The NOTA commemoration for Apollo 11 (56 years) is always special to the public. What an inspiration to land on the moon and to have NASA ON THE AIR (NOTA) as a vehicle to use ham radio to promote these types of events.
While Chris W5HOO and Jayant KG5LJZ were able to activate W5RRR (good job guys!), of special interest was the work of Sean Cannon KK4RYN from our sister NASA station @ KSC, NN1KSC.
Quindar Tones
Sean heard MSFC’s NOTA activation on SSB and notice their use of a familiar CAPCOM beep tone, called “Quindar Tones”. Used by CAPCOM in the Apollo voice comm to the lunar vehicles, it has a distinctive signal tied to pre-PTT and post-PTT activations of the microphone.
Sean immediately wondered, “how did they do that” and “I can do that, too!”.
From Michael Seay WA5ECT’s post:
Mr. Cannon also went above and beyond after he heard the NN4SA club from MSFC on the air Saturday using the ‘Quindar’ tones (2525hz to key, and 2475hz to unkey) used in early NASA Space missions. He single handedly produced a circuit, patch cables, and keying scheme Saturday night <DIYed it in an hour> and brought it in and used it while operating on Sunday (Note: NO club equipment was harmed in the effort). Several contacts recognized the tones and effort, and one spotter who spotted N1KSC on DX-Summit called him ‘CAPCOMM 1’.
Read Sean’s excellent blog post here:
https://planetdeimos.github.io/blog/post/quindartones/
Follow-up
Sean was inspired to DIY the Quindar Tones based on hearing it from our MSFC sister station NN4SA. With a few email threads in discussion about this cool implementation, Ben AE4FQ shared that MSFC had Quindar Tones capability due to the cool work that Kevin Zari KK4YEL at NN1KSC had developed. Ben kindly offered some PCB extras that he had procured a few years back. Later, Ben also shared his PCB references here (credit Kevin Zari KK4YEL)
https://oshpark.com/shared_projects/MpvUXgKH
I’ve requested a pair of Ben’s generous offer to NOTA clubs since he had a few spare PCB blanks. We’ll see if we can integrate this into the JSC W5RRR for future NOTA events.
History and another implementation
Also embedded in Sean’s blog, but here’s this overview about Quindar Tones and the author’s own implementation. Sean followedin the legacy of updating with more modern devices (Arduino).