I found an atomic clock at the world's largest vintage computer show

I thought I had the best time. Then someone brought over a cesium atomic clock, and I wasn't sure.

Segal's law: "A man with a watch knows what time it is. A man with two watches is never sure."

Some of the things I mentioned in the video:

- VCF Midwest: https://vcfmw.org
- ShadyTel: https://shady.tel
- Meinberg GPS Antenna: https://www.meinbergglobal.com/english/products/gps-antenna-converter.htm
- Pumping Station One: https://pumpingstationone.org
- Tattler Solutions WOPR rackmount display: https://tattlersolutions.com/wopr/
- Duchtronix AVR Scope Clock: http://www.dutchtronix.com/ScopeClockH3-1-Enhanced.htm
- My TrueTime Pi configuration: https://www.jeffgeerling.com/blog/2026/truetime-xl-gps-time-server-restomod/
- MacMesh: https://macmesh.xyzzy.computer
- Mr. Macintosh: https://www.youtube.com/c/MrMacintoshBlog
- L2J video on the Prototype Apple Network Server 300: https://www.youtube.com/watch?v=tupEO0mrf0c
- Quadra 800 MiSTer FPGA core: https://github.com/danifunker/MacQuadra800_MiSTer
- PicoPCMCIA: https://www.yyzkevin.com/picopcmcia/
- PC110 Motherboard Recreation: https://github.com/ahmadexp/Open-Source-PC110
- dosdude1: https://www.youtube.com/@dosdude1
- Ron's Computer Videos (helped me get some clips!): https://www.youtube.com/@RonsCompVids
- Retro Tech Foundation: https://www.retrotechfoundation.org
- TAPR TICC: https://tapr.org/product/tapr-ticc/

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2nd Channel: https://www.youtube.com/@GeerlingEngineering
3rd Channel: https://www.youtube.com/@Level2Jeff

Contents:

00:00 - Something unexpected
01:02 - NTP Demo on a bunch of old Macs
04:49 - Other YouTubers
05:24 - Hard disk clock, atomic clock, and RF station
05:59 - Oscilloscope time
06:23 - WOPRs and MacMesh
06:59 - The rack of Mac Servers
07:20 - New hardware for old systems
07:50 - dosdude1 GSM cellular demo
08:13 - This place was HUGE
08:35 - Ingenuity in time transfer
09:23 - Comparing clocks
10:05 - Sharing the best time with everyone