Uploaded September 2022 | Updated September 2026, 2 weeks ago
We explain how Cathode Ray Tubes (CRTs) were invented and how they work, and hook up a few to light them up. They are as intimidating as they are awesome. But did you know that they led to the discovery of the electron, and the birth of a new field, electronics? And of course the invention of the oscilloscope and modern TV!
Link to Eric's scope clock design info:
github.com/schlae/crt-driver
Our sponsors
- PCBWay: fast turn PCBs, pcbway.com
- Electro-Rent: electrorent.com
- Keysight: test instruments: keysight.com
- Samtec: connectors: samtec.com
Support the team on Patreon: patreon.com/curiousmarc
Buy our merch on Teespring: teespring.com/stores/curiousmarcs-store
Get more info on the companion site: curiousmarc.com
Contact info: youtube.com/curiousmarc/about
00:00 Recap of previous episodes and high voltage warning
01:06 High voltage equipment and CRT basics
02:54 Geissler's discovery of the gas discharge tube
03:32 Crookes' discovery of the Cathode Ray Tube
04:41 J.J. Thomson's CRT explanation, electron discovery
06:22 Braun and Whenelt's development of a practical CRT
08:18 Main electrodes of our T527 tube
09:45 Why the cathode is at -4kV below ground
10:35 Why we need a cathode isolation transformer
11:26 First power on
12:04 Deflection plates
13:46 All the electrodes in a modern tube
15:01 How focusing works
16:30 Hooking up brightness
18:04 Displaying shapes!
19:40 Making an oscilloscope
20:57 Powering up a miniature tube
22:00 Large tube, Eric's CRT clock
We explain how Cathode Ray Tubes (CRTs) were invented and how they work, and hook up a few to light them up. They are as intimidating as they are awesome. But did you know that they led to the discovery of the electron, and the birth of a new field, electronics? And of course the invention of the oscilloscope and modern TV!
Link to Eric's scope clock design info:
github.com/schlae/crt-driver
Our sponsors
- PCBWay: fast turn PCBs, pcbway.com
- Electro-Rent: electrorent.com
- Keysight: test instruments: keysight.com
- Samtec: connectors: samtec.com
Support the team on Patreon: patreon.com/curiousmarc
Buy our merch on Teespring: teespring.com/stores/curiousmarcs-store
Get more info on the companion site: curiousmarc.com
Contact info: youtube.com/curiousmarc/about
00:00 Recap of previous episodes and high voltage warning
01:06 High voltage equipment and CRT basics
02:54 Geissler's discovery of the gas discharge tube
03:32 Crookes' discovery of the Cathode Ray Tube
04:41 J.J. Thomson's CRT explanation, electron discovery
06:22 Braun and Whenelt's development of a practical CRT
08:18 Main electrodes of our T527 tube
09:45 Why the cathode is at -4kV below ground
10:35 Why we need a cathode isolation transformer
11:26 First power on
12:04 Deflection plates
13:46 All the electrodes in a modern tube
15:01 How focusing works
16:30 Hooking up brightness
18:04 Displaying shapes!
19:40 Making an oscilloscope
20:57 Powering up a miniature tube
22:00 Large tube, Eric's CRT clock
