Note
Popular Electronics, Aug 1969, p. 110.
Popular Electronics, Feb 1970, p. 13. (new 4 channel models)
The first scanning type receiver? Followed in October 1969 by the Sonar FR-2514 and FR-2515.
Of the three manufactures that advertised a scanning receiver in 1970 (Regency, Sonar, and Electra), Regency has done the most advertising, and expanded it's product line far more than the others. For example, in the December 1970 issue of Popular Electronics, Regency advertised four models of its scanner.
References
Brief description. Popular Electronics, Jan 1970, p. 22.
Brief description (BCA). Popular Electronics, Jan 1971, p. 23.