The Canon Canola 167 was the last of the early electronic
calculators made by Canon which used their unique side-lighted electro-optical
display elements. Canon's electronic calculators announced after
the Canola 167 abandoned the use of the electo-optical display and used
Nixie tubes for the display elements, due mainly to the tedious replacement
process required if one of the incandescent lamps in the display modules
burned out.
For examples of other early Canon electronic calculators
that use this display technology, see the Old Calculator Web Museum
exhibits on the Canon 161 and
the Canon 130S electronic
calculators.
The Canon Canola 167 offered automatic square root (not available on
previous Canon electronic calculators), seven memory registers (which
was quite a few for the time),
modes for summation of products and quotients, double-precision results
for multiplication (with results up to 30 digits in length), and many other
advanced features.
The really special thing about the Canola 167 is that it is one of only
two desktop electronic calculators ever made that utilized a small magnetic drum
as its main register storage. Most other calculators of the time used
magnetostrictive
delay lines, magnetic core memory, or electronic multi-stage shift registers
/ring-counters for storing the working registers of the calculator.
The only other
known electronic calculator to use a rotating magnetic storage system was the
Wyle Laboratories WS-01 calculator (which was quickly superseded by
the Model WS-02, which replaced
the unreliable magnetic disc with a magnetostrictive delay line).
Because of the fact that a magnetic drum relied on rotating
media (the drum, or in the case of the Wyle Labs machine, a disc), with
read/write heads positioned extremely close (typically <0.005 inch from the
media surface) to the moving media surface, calculators using rotating
magnetic memory systems were prone to damage by motion or shock. Such damage
was most likely to occur if the machine was shocked or moved abruptly
while the machine was operating, or during the "spin-up" period when the
calculator was first powered-on, and the "coast down" period after the
calculator had been powered off. Any shock or sudden motion of the machine
could cause the read/write head(s) to "crash" into the spinning media,
destroying the head(s) as well as damaging the rotating magnetic media.
Once damage occurred, it most always rendered the machine non-functional, or
caused major malfunction in the best case.
The solution was to replace the memory system, which was
expensive and somewhat time-consuming, requiring calibration once the new
storage system was installed. This led both Canon and Wyle Laboratories
to quickly abandon the use of rotating magnetic memory devices in their
electronic calculators.
If you happen
to have a surviving Canon Canola 167, working or not, The Old Calculator Museum would love to hear from you.
Please click the EMail button at the top of this page and send us a message
about your calculator.
Please note that there is a later Canon calculator with the 167 model number
called the Canon 167P.
This machine utilizes much later technology, and has no
relation technologically to the Canola 167 other than it was made by Canon.
