Is it a splitter, that may connect both outputs at the same time, or is it purely a A/B switch, so the signal never connect to both outputs at the same time?
A simple switch is easy, literally a suitable switch in a casing of some sort with connectors or flying leads.
The hard part is finding a switch with enough contacts at a reasonable price!
A splitter, that may drive two outputs at the same time, may need to be rather more complex & how it works depends on what is being passed through it:
What type of signals are they? What power source, impedance, voltage, load etc.
(Some things can be directly split and connect to two loads, others needs some form of receiver at the input and output drivers to pass on the signals).
Possible switches for the simple type - you need eight pole (or seven pole if ground/0V is unswitched, double throw - 8P2T or 7P2T, in the abbreviated naming:
See "(SWR) 1418" about a third on the way down this page - an "8P2T" configuration one, so a changeover for up to eight signals - though any ground would likely be unswitched>
Miscellaneous Rotary Switches: raise/lower lever switch, Christmas tree switch, ceramic rotary switch, rotary switch for Collins radio, Alps spline shaft rotary switch, ..
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To make one up from new parts, you would need two of these four-pole wafers:
and a mechanism to mount them on:
Or a similar switch / parts from other suppliers.
Alternatively, if the signals are all low voltage and low current, you may be able to use a cheap 9 pin RS232 selector switch and just make adapter cables to the type of connectors you need?
Suitable for 2-way computer RS232 interface switching, 2 Out. Switching : panel button switching. 2Pcs DB9 Pin Serial Manual Data Switch Box. Manual Share Switch Box: No need to unplug and plug in wires when changing from different serial devices such as printers, computers.
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