The flyback (retrace) lines are visible because the brightness and contrast are too high. As you pointed out, the internal video signal is 2.1v p-p and you are supplying 1v p-p. If you use a video amplifier to boost the signal you will be able to turn the brightness and contrast down.
i still think youre seeing the lines coz the intensity of the beam is wayyy to bright..you should be able to bring it down so you dont see the lines but still able to see the text.. ..saying that.. failing adjustment..the tube may be toast... ive got an old b&w screen in an old door intercom system (camera too).. i need to pull apart and use in a project.. you should be able to use a simple arduino TV out (composite) to generate a picture you can use to test and adjust...
Some comments in the Part 1 video suggest disconnecting the VIF input (pins 1 & 28) ... I did this, pretty simple ... break one track and disconnect one link ... but made no difference in my case. Adjusting contrast/brightness makes no difference. Only thing I have tried yet is impedance match the 75Ω input ... but I don't think this would affect the retrace lines ... so yeah, I think this Xmas present from 1986 might finally need retiring!
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The flyback (retrace) lines are visible because the brightness and contrast are too high. As you pointed out, the internal video signal is 2.1v p-p and you are supplying 1v p-p. If you use a video amplifier to boost the signal you will be able to turn the brightness and contrast down.
I would tidy up those four pads that no longer have their parts. @19:43 it looks like you have a bit of a blob between pins 4 & 5 on the AN5151N.
i still think youre seeing the lines coz the intensity of the beam is wayyy to bright..you should be able to bring it down so you dont see the lines but still able to see the text..
..saying that.. failing adjustment..the tube may be toast...
ive got an old b&w screen in an old door intercom system (camera too).. i need to pull apart and use in a project..
you should be able to use a simple arduino TV out (composite) to generate a picture you can use to test and adjust...
Some comments in the Part 1 video suggest disconnecting the VIF input (pins 1 & 28) ... I did this, pretty simple ... break one track and disconnect one link ... but made no difference in my case. Adjusting contrast/brightness makes no difference. Only thing I have tried yet is impedance match the 75Ω input ... but I don't think this would affect the retrace lines ... so yeah, I think this Xmas present from 1986 might finally need retiring!
@Brfff Just tried, I'm having these retrace lines as well. Too clueless to actually try something, though.