how can I measure AC voltage of bridge diode on PCB of CRT TV?

[bshi02]

I read below article and I want to measure AC voltage of bridge diode on PCB of CRT TV with switching on.
https://www.electronicsrepairmadeasy.com/2016/06/lg-21-crt-television-intermittent-dead.html
But as far as I know,When I measure any voltage in HOT area of CRT TV's PCB,I should place black probe to negative pin of The biggest capacitor(main filter capacitor) in Hot area.
Then If I measure AC voltage of bridge diode(TS4B05G) which is located in Hot area of CRT TV,After setting analouge meter to AC voltage mode,Should I place black probe to negative pin of The biggest capacitor(main filter capacitor) in Hot area and place red probe to #pin2(AC) or #pin3(AC) of soldering point of bridge diode(TS4B05G)?

or Is it not necessary to place black probe to negative pin of The biggest capacitor(main filter capacitor) in Hot area when I measure AC voltage of bridge diode(TS4B05G) but I only need to place black probe to#pin2(AC) and red probe to #pin3(AC) of soldering point of bridge diode(TS4B05G)??

[wasedadoc]

Your final paragraph is correct.

[MathWizard]

I don't like probing by hand much of anything AC powered, especially if I don't know the circuits. Do you have alligator clips, or a soldering iron ? With the power off I'd find solid places to attach clips, or solder on wires, and clip onto them.

If you're not sure about using a DMM, I'd say read up on some safety stuff too. Modern TV's can still have some pretty high voltages in them, even after turned off for a while.

[CaptDon]

If you want to measure the A.C. input voltage to a bridge rectifier wouldn't simple logic tell you to place your meter across the two A.C. input terminals of the rectifier?? And likewise to measure the D.C. output of the bridge you would measure across the + and - output terminals. You better be using a battery operated meter if you are probing around in the hot side of the SMPS. And be aware that on the output side of the SMPS the switching frequency could be 20KHz to 50KHz and switching waveforms in that area require an oscilloscope. Be careful and don't take any measurements in the hot side of the supply with equipment that is grounded (like a scope) unless you are using an isolation transformer to feed the device under test.