Zener diode substitutions

[strat68]

I'm building a Crowther Hot Cake that calls for a 10v zener.  Will a 9.1 volt work OK?
Thanks

[mauman]

I'm looking at the Aion tracing log schematic, for reference, and at Z1 which is the 10V zener in the power section.  If that's the one we're talking about, it protects the circuit in two ways.  If you connect 18V power instead of 9V, this zener limits the voltage to 10V and shunts the excess to ground.  Or if you put in 9V backwards, it shorts your power supply to ground. If you're careful about power supplies, you can omit it completely.  Or you can substitute a 1N4001 (4002, 4003, etc) in the same orientation, it will protect from reversed power but not over-voltage.  I wouldn't recommend a 9.1 V zener, since many power supplies operate right at that 9.1 to 9.3v range, and you might have a continuous current leak to ground, stressing your power supply and the zener. A 12V zener would be fine.