The HP Journal link about Sputnick mentioned today http://www.hparchive.com/Journals/HPJ-1957-09-Sputnik.pdf reminds me that the HP 523B counter used a Meacham Bridge oscillator as its reference.
I've several references - http://www.hp.com/hpinfo/abouthp/histnfacts/museum/earlyinstruments/0002 /0002history.html http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1956-07.pdf. http://www.hparchive.com/Manuals/HP-523B-Manual.pdf L.A. Meacham's patent in 1938 was also the earliest mention I know of which include a lamp as a PTC amplitude stabilizer. No doubt you've all read Rick's papers about the HP E1938A which uses a bridge oscillator. A few more bits in it than Meacham's original, or the HP 523B! 73, Murray ZL1BPU _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
