Tai-Hao switches

Brief notes on Tai-Hao’s APC series of keyboard switches.

Reversible switch bases

Some APC switches have an interesting characteristic: the base is reversible. There are at least two possible reasons: double-pole operation (DPST) and ease of assembly. DPST seemed unlikely, and these extra holes were not present in the older APC-branded switches with wide click leaves, and they are often not present now.

Tai-Hao explained that the reversible base was introduced when increasing demands led to the introduction of mechanised switch assembly. It wasn’t the humans who had been manually assembling the switches who needed assistance, but rather the machinery that was introduced to fill this role. In fact, at this point, both the switches and the keyboards were being hand-assembled.

Improved machinery later removed this requirement, so the second pair of holes was removed.

See also

These Tai-Hao pages date back to 2016 and subsequent work was added to the Deskthority wiki. See the Tai-Hao switches wiki category for more up-to-date information.