[AMRadio] RE: T.O. Keyer Follow-Up

Merz Donald S merz.ds at mellon.com
Thu Aug 12 14:43:47 EDT 2004

Thanks for all the many responses I received about this. Garey Barrell sent me a copy of the Madison Electronics schematic from Kees' CD and it is very close--dated 6/6/61. So I am learning  more as we go.

73, Don Merz, N3RHT

Here is a summary of the replies received so far:

The original design was by Jim Ricks, W9TO, hence the name. The Hallicrafters HA-1 "TO Keyer" came out in 1959 or 1960, and I "think" the original keyer circuit appeared around 1955, but apparently NOT in QST?  The circuit was nearly identical to the "original". I also believe this was the first keyer to use "digital" generation methods. Garey Barrell.

A detailed construction article about to build a W9TO keyer may be found in Bill Orr's "West Coast" handbook, 1962 edition, on pages 597 - 600.  The unit in the handbook seems to have a circuit that is identical to the T.O. keyers commercially manufactured by Hallicrafters. 
Alan, WA2DZL

According to an Editor's note in the article, "Transistorized Electronic Key and Monitor"  in May 1959 QST, a CK722 semi-conductor version of the 9TO keyer, the 9TO Keyer "... has not been described in any periodical, but has been furnished privately by W9TO to a number of amateurs."
Garey, K4OAH

There is a 9TO Keyer Mark II described in June 1967 QST, which adds a dot memory to the original tube design.  Grant, NQ5T

In my 1964 handbook there is a construction article on and electronic keyer on page 253.  Not being familiar with the TO circuit, I can't say for sure. Jim, W5JO
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