Query on Test Pattern Generator

[W.B.]

This has to do with a generator that provided color bars shaped as on the following YouTube clips:
- the end of this 1984 sign-off from CHCH Channel 11 in Hamilton, ON (from point 2:42 onwards)
- the end of this 1985 sign-off from KOLO Channel 8 in Reno, NV (from point 2:36 onwards) - also on this 1986 clip from point 4:33 onwards
- the end of this 1979 sign-off from TV Ontario (from point 3:57 onwards)
- this screen capture from WTVS Channel 56 in Detroit, circa 1980's
All I know is that the tones used were either 400 Hz or 440 Hz; that on the CHCH and KOLO clips, there was added a PLUGE to the EIA RS-189A bars in apparent response to the newer SMPTE ECR 1-1978 (later EG 1-1990) bars; and that it was in use on quite a few other stations in both the U.S. and Canada along the way. Would anyone who frequents this board have any specifics on the make and manufacturer of the generators that provided this kind of horizontal timing (with each bar on the top end about 98 horizontal pixels in a 13.5 MHz clock, or in microseconds, 7.26)? I know it wouldn't have been from Tektronix, whose color bar timing was quite different. Any help on this question would be appreciated.