28 Feb
2012
28 Feb
'12
11:17 a.m.
[TV getting vertial sync from tha mains]
I think it goes back more to the spinning disk TV
format from the late 30's.
http://www.tvhistory.tv/index.html Dig here for more history on TV
According to all the published information I have 9including
instructions for buildign such a receiver and scheamtics published at the
time, there was no vertical synchronisation in this system.
The drive motor for the disk had a synchronistation device conisiting of
a toothed wheel between the poles of an electromagnet. This provided a
line synchronaistion, ensurign the picture lines started in the right
place but which line started the frame wasn't specified. Rather the
viewer had to mnually retard the disk (press a thumb on it) until the
picture didn't ahve a bar across it.
-tony