Yup, but if you look closely, you'll see the little cW logo, with the W
having like wings or something. That was my clue, we've got the same
switches. CW is a huge switch manufacturer, but maybe the logo changed a
bit over the decades.
The CW part numbering system is obtuse, it
looks like a sequential bunch of numbers with no obvious way to map the
pin type to part number. You just gotta slog through one by one keeping
in mind the picture may not be correct...
Anyways. I'm pretty sure the PCB is plated through so you'll be able to suck off the solder from the solder side.
But I'm gonna ask again, what's the history of this 1A4?
I'm afraid that you can break more stuff in the process of stripping down the 1A4 to get to the switches. Just look at the fragile little common mode chokes for example, or all that mechanical cruft.
I mean there are other ways you can inject a DC offset in that signal path, like messed up position and identify pots, switches and resistors.
