Vertical interval signals on 405

[Terry]

It never occurred to me that 405 had VITS. I had thought of VITS as being more modern than that.

I can't put a precise date on it but the BBC started using it not long after I started work in 1960, so 61 - 62 at the latest.

I remember that the first time I saw them in all their glory was on a Bush TV53 where they appeared very prominently about half an inch from the top of the screen.

Replacing the field output valve restored things to normal.

I can't remember any precise details but there were a few sets around where the designers had continued to take full advantage of the entire blanking period a long time after everybody else was using much faster designs and these sets needed to be modified. I have a feeling that one was a particular PYE model.