Uploaded July 2022 | Updated September 2026, 1 week ago

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We fix our Updata Link Test box by solving the mystery of the missing analog components. We X-ray mysterious Motorola modules, fight with misbehaving LC circuits, and help 1960's circuits with a dose of 1970's technology.

Ken's blog article about the X-ray reverse engineering of the Motorola modules:
righto.com/2022/06/x-ray-reverse-engineering-hybrid-module.html

Eric's new book, see first chapter:
nostarch.com/open-circuits
Order on Amazon:
amazon.com/Open-Circuits-Beauty-Electronic-Components-ebook/dp/B09WJWGB34

Apollo Comms Playlist: youtube.com/watch?v=v49ucdZcx9s&list=PL-_93BVApb58SXL-BCv4rVHL-8GuC2WGb

Links to doc:
curiousmarc.com/space/apollo-s-band-communications
virtualagc.github.io/virtualagc/QuestForInfo.html
ibiblio.org/apollo

Our sponsors
- PCBWay: fast turn PCBs, pcbway.com
- ElectroRent: electrorent.com
- Keysight: test instruments: keysight.com
- Samtec: connectors: samtec.com
- R&D Microwaves: rdmicrowaves.com

Support the team on Patreon: patreon.com/curiousmarc
Buy shirts on Teespring: teespring.com/stores/curiousmarcs-store
Learn more on the companion site: curiousmarc.com
Contact info: youtube.com/curiousmarc/about

00:00 Recap of previous work on the UDL
03:53 The PSK circuit is has some mystery modules, and missing others
07:45 X-raying the mystery modules
11:43 Figuring out the missing circuit
12:29 Experimenting with misbehaving inductors
17:58 We find the right coil to build our missing filters
19:27 Generating PSK with the new filters
20:27 Adding the missing oscillator
23:14 Final test