New p5 Herschel technology
The circuit's p5 limitation is somewhat mitigated by its reversibility -- there are two mirror-image ways to receive the two gliders, whereas most tandem gliders need either a left- or right-handed receiver. (Some pairs of gliders with two-cell separation, usually produced with the assistance of a boojum reflector, can be received ambidextrously by standard receivers -- but this significantly alters the timing of the circuit.)
Depending on the position of the block, either of the two gliders can be chosen to trigger the Herschel output, while the other one resets the circuit. The circuit can also be hooked up to any glider output of a Herschel track for use as a period doubling fanout device, or a two-state track switch (two circuits on two glider outputs with alternating block positions).
Original p5 pulse divider by Dietrich Leithner.
p7 and p46 versions: Stephen Silver, 31 May 2001.
p22 version: David Eppstein, 1 June 2001.
p104 version: Scot Ellison, 24 March 2003.
p36 version: Jason Summers, 26 March 2003.
It would be nice to have p6, p8, or p9 versions, but unfortunately no pipsquirter or other sparker below p10 seems to work with the current mechanism -- p7 is a special case.
Pulse dividers can be used as period doublers, but the "reset" glider is actually period-independent. The p104 case shows how the necessary one-bit spark can come from any periodic glider source.