RFT b/w tv with no video information

[old_tv_nut]

Originally Posted by tube tv fan

Here is B12. I was unable to measure volts pp as I am new to oscilloscopes.

Well, you definitely have a pulse at that point, so you might assume the amplitude is OK.

Here's how to know:
Look at the vertical setting of your scope. It should tell you volts per (major) division. Count the number of major divisions of your pulse height to read the peak-to-peak voltage. If you have a 10x probe (usually the case), multiply the calculated voltage by 10.

Edit: make sure your vertical switch is set to the calibrated position, and not variable gain.

If your scope is set to 10 V/Div with a 10x probe, that makes 100 v/div, so the wavefrom you posted would be about 300 v p-p, which is just fine.