Not a technical question, just want to say I really appreciate your projects! I work with a group of radar engineers and they were absolutely floored by your €800 C-band polarimetric SAR drone.
Any tips for working on hobby RF/microwave projects and staying motivated while doing them? I am an EE and have a long list of projects I want to do at home, but I can never seem to find the time to do them.
I have also had issues with motivation. I had a long pause from about 2019 to 2024 where I didn't work on personal electronics projects because I didn't have enough motivation. This and last year however I have been very productive and it's hard to say what exactly changed, just felt like working on them.
I'm surprised you're not using SMA edge connectors designed for 15G. The ones you're using, with the long center pin, aren't really 50 ohm above 6G. Higher freq SMAs have really tiny center pin for SMT soldering with low capacitance.
Have you considered making something more expensive with better performance? Commercially? You mention Keysight VNA's in the $10,000+ range, but we regularly buy VNA's in the $100,000+ range. I imagine with a $1000 budget you could do quite a lot.
There's not much software. PC calculates PLL register values for correct LO and source output frequencies, and transfers them to the FPGA which writes them to the hardware. FPGA accumulates the downconverted samples from the receiver ADCs. Samples are transferred to PC which calculates ratios of the receiver outputs to get uncorrected S-parameters. scikit-rf Python library is used for calibration and plotting.
Thanks for the submission. Author here if you have any questions.
Not a technical question, just want to say I really appreciate your projects! I work with a group of radar engineers and they were absolutely floored by your €800 C-band polarimetric SAR drone.
Any tips for working on hobby RF/microwave projects and staying motivated while doing them? I am an EE and have a long list of projects I want to do at home, but I can never seem to find the time to do them.
I have also had issues with motivation. I had a long pause from about 2019 to 2024 where I didn't work on personal electronics projects because I didn't have enough motivation. This and last year however I have been very productive and it's hard to say what exactly changed, just felt like working on them.
I just want to say thank you for your work. I bought one for the lab last year and I love it. Maybe even saved my job.
I'm surprised you're not using SMA edge connectors designed for 15G. The ones you're using, with the long center pin, aren't really 50 ohm above 6G. Higher freq SMAs have really tiny center pin for SMT soldering with low capacitance.
Do you have a link to the files on github? I assume https://github.com/Ttl/vna2 is the older version?
It's not on Github, but I do have schematic at the end of the blog post. vna2 is the previous version.
Can you please create a high speed oscilloscope next? :-)
Depending on what you mean by 'high speed', this project may be of interest: https://www.eevblog.com/forum/crowd-funded-projects/haasosco...!
If you're interested in RF circuits, I highly recommend taking a look at X-MWblocks prototyping framework by https://quanticxmw.com/
It's so rare to see work at this level posted online. RF experimentation isn't as popular as it used to be. I enjoyed this article!
Have you considered making something more expensive with better performance? Commercially? You mention Keysight VNA's in the $10,000+ range, but we regularly buy VNA's in the $100,000+ range. I imagine with a $1000 budget you could do quite a lot.
Very impressive. Interesting how expensive the components get. I'm guessing it's more of a "anyone who really needs this can afford it" kind of thing.
Been following your blog for a while, such amazing depth and write ups!
TIL: Vector Network Analyzers (VNAs) tests component specifications and verify design simulations, ensuring system compatibility.
@henrikf - can you share where you got the CNC done? Thanks.
It was from JLCCNC.
Any writeup of how the software was written?
There's not much software. PC calculates PLL register values for correct LO and source output frequencies, and transfers them to the FPGA which writes them to the hardware. FPGA accumulates the downconverted samples from the receiver ADCs. Samples are transferred to PC which calculates ratios of the receiver outputs to get uncorrected S-parameters. scikit-rf Python library is used for calibration and plotting.
Any possibility of seeing the code (on github)? Seems interesting.
Really really impressive work!