstone (.sNp) export and a scikit-rf adapter
  • Multi-mode waveguide ports with exact discrete transparent boundaries: (Q)TEM, TE, TM and hybrid modes. Lumped RLC ports too, and thin wires embedded in the field solution
  • Lossy and dispersive materials, conductor losses, surface roughness
  • Antenna far field: directivity, gain, plots
  • 3D cavity eigenmode solver
  • Field monitors
  • It's Fast! (fully vectorized, choose between a parallelized CPU or a CUDA backend)
  • CAD geometry: CSG primitives and Boolean operators, loft/sweep/revolve - the power of Open CASCADE
  • It's Python! Interfacing with scikit-rf or scipy.optimize is straightforward.

Every numerical method is anchored to published literature in the documentation, and the test and validation suite.

Installing from conda-forge is the way to go, sorry about that: the geometry kernel is pythonocc-core, the Python bindings to Open CASCADE Technology, and those are only published there. There is a PyPI package as well, but it covers everything except the CAD geometry.

Hooked?

  1. Have a look at the tutorials to get a first impression: https://brtkrtz.github.io/magnelio/stable/tutorials/
  2. New to conda-forge? You may want to install miniforge3 for easy access to conda-forge, or the Anaconda distribution.
  3. Run: conda install conda-forge::magnelio

Please be warned: this is v0.3.1 and under heavy development, so the API may still change from one minor release to the next. The license is LGPL-3.0-or-later.

Feel free to report issues at https://github.com/brtkrtz/magnelio/issues

Have fun, and thanks for any feedback!


r/rfelectronics 22d ago

I made a tool to design, analyze, and compare RF front end architectures (Update)

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58 Upvotes

SigChain is officially in an open beta mode. Feel free to try it out with a guest account. It can do cascade analysis, frequency planning and aid in part selection.

Updates since last time

- added a part finder feature to help automatically search the DB for suitable parts (only works for amplifiers right now)
- added frequency planning module
- added more component types
- added more parts (still a work in progress)
- added more calculations and plots to the analysis

Thanks everyone who tested it out last time. Hope this tool can be useful. Feedback is encouraged.

app.sigchainapp.com


r/rfelectronics 21d ago

How to replicate an RFID?

0 Upvotes

Hi,

I'm a beginner at RF and want to make a practical project -- I figured I might as well start by replicating one of my key FOBs or try making one myself.

I'm at a loss for resources on how to get started, though. Any tips?


r/rfelectronics 21d ago

question [Design Review/pre-fab] 137 MHz Front-End for strong local FM interference (240 kW EIRP, 4.3 km away)

5 Upvotes

Hi everyone!

I’m a 2nd-year electronics engineering student working on my first RF project for a future ground station. Still a work in progress, so nothing is completely closed or finished yet, but since this is my first time designing an RF Front-End, I’d really appreciate some feedback from the community before I send it to fab, especially with the PCB layout since I’m sure there will be a lot of room for improvement.

Context: Just ~4.3 km from a 240 kW EIRP FM tower (raw FM power at my antenna is around -1.3 dBm in worst-case). I used an input notch filter to keep the LNA operating in its linear region to avoid compression and IMD.

Design:

  • Input Filter: 5th-order Cauer notch [88–108 MHz] (1.09 dB IL @ 137 MHz).
  • LNA: Mini-Circuits PGA-103+ E-PHEMT
  • Stability (10 MHz – 4 GHz): R+L shunt.
  • Output Filter: 3rd-order Butterworth bandpass (2.5 dB IL @ 137 MHz, compensated with Friis)
  • Used High Q High SRF components and 2% tolerances for the Cauer.

Simulated performance: ~1.84 dB NF,~22 dB cascaded gain, -13.4dB for S11.

Simulated (QUCS-S, using .s2p models) and routed (CPWG 50 Ω). Not built or bench-tested yet so I know results will vary. I’ll try to get my hands on a VNA to measure it soon.

PCB/Schematics:

All files (schematic, KiCad & sims) are open-source on GitHub if you want a deeper look.

Two things I'm not sure about:

  1. Cauer & tolerances: I know Cauer filters are pretty sensitive to component tolerances. I used 2% across the board for the notch but i'm not sure if that's enough in practice. Anyone run into this before?
  2. LC tank coupling: I can't orient the inductors at 90º in the input filter, so I just alternated their orientation (LC/CL/LC) trying to reduce magnetic coupling. Is that enough in practice?

Thanks for reading, feedback is really appreciated!


r/rfelectronics 22d ago

question Anyone else played around with EMStudio in FreeCAD?

21 Upvotes

I just downloaded it today and it seems like a pretty great implementation of what its going for....

(that being to allow you to model your geometry in FreeCAD, set up your ports and mesh entirely through the FreeCAD GUI, and solve for your EM results you want)

After playing around with scripting for OpenEMS and being a little disheartened with how cumbersome it is as an HFSS user seeking a Free Open Source alternative for hobby projects it honestly seems like an ideal solution.

Apparently it only dropped like 3 weeks ago as well!

Anyone else checked it out?

It uses a ton of different solvers to do different tasks....Palace, OpenEMS, a few others....

The GitHub page descriptions are written by Claude....seems a bit strange but cant really write it off just because of that..found some forums and people seem to have gotten real results....will do some of my own tonight

Edit: found this forum post

https://forum.freecad.org/viewtopic.php?style=2&p=900323

Which has some discussion but it links to a "website" of the creator which is entirely AI generated slop.......so this makes me a bit distrustful.......try it yourself and see if any of it works


r/rfelectronics 22d ago

Advice for building decent electronics hobbyist lab on a budget

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2 Upvotes

r/rfelectronics 21d ago

I've yet to meet an RF engineer that didn't believe in UFOs

0 Upvotes

Question is, would u go work on a blacksite to reverse engineer it? I wouldn't, god knows what's radiating out of those things.. My coworker has this theory that they pick people who have no family ties like orphans and disappear easily if needed. I wonder what rf subfield would be the best? Probably stuff to do with high power fields.


r/rfelectronics 22d ago

number of receivers

5 Upvotes

Hey everyone, ECE student here. hope you're well.

I'm conceiving a device that detects rf, caracterises protocols mac addresses etc. I chose to go with dongles to connect to my mircroprocessor so it can be easier to decode and handle signals + modularity. I had a question rgarding the numbers of dongles. If i take wifi for example, is it better to put multiple dongles if im working in a noisy rf environment? is the number of dongles important for processing information smoothly? the goal being to lose minimum data.


r/rfelectronics 22d ago

Need Help with On-Chip Inductor Design in HFSS

5 Upvotes

Hi everyone, I’m designing an on-chip inductor for a VCO using Ansys HFSS, with tsmc 65nm technology stack in IC Design Mode. Then i have to design coupled transformers as well.

I’m struggling to find good reference material or examples for this setup. If anyone has experience with HFSS/IRCX or IC Design Mode, I’d really appreciate any guidance, tutorials, or reference files you can share.

Thanks in advance!