A rectifier issue would affect most coils. The spoon switch is the first thing to check. Make sure it's properly gapped and manipulate the platter to make sure the finger can't get stuck anywhere. It is worthwhile to test the transistors on the driver board as well and see if the transistor driving this pop is in spec. Last but not least, floating grounds can cause coils to lock on so the board set should have ground mods done and the interconnect cable should be checked and recrimped if necessary.

Some people convert their System 1 pops to use system 80 pop boards. This makes lock ons less likely and gives a stronger more consistent pop but it doesn't not remove the need to do the above things.

Zacaj is correct. I read the Schematic wrong.

the rectifier is easy to test. Pinwiki has instructions on how to test it using a dmm in diode mode. Or you can measure the inputs to it in VAC ~27 and the outputs in VDC ~24.

If it fails any of these then certainly replace it

You want the pop spoon switch as close as possible without accidentally triggering. System 1 pops are directly driven from the spoon switch