We read the following from an installation guide:
http://www.academypendulums.com/pdf/Mark2FoucaultInstallation.pdf
“ Pay close attention to the photo beams alignment. This adjustment can effect the Ball’s precession around the pit. It may require a couple of days to determine if precession is operating properly. Precession is a function of the Earths rotation. ”
We are instructed to spend several days adjusting the alignment of the photo beams, which affects the pendulum's precession, an element which is supposedly a function of the earth's rotation, until we have determined that the "precession is operating properly"
You left out the preceding two sentences from the above quote:
"It is important for the photo beam adjustments to be made accurately for power to be applied equally in all directions to the armature. Two pairs of photo beams trigger the magnet’s power as the cable swings through the center."
This is the exact opposite of what you are alleging. It is crucial to calibrate the photo beams that trigger the swings "for power to be applied equally in all directions." If the power isn't applied equally then you don't have an unbiased swing.
Modifying the alignment until you achieve your desired result and then passing it off as a demonstration of the earth's rotation is called fraud, QED.
Since when are you against calibrating an observational instrument? You seemed to be calibration crazy when it came to talking about water level tubes just a few threads ago.
And as mentioned above the alignment calibration is to make sure the power is applied equally in all directions so it doesn't influence the swing direction.
The word "calibrate" doesn't even appear in that section. You are just making things up.
The sections say that we need to spend several days aligning something that affects the precession but makes no reference to "calibration" or how we are to calibrate it .
I’m not making anything up. I used the word calibrate as in adjusting the photo beams to make sure power is applied equally in all directions to the armature.
Much like you did in reference to water level tubes:
What accuracy? The device needs to be able to be calibrated before one can say how accurate or close the method is.
Much like all water tubes to be at equal height the calibration here is similar: Making sure the power is supplied equally so as not to interfere in the instruments measurement of the precession predicted for its latitude.
The same company that manufactures these types of pendulums, Academy Pendulum, and from whose manual you quote-mined, misinterpreted and put in the wiki, states that when trouble shooting:
5. No progress or progression stops at one point
A. Check for armature to magnet interference. Adjust cable as needed
B. Check for leveling on the magnet
C. On old units check for O-ring damage on the armature or safety hub
D. Check for cable damage at the pivot
All of which is in reference to making sure the pendulum moves freely. Not an adjustment to force a specific progression.
The point is these pendulums progress according to their latitude in a predictable manner. American Pendulum has over 100 installations since the 50’s in universities, schools, & museums around the world, at varying latitudes, meaning, as the manual states: "At the North pole it will make one revolution every 24HRS, while at Florida’s latitude it may take up to 48HRS.”
Do you have any evidence that these devices are somehow manipulated to exhibit the progression around the pit that is in lockstep with what is expected for a given latitude?