Nuclear Weapons Material

I get the impression that PAL is a little more complex than that, one of the reputed goals is to prevent a weapon from being easily modified to go around safeguards. Playing with just delays can be overcome by characterizing delays in a dismantled weapon.

What I had heard was the the delays were implemented by varying the chemical composition of the explosive lenses around the plutonium core to modify their detonation rate. This prevents replacing the electronics to circumvent the security.