[Cobaltblue]

Yes the actual data was just on lines at the top of the scan not normally seen altbough you could see it if you reduced the height on some sets others were still blanked by frsme flyback

They increased the number of lines the data was on to increase the speed of page selection and you could see it some of the sets we had at the top of the picture.

If I remember correctly it started with two lines I well remember the clock cracker page to help you set up the clock recovery circuit.

When the chip sets came out it reduced my 100 + bug wire wrapped monstrosity with pages selected by thumbwheel switches to a few LSI chips.

Never had much success with recovering TT from recordings myself the error rate was usually too high but it did work better toward the end of the period when I think they used more lines 8 Seems to ring a bell.

Cheers

Mike T