[GreenKeys] Stevens-Arnold Polar Relay

[Jim Haynes]

I remember the name "Millisec" associated with Sigma relays at one time.

Those winding resistances are awfully high for use in ordinary TTY
circuits.

At one time - mid 1960s - Stevens-Arnold was making packaged tuning fork
oscillators.  I was working for Teletype, where we were using unijunction
transistors as bit-rate timers.  They had to be adjusted.  It seemed to
me that a tuning fork oscillator might be a lot nicer - just plug in one
with the frequency needed.  That's fine for transmitting, where the bit
timer just runs all the time; but for receiving we need one that stops
between characters and produces the first pulse a half period after being
told to start.  I asked Stevens-Arnold if it would be possible to make
a tuning fork oscillator with a hold-off of some sort so the oscillator
could start and stop.  Next thing I knew was that Mr. Stevens or maybe
it was Mr. Arnold told us he was coming to visit with a sample.  Must
have thought we were thinking of something that every Teletype machine
would use, not just the small quantity we would use for the high-speed
tape product line.

So we put it on the bench and he showed us that it could indeed be
started and stopped and give us the first output pulse about half a
period after being started.  And the asking price seemed quite
reasonable.  But there just wasn't any enthusiasm in the company
for changing the design to make use of it.  Perhaps because the cost
of adjusting the existing bit timers fell mainly on the telephone
companies that used the product, rather than on the factory.  Or maybe
they were so stable that they almost never needed adjustment.