David, David Forbes skrev: > O Nuts of Time, > > I was recently asked to make a big PDF file of the HP AC-4 counter > modules manual that I have had on my website for a few years as a > series of jpeg files. So I did... > > http://www.nixiebunny.com/hpac4/hpac4.pdf > > These modules are used in the ancient HP 521 to 524 series of > counters. Each module handles one digit. They have four vacuum tubes > and either a nixie tube or ten neons in a thermometer arrangement. > > I have a 521C and a 522B counter on hand but they are a bit too slow > to handle the 10 MHz of modern times, having a maximum counting > frequency of 200 kilocycles per second.
A pair of phantastron setups will divide it into range. Should use up about 3 tubes. Cheers, Magnus _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
