> > is a > "TO > > Keyer". I'd like to look this up. Does anyone happen to know the > > ballpark year when the original TO Keyer article was published?
There is a 9TO Keyer Mark II described in June 1967 QST, which adds a dot memory to the original tube design. And a transistorized version of the keyer in the May, 1959 QST. In the latter article there is a statement to the effect that the original circuit did not appear (at least to that point in time) in any periodical, but was furnished by W9TO privately to a number of amateurs. Maybe the Hallicrafter HA-1 circuit would be a close approximation, if not the original. Grant/NQ5T
