Basic specs:
Measures: Frequency, period, time interval measurement, ratio, total events
Introduced: 1953
Original price, $900 — approx. $10k in today’s dollars
Frequency measurement: 10cps to 150kcps (cycles per second, hertz has not been invented yet).
Time interval: 10uS to 27.8 hours
Includes self check
49 Vacuum tubes
Based upon AC-4A/B counter modules
Power required 260Watts
Weight 45lbs in the “portable” case
Ovenized crystal oscillator.
Stability: 10ppm per week, can be standardized to WWV (if only it still existed).
Accuracy: +/-1 count + stability
Input required +/-0.2V to 100V, positive or negative triggering.
Input: direct coupled, 1M ohm impedance shunted by 50uuF (the picofarad had not been invented).
Can provide an overflow count to allow more than 5 digits of counting
Can provide 90V to power a photo tube
With an optional circuit, can provide output for a plotter or printer
This particular unit was manufactured circa 1956 and the last cal was in 1971.
Manual:
http://ftb.ko4bb.com/manuals/24.113.155.190/HP_522B_Frequency_Counter_Service_Manual.pdfManual for AC-4A/B counter modules:
http://www.hparchive.com/Manuals/HP-AC-4A-4B-Manual.pdfHP Journal Article: Sept/Oct 1953:
http://www.hparchive.com/Manuals/HP-523B-Manual.pdf1954 catalog entry:
http://www.hparchive.com/Catalogs/HP-Catalog-1956-10-Revised.pdfRelated machine: 523B:
http://www.hparchive.com/Manuals/HP-523B-Manual.pdf Related machine, HP 524B (Circa 1952):
http://www.hparchive.com/Manuals/HP-523B-Manual.pdfHP Journal Article HP 524B, March/April 1954:
http://www.hparchive.com/Manuals/HP-523B-Manual.pdf