I bought my first Closed Captioning device in 1976. PBS stations in selected cities were using NTSC Line 21/22 for all their captioning and one-way tele-texbtbo

I bought my first Closed Captioning device in 1976. PBS stations in selected cities were using NTSC Line 21/22 for all their captioning and one-way tele-texbtbox needs (CC2/TEXT). Also Sacramento NBC 3 started delivering closed-captioning in 1977. FCC didn’t standardize until 1980. I still have the decoder box.