808s are moded for streak free.
Changing cables/sources would not solved it.
The description Tully gave it is right, i do not know how to put pictures but i have some good exemple. It is not glowing, neither two direction candle light streak.l
I was able to reduce somehow the effect by hard disabling the ABL on my machine, but still there. Reducing G2 somehow lower the effect.
Based more on intuition and physics, i would say that this effect is due to a remanence of cathode emission excited at high level even after the signal is gone. As this effect is not seen on 600-700 lumens tubes (SD Sony series) i would say that it is linked with high brightness tubes like T180 on 70X series and similar on 80x series.(1100/1200 lumens)
If this it is true the only way to solve the problem is to kill the spot after the withe is gone, means working a solution to modify the G1 voltage based on the level of black inside the signal
Now, i am sure that the R762757 module is not fixed and the R762757-5 module has the fix for the 70x series.
A direct comparaison of these 2 drawings could clear the situation at least for the T180 tubes but also would gave some infos on the principle of solving the problem .
So anyone has the drawings?