A signal-carrying circuit that can send output signals to
two or more different locations, depending on the state of the
mechanism. These may be toggle circuits, where the state of the
switch changes after each use, or permanent switches that retain
the same state through many uses until a change is made with a
separate signal.
More generally, any circuit may be referred to as a switch, if it
can alter its output based on stored information. For example, the
following simple mechanism based on an eater2 was discovered by
Emerson J. Perkins in 2007. It either reflects or absorbs an
incoming signal, depending on the presence or absence of a nearby
block. The block is removed if a reflection occurs.
The switching signal here is a glider produced by a high-clearance
syringe variant found by Matthias Merzenich. The syringe is not
technically part of the switch mechanism; any standard Herschel
source can deliver the signal to the block factory (the two
eater1s on the right side of the pattern). Alternate converter
mechanisms could also be used to place the block.
An earlier example of the same type of one-time switch mechanism,
also mediated by a block, can be found in the NW34T204 H-to-G. See
also bistable switch for a very robust and versatile toggle switch
with two input lanes and four possible outputs.