We back out the last remaining modification from our NASA receiver and return it to its original Apollo voice channel. If we are successful, we'll get to hear the voice from the astronauts the exact same way it was transmitted during the missions. And I hopelessly butchered the name of our hero engineer that left the helpful notes on the equipment, it's Frank Landspurg, not David Landsman! Bravo Mr. Landspurg. His obituary says that he was working for Motorola and supporting the Apollo missions, and passed away in 2014. Apollo Comms Playlist: https://www.youtube.com/watch?v=v49ucdZcx9s 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 Elevator Music Credit: Crinoline Dreams by Kevin MacLeod Our sponsors - PCBWay: fast turn PCBs, https://www.pcbway.com/ - ElectroRent: https://www.electrorent.com/ - Keysight: test instruments: https://www.keysight.com/ - Samtec: connectors: https://www.samtec.com/ - R&D Microwaves: https://www.rdmicrowaves.com/ Support the team on Patreon: https://www.patreon.com/curiousmarc Buy shirts on Teespring: https://teespring.com/stores/curiousmarcs-store Learn more on the companion site: https://www.curiousmarc.com/ Contact info: null 00:00 Our Apollo receiver has been modified 05:20 Reverting the modification 07:41 Retuning the filter assembly 11:40 First receiver tests 13:38 How to extract downvoice with a ham radio 15:45 First voice trials, not working! 16:49 Tracking the fault in the spacecraft transmitter 20:35 Receiving downvoice! Correction: 03:26 Frank Landspurg (not Landsman) Correction: 05:09 Frank Landspurg (not Dave Landsman)