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Contact Kees Talen, K5BCQ (Auston, TX) .. with your specific questions.
Michael F. Elliott, W8KRR (SK; April 20, 2006) was the designer for the development of the Heathkit SB-104.
Released in 1974, it was the FIRST transceiver to incorporate solid-state design, come with a digital frequency readout and be priced for the mass market.
The Japanese were still using earlier tube designs (for example, Yaesu FT-101)
The SB-104 was a mainstay for Heath until 1982, when radios that covered the new WARC bands superseded it.
It was one of the last Amateur Radio kits that Heathkit developed.
Later, Michael was influential in the design of the Drake TR-7. This transceiver was the standard for competition-grade transceivers in the late 1970s and early 1980s.
In his 1979 QST Product Review, David Sumner, K1ZZ, called the TR-7, "...the most convenient this reviewer has ever used. The styling is functional, and is similar to that used in modern, high-fidelity audio equipment." Even today, he calls it "the breakthrough radio of its time."
These two transceivers represented state-of-the-art technology from two American manufacturers.
Michael Elliott received his BS in Electrical Engineering from Northwestern University (Chicago) in 1963.