I decided to remove the color hack to my SPRINT ONE cab. In my spare parts I had a SELTI B/W monitor. I recapped it and powered on it I could see a very strange image shape (attached). I used as signal test my ASTRO WARS cabinet that was close to my desk...
Once I replaced the YOKE I had a good result (second picture)
My question is: what can cause that kind of distortion? It seems to involve both H and V coils but actually I dunno.
I'm asking that because I want to be sure the yoke is definitely damaged before to consider it rubbish