We build a Phase Locked Loop (PLL) FM demodulator for extracting the Apollo downvoice from its subcarrier, using the classic 7046B IC. But in the meantime, as luck would have it, NASA's own S-band receiver's PLL seems to have gone bonkers, and we can't lock to the spacecraft microwave downlink anymore! So we'll get very hands on with PLLs in this episode. Expect a healthy dose of PLL elevator music.
Apollo Comms Playlist: https://www.youtube.com/watch?v=v49ucdZcx9s&list=PL-_93BVApb58SXL-BCv4rVHL-8GuC2WGb
Older video on Fractional-N PLLs, used for frequency synthesis: https://www.youtube.com/watch?v=z-50pSc_wg8
Links to doc:
https://www.curiousmarc.com/space/apollo-s-band-communications
https://virtualagc.github.io/virtualagc/QuestForInfo.html
https://www.ibiblio.org/apollo/
https://www.ibiblio.org/apollo/Documents/HSI-481260.pdf
Stuff that supports the channel:
- Support us on Patreon: https://www.patreon.com/curiousmarc
- Amazon links for the tools I use in the lab: https://www.curiousmarc.com/amazon-links
- Channel merch on Fourthwall: https://curiousmarc-shop.fourthwall.com
- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): https://teespring.com/stores/curiousmarcs-store
- Contact info: https://www.youtube.com/curiousmarc/about
Elevator Music Credit: Crinoline Dreams by Kevin MacLeod
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