VaKraVaK wrote:

Jeff Wisnia wrote:

counterclockwise. The only left handed opening threaded cap I've
encountered is the one on the storage can for my Curta Calculator, and


So you have a Curta Calculator? :-O


Yeah, I still have my Type 1, but I sold the (larger) Type 2 when we
sort of got tired of sports car rallying some years ago.

I may well have built the world's first motor driven Curta. And if
memory serves me I built a copy of it for some fat cat in Connecticut
who just HAD to have one too. Those days were prior to the ubiquitous
solid state portable calcuator takeover.

Circa 1961 I built a DC motor driven worm gear reduced "cranking box"
for the Curta which coupled to its operating shaft through a hole bored
in the Curta's bottom plate. A one direction roller clutch in the drive
allowed also using the Curta's crank in it's usual fashion without
having to take it off the cranker box. I still have that rig kicking
around somewhere in my basement.

We used it for rallying. I coupled a geared down microswitch to the
car's odometer cable so it closed once every hundredth of a mile of
travel and triggered the motor drive into cranking one turn of the
Curta's shaft. A little relay, microswitch and transistor in the drive
unit insured it would only make one turn each time the odometer switch
closed. It had to wait for the odometer switch to open and close again
to trigger another turn.

Setting a "minutes per mile" factor for the average speed of the rally
leg we were on into the Curta made the Curta's "product" output number
tell me how much time it "should" have taken to get to that point on the
road. Comparing that number with a stopwatch let me know whether to tell
SWMBO (Who was the quite aggresive driver of our team.) whether to speed
up or slow down.

I've often thought that if some folks put as much time and energy into
their "real" jobs as they do for thier "hobby" ones, they'd be captains
of industry before they were 30. G

I kept some photos of those halcion days. Forgive me if I've posted this
link here before, but the years are taking their toll on my short term
memory...

http://home.comcast.net/~jwisnia18/temp/rallying.html

Thanks for the mammaries...

Jeff

--
Jeffry Wisnia

(W1BSV + Brass Rat '57 EE)

"Truth exists; only falsehood has to be invented."