Before working, disconnect from power and leave the instrument idle for many minutes, for the capacitors to have time to discharge.

Always be very very careful, the capacitor can stay charged at high voltage, so they can give you a dangerous shock.

The recommended procedure is that, after you disconnect the power, use an isolated wire with two contacts and touch the big capacitors to discharge them.

We have sent you a oscillator tube, the power control card and 2 capacitors, 500 pF 20KV. The red capacitors are the ones you see in the picture, one at the top and one at the bottom. They are the most probable cause of failure, start with the one at the top, it is the easiest to replace.

If it doesn't fix the problem, the oscillator tube is the second suspect, replace it.

The third suspect is the capacitor at the bottom, needs more work to replace.

Check all the capacitors and coils for conductivity, any part can make problems but the most likely to fail is 77345 (I think).

Please be careful when re-assembling it back together, don't miss any nut or bolt, there is high voltage in the chassis and vibration too.