Tom Verbeure
@tomverbeure.bsky.social
Plays with FPGAs. There can never be enough LEDs. Hardware engineer at Nvidia, but my views here are my own. he/him. Also @tom_verbeure at the woolly elephant and the former bird site
Pinned
Tom Verbeure
@tomverbeure.bsky.social
· Nov 22
I’m Tom. When not giving in to my test equipment addiction, I play with LEDs and PacMan.
Fixing LCD Screen Corruption of a Tektronix TDS220 Oscilloscope (and other fixes)
tomverbeure.github.io/2025/11/03/T...
tomverbeure.github.io/2025/11/03/T...
November 4, 2025 at 7:15 AM
Fixing LCD Screen Corruption of a Tektronix TDS220 Oscilloscope (and other fixes)
tomverbeure.github.io/2025/11/03/T...
tomverbeure.github.io/2025/11/03/T...
Inside an Isotemp OCXO107-10 Oven Controlled Crystal Oscillator
tomverbeure.github.io/2025/10/26/I...
tomverbeure.github.io/2025/10/26/I...
October 27, 2025 at 5:08 AM
Inside an Isotemp OCXO107-10 Oven Controlled Crystal Oscillator
tomverbeure.github.io/2025/10/26/I...
tomverbeure.github.io/2025/10/26/I...
Reposted by Tom Verbeure
My new article on Harold Black and the invention of the Negative Feedback Amplifier has just been posted. I start the story with the invention of the telephone in the 1870s, to a patent lawsuit in the 1940s.
Check it out. Let me know what you think.
emedia.digikey.com/eMagazine-Vo...
Check it out. Let me know what you think.
emedia.digikey.com/eMagazine-Vo...
October 6, 2025 at 4:10 PM
My new article on Harold Black and the invention of the Negative Feedback Amplifier has just been posted. I start the story with the invention of the telephone in the 1870s, to a patent lawsuit in the 1940s.
Check it out. Let me know what you think.
emedia.digikey.com/eMagazine-Vo...
Check it out. Let me know what you think.
emedia.digikey.com/eMagazine-Vo...
Reposted by Tom Verbeure
I'm writing about self-hosting and got wondering why ports <1024 are privileged on Linux, and require you to be root to bind to them.
Found this explanation and couldn't help but laugh. I'd always thought it was a bit of a hack.
utcc.utoronto.ca/~cks/space/b...
Found this explanation and couldn't help but laugh. I'd always thought it was a bit of a hack.
utcc.utoronto.ca/~cks/space/b...
October 1, 2025 at 9:53 AM
I'm writing about self-hosting and got wondering why ports <1024 are privileged on Linux, and require you to be root to bind to them.
Found this explanation and couldn't help but laugh. I'd always thought it was a bit of a hack.
utcc.utoronto.ca/~cks/space/b...
Found this explanation and couldn't help but laugh. I'd always thought it was a bit of a hack.
utcc.utoronto.ca/~cks/space/b...
Reposted by Tom Verbeure
Want easy capsense touchpad buttons? Just a PCB & 4 resistors. Coming soon to my Tindie store! If you want to make your own, files are here: github.com/todbot/touch...
This demo in CircuitPython but also works in Arduino w/ my TouchyTouch lib
#circuitpython #capsense #captouch #raspberrypipico
This demo in CircuitPython but also works in Arduino w/ my TouchyTouch lib
#circuitpython #capsense #captouch #raspberrypipico
September 29, 2025 at 11:10 PM
Want easy capsense touchpad buttons? Just a PCB & 4 resistors. Coming soon to my Tindie store! If you want to make your own, files are here: github.com/todbot/touch...
This demo in CircuitPython but also works in Arduino w/ my TouchyTouch lib
#circuitpython #capsense #captouch #raspberrypipico
This demo in CircuitPython but also works in Arduino w/ my TouchyTouch lib
#circuitpython #capsense #captouch #raspberrypipico
Reposted by Tom Verbeure
Cecilia Payne-Gaposchkin ✨ figured out what stars are made of ✨ when she was just 25. 🔭🧪
Her PhD thesis basically established the Harvard astro department — at a time when Harvard didn't officially allow woman students.
I wrote this little profile to mark the 100th anniversary of her thesis:
Her PhD thesis basically established the Harvard astro department — at a time when Harvard didn't officially allow woman students.
I wrote this little profile to mark the 100th anniversary of her thesis:
September 24, 2025 at 9:14 AM
Cecilia Payne-Gaposchkin ✨ figured out what stars are made of ✨ when she was just 25. 🔭🧪
Her PhD thesis basically established the Harvard astro department — at a time when Harvard didn't officially allow woman students.
I wrote this little profile to mark the 100th anniversary of her thesis:
Her PhD thesis basically established the Harvard astro department — at a time when Harvard didn't officially allow woman students.
I wrote this little profile to mark the 100th anniversary of her thesis:
Power Switch and Battery Replacement of an SR620 Universal Time Interval Counter
tomverbeure.github.io/2025/08/19/S...
tomverbeure.github.io/2025/08/19/S...
August 20, 2025 at 7:21 AM
Power Switch and Battery Replacement of an SR620 Universal Time Interval Counter
tomverbeure.github.io/2025/08/19/S...
tomverbeure.github.io/2025/08/19/S...
Reposted by Tom Verbeure
This is one of the most beautiful things I have witnessed, the craft here is impeccable.
August 13, 2025 at 6:06 AM
This is one of the most beautiful things I have witnessed, the craft here is impeccable.
I think AI hallucinated me into a paper about Modelling and Solving 2D Truss System! Something I know nothing about.
A few days ago, I submitted a blog post to Hackaday. Today I googled my name to see if it had been picked up. Instead it found this weird hit.
onlinelibrary.wiley.com/doi/10.1002/...
A few days ago, I submitted a blog post to Hackaday. Today I googled my name to see if it had been picked up. Instead it found this weird hit.
onlinelibrary.wiley.com/doi/10.1002/...
August 13, 2025 at 5:08 PM
I think AI hallucinated me into a paper about Modelling and Solving 2D Truss System! Something I know nothing about.
A few days ago, I submitted a blog post to Hackaday. Today I googled my name to see if it had been picked up. Instead it found this weird hit.
onlinelibrary.wiley.com/doi/10.1002/...
A few days ago, I submitted a blog post to Hackaday. Today I googled my name to see if it had been picked up. Instead it found this weird hit.
onlinelibrary.wiley.com/doi/10.1002/...
The Video Timings Calculator is my most popular webpage in Google Search by far, with most of clicks coming from Taiwan. Those are engineers working on monitors, TVs, laptops etc.
Traffic drops on Friday morning and ramps back up Sunday afternoon. It also drops the week of Lunar New Year.
Traffic drops on Friday morning and ramps back up Sunday afternoon. It also drops the week of Lunar New Year.
August 12, 2025 at 6:04 AM
The Video Timings Calculator is my most popular webpage in Google Search by far, with most of clicks coming from Taiwan. Those are engineers working on monitors, TVs, laptops etc.
Traffic drops on Friday morning and ramps back up Sunday afternoon. It also drops the week of Lunar New Year.
Traffic drops on Friday morning and ramps back up Sunday afternoon. It also drops the week of Lunar New Year.
3 new features for my Video Timings Calculator:
1. 10K, 12K and 16K resolutions added.
2. HDMI 2.2 96/80/64 Gbps data rates added.
3. You can share timings by copy and pasting the URL. Thanks SnowSquire@github!
Check it out here: tomverbeure.github.io/video_timing...
1. 10K, 12K and 16K resolutions added.
2. HDMI 2.2 96/80/64 Gbps data rates added.
3. You can share timings by copy and pasting the URL. Thanks SnowSquire@github!
Check it out here: tomverbeure.github.io/video_timing...
August 12, 2025 at 5:48 AM
3 new features for my Video Timings Calculator:
1. 10K, 12K and 16K resolutions added.
2. HDMI 2.2 96/80/64 Gbps data rates added.
3. You can share timings by copy and pasting the URL. Thanks SnowSquire@github!
Check it out here: tomverbeure.github.io/video_timing...
1. 10K, 12K and 16K resolutions added.
2. HDMI 2.2 96/80/64 Gbps data rates added.
3. You can share timings by copy and pasting the URL. Thanks SnowSquire@github!
Check it out here: tomverbeure.github.io/video_timing...
August 10, 2025 at 8:55 PM
The SR620 time interval counter came to market around 1986, just before VGA was a thing. But analog oscilloscopes were everywhere, so it cleverly (ab)uses the XY mode to render images.
It’s unusable on a digital scope, it’s readable on an analog one.
It’s unusable on a digital scope, it’s readable on an analog one.
August 4, 2025 at 1:07 AM
The SR620 time interval counter came to market around 1986, just before VGA was a thing. But analog oscilloscopes were everywhere, so it cleverly (ab)uses the XY mode to render images.
It’s unusable on a digital scope, it’s readable on an analog one.
It’s unusable on a digital scope, it’s readable on an analog one.
The HP 5370A time interval counter accepts an external clock of 5 MHz or 10 MHz to create a 10 MHz reference clock.
The schematic is deceptively simple, but it's really interesting and I needed a Spice simulation to understand the basics: it's a cascade of 2 injection-locked oscillators (ILO).
The schematic is deceptively simple, but it's really interesting and I needed a Spice simulation to understand the basics: it's a cascade of 2 injection-locked oscillators (ILO).
July 28, 2025 at 5:36 AM
The HP 5370A time interval counter accepts an external clock of 5 MHz or 10 MHz to create a 10 MHz reference clock.
The schematic is deceptively simple, but it's really interesting and I needed a Spice simulation to understand the basics: it's a cascade of 2 injection-locked oscillators (ILO).
The schematic is deceptively simple, but it's really interesting and I needed a Spice simulation to understand the basics: it's a cascade of 2 injection-locked oscillators (ILO).
Digikey box arrived with components for 6 different projects.
What I should have done earlier is fill in the “customer reference” field for each component with the project name. Makes it so much easier to sort through the pile.
This baggie has a 450V cap for my TDS 220 recap.
What I should have done earlier is fill in the “customer reference” field for each component with the project name. Makes it so much easier to sort through the pile.
This baggie has a 450V cap for my TDS 220 recap.
July 23, 2025 at 1:27 AM
Digikey box arrived with components for 6 different projects.
What I should have done earlier is fill in the “customer reference” field for each component with the project name. Makes it so much easier to sort through the pile.
This baggie has a 450V cap for my TDS 220 recap.
What I should have done earlier is fill in the “customer reference” field for each component with the project name. Makes it so much easier to sort through the pile.
This baggie has a 450V cap for my TDS 220 recap.
HP 5370A repair: I had the short isolated to down to the components around 2 transistors, or so I thought. Soldered power supply and input wire for easy out of chassis debug.
The thing works totally fine and creates a beautiful 10MHz ECL signal. Now what???
July 21, 2025 at 1:15 AM
HP 5370A repair: I had the short isolated to down to the components around 2 transistors, or so I thought. Soldered power supply and input wire for easy out of chassis debug.
The thing works totally fine and creates a beautiful 10MHz ECL signal. Now what???
There was (and is!) a short and a burnt capacitor on the clock reference board of my flea market HP 5370A counter.
I was able to bypass the short with a bodge.
After that, it works fine! The only thing not working yet is the circuit that was bypassed: the external reference clock input.
I was able to bypass the short with a bodge.
After that, it works fine! The only thing not working yet is the circuit that was bypassed: the external reference clock input.
July 18, 2025 at 6:06 AM
There was (and is!) a short and a burnt capacitor on the clock reference board of my flea market HP 5370A counter.
I was able to bypass the short with a bodge.
After that, it works fine! The only thing not working yet is the circuit that was bypassed: the external reference clock input.
I was able to bypass the short with a bodge.
After that, it works fine! The only thing not working yet is the circuit that was bypassed: the external reference clock input.
The HP 5370A time interval counter was one of the first to use an MC6800 CPU. To make debugging easier, it has a service board that can send the MSB and LSB of the CPU address to 2 DACs, so that programming execution can be tracked on an oscilloscope in X/Y mode.
July 14, 2025 at 6:07 AM
The HP 5370A time interval counter was one of the first to use an MC6800 CPU. To make debugging easier, it has a service board that can send the MSB and LSB of the CPU address to 2 DACs, so that programming execution can be tracked on an oscilloscope in X/Y mode.
Reposted by Tom Verbeure
One of the flea market treasures is this heavy box that’s marked “Syntheziser”. No company or model name at all, but it must be HP, based on 1820-xxxx components inside.
5MHz in, 10 and 100 MHz out.
After removing around 30 screws, you get to see this. Stunning.
5MHz in, 10 and 100 MHz out.
After removing around 30 screws, you get to see this. Stunning.
July 13, 2025 at 10:17 PM
One of the flea market treasures is this heavy box that’s marked “Syntheziser”. No company or model name at all, but it must be HP, based on 1820-xxxx components inside.
5MHz in, 10 and 100 MHz out.
After removing around 30 screws, you get to see this. Stunning.
5MHz in, 10 and 100 MHz out.
After removing around 30 screws, you get to see this. Stunning.
A shiny variac, a high precision HP 5370A time counter, a back-breaking, broken (“it worked 2 months ago!”) Fluke 6071A signal generator and a nondescript 10MHz/100MHz clock synthesizer, all for $80.
‘t Was another successful Silicon Valley electronics flea market, but being there at 6am is rough.
‘t Was another successful Silicon Valley electronics flea market, but being there at 6am is rough.
July 13, 2025 at 5:47 PM
A shiny variac, a high precision HP 5370A time counter, a back-breaking, broken (“it worked 2 months ago!”) Fluke 6071A signal generator and a nondescript 10MHz/100MHz clock synthesizer, all for $80.
‘t Was another successful Silicon Valley electronics flea market, but being there at 6am is rough.
‘t Was another successful Silicon Valley electronics flea market, but being there at 6am is rough.
This SR620 frequency counter is my best ever electronics flea market purchase. The manual has an earliest date of 1989, my unit has 1988 components in it. 37 years old. Excellent specs: SRS still sells this model, virtually unchanged!
Mine generally works fine, except when it doesn't...
Mine generally works fine, except when it doesn't...
July 5, 2025 at 6:36 AM
This SR620 frequency counter is my best ever electronics flea market purchase. The manual has an earliest date of 1989, my unit has 1988 components in it. 37 years old. Excellent specs: SRS still sells this model, virtually unchanged!
Mine generally works fine, except when it doesn't...
Mine generally works fine, except when it doesn't...
Reposted by Tom Verbeure
are you a platform/embedded developer?
do you need to interact with hardware in a semi-custom manner?
would you like to suffer a lot less doing it?
if so, #GlasgowInterfaceExplorer might be for you. the code below is all you need to build a custom testbench:
do you need to interact with hardware in a semi-custom manner?
would you like to suffer a lot less doing it?
if so, #GlasgowInterfaceExplorer might be for you. the code below is all you need to build a custom testbench:
June 28, 2025 at 3:45 PM
are you a platform/embedded developer?
do you need to interact with hardware in a semi-custom manner?
would you like to suffer a lot less doing it?
if so, #GlasgowInterfaceExplorer might be for you. the code below is all you need to build a custom testbench:
do you need to interact with hardware in a semi-custom manner?
would you like to suffer a lot less doing it?
if so, #GlasgowInterfaceExplorer might be for you. the code below is all you need to build a custom testbench:
Got myself a free wrench today!
June 27, 2025 at 4:24 AM
Got myself a free wrench today!
The view of Barcelona from Montjuic castle is nice, but the star of the show is the sea port container processing yard around the corner. I spent more than an hour looking at mesmerizing dance of straddle carriers moving containers from trucks to storage to ships. Made me want to play factorio.
June 22, 2025 at 7:29 AM
The view of Barcelona from Montjuic castle is nice, but the star of the show is the sea port container processing yard around the corner. I spent more than an hour looking at mesmerizing dance of straddle carriers moving containers from trucks to storage to ships. Made me want to play factorio.