As many have observed, there are only three names in oscilloscopes: Tektronix, Tektronix, Tektronix. The Tek T922R (shown above) is the classic logging truck scope; it is actually a repackaged version of the plastic case T922 (shown below).

Tektronix was founded in 1946 by Howard Vollum and Jack Murdock.  Vollum, recipient of the Legion of Merit medal for his wartime work on radar, set out to improve the awful oscilloscopes of the day. Vollum went to work in his parent's basement and created the 501, a machine weighing almost as much as its inventor.  The commercial successor to the 501 was the 511, the world's first triggered and calibrated oscilloscope.  Tektronix is based in Beaverton, Oregon, and maintains operations in 25 countries.  Test and measurement related sales topped one billion dollars in 2000.  Visit the Tektronix website to see the latest and greatest incredibly expensive test equipment.

The T900 Series was introduced in 1975, first appearing in the 1976 Tektronix catalog.  The line included the 10 MHz single channel storage T912, the 15 MHz single channel T921, the 15 MHz dual channel T922, the 35 MHz T932, and the 35 MHz delayed sweep T935 models (the T932A and T935A were 1978 updates).  The T922R was the only rack mount oscilloscope in the T900 Series (the R suffix indicates rack mount).  The T922R was also designated as the OS-287/F by the military, and an official looking military name plate is sometimes seen on the front or back of scopes acquired as military surplus.  The T922R was introductory priced at about $1,220.00 in 1976, and was priced at $2,095.00 in the last catalog in which it appeared in 1984.  The rarely seen Option 1 added a fourth vertical mode pushbutton (labeled DIFF) which, when pressed in alone, inverts the Channel 2 signal and displays the sum of both channels (it has other functions when used in concert with other mode buttons).  Earlier production T922Rs have a neon power indicator pilot lamp, while later production models have an LED indicator.  The T922R was last produced in 1984 (but may have been sold as late as 1988 or 1989), and long term support from Tektronix was ended in 1995.  Tektronix no longer stocks parts unique to the T900 Series, and has farmed out "best effort" support to Verizon (GTE).

Tektronix actively sought comments from the well logging industry while the T922R was being developed.  Prototypes were actually left with selected logging companies for evaluation.  Our good friend Paul Knight, then with The Western Company, was among those who made suggestions that helped shape the design.  The T922R has a very rugged face to support the heavy 70 mm cameras used for cement bond logging in those days.  It has rear switch selectable inputs not usually found on even rack mount oscilloscopes.  It has a bright display (useful in sunlit logging trucks), using a nominal accelerating potential of 12.4 kV.  It has scale illumination (useful for night time logging). It has user selectable chop or alternate mode for dual trace display, and a single sweep feature.  And it has internally selectable Z-axis polarity.  Except for the bright display, all of the foregoing features are present only on the T922R version, and not present on the plastic case T922.  The T922R occupies just 5-1/4 inches of vertical standard 19 inch rack space, and is 17 inches deep (requiring an 18 inch deep rack cabinet).

AnaLog Services, Inc. usually has reconditioned Tek T922R scopes in stock.  We also repair and recondition customer's oscilloscopes.  Many parts are no longer readily available; we actively acquire scopes for parts, including the plastic cased T921 and T922.  See T922R Service Notes if you work on these beasts.  As a courtesy we offer the T921/T922/T922R Manual, for download (14.3 megabyte pdf file).

Much of the historical information presented above came from Stan Griffiths; visit Stan's Scope Site, and the Tektronix Resource Site which he co-created.