BK 2120B Fuzzy Screen

[mark_brook]

Hi guys I got an used Bk Presicion 2120B which seems not to adjust the focus and when i try to calibrate don't show me the usual trace,I added some pictures of the screen maybe someone can give me a hand to fix it,I got the  schematics from the web  but seems to be incomplete  specially on adjustments procedure.

I got  skill on electronics but never work before with an oscilloscope and i don't wanna mess with the adjustments without knowing what to do or how to do it,

Pic 1 shows a dot pushing the trigger XY push button but see the dot is not rounded its looks square,pic number 2 show not the line as usual when you set it up and pic 3  shows the way it show when I try to calibrate CH1 with 2 V p-p calibration port.

I will appreciate your help by the way i got the 144 volts on P801 pin 7 and the 5 ans the 12 volts on that connector.

[med6753]

Check the resistors in the focus divider circuit. They are prone to going open.

I have an older 2120 and have had it happen twice.

[mark_brook]

Ok but I'm asking for the service manual for that model to verify the circuit of the focus i got one from the web for the 2120  but its an older version its more alike but seem to works ok  according to that schematic