Focus Coil circuits?

[mbates14]

Originally Posted by Yamamaya42

Something does not add up here...

according to frank.pocnet.net datasheets, BOTH the 17FP4 and the 17HP4 have electrostatic focus and the same bias of 12L

https://frank.pocnet.net/sheets/127/1/17HP4.pdf
https://frank.pocnet.net/sheets/127/1/17FP4.pdf
and thus are pretty much the same.
Meaning focus is p6 and magnetic focus wont work.
Is the " 17FP4" above an error? cause it does show it as ES focus.

That's what I thought it was, but it is not an electrostatic focus tube. the Tube literally has no markings though, and the box says 17FP4. See pics: