Chemical Clocks

[Dark Sabre]

The Merriam Webster definition of sensor leaves a bit to be desired for deciding what is allowed:

a device that responds to a physical stimulus (such as heat, light, sound, pressure, magnetism, or a particular motion) and transmits a resulting impulse (as for measurement or operating a control)

But from an industry perspective I can tell you that a temperature sensor would be an RTD or an NTC thermistor.
A temperature switch would be a bimetallic thermostat.
Same things goes for pressure between a pressure transducer and a pressure switch.

The difference being that the sensors are capable of outputting a range of results, whereas the switch only works in off/on operation.

For reference see how Honeywell categorizes their products:
https://sensing.honeywell.com/sensors
https://sensing.honeywell.com/switches

TE and other companies follow the same approach:
http://www.te.com/usa-en/products/sensors.html

I definitely do not see the two clarifications as contradictory. Even without getting into the sensor/switch debate, something as simple as building up pressure could definitely press play on a tape recorder or some such device.

I look forward to seeing continued discussion on the sensors topic...

[Iwilsonp]

The Merriam Webster definition of sensor leaves a bit to be desired for deciding what is allowed:

a device that responds to a physical stimulus (such as heat, light, sound, pressure, magnetism, or a particular motion) and transmits a resulting impulse (as for measurement or operating a control)

But from an industry perspective I can tell you that a temperature sensor would be an RTD or an NTC thermistor.
A temperature switch would be a bimetallic thermostat.
Same things goes for pressure between a pressure transducer and a pressure switch.

The difference being that the sensors are capable of outputting a range of results, whereas the switch only works in off/on operation.

For reference see how Honeywell categorizes their products:
https://sensing.honeywell.com/sensors
https://sensing.honeywell.com/switches

TE and other companies follow the same approach:
http://www.te.com/usa-en/products/sensors.html

I definitely do not see the two clarifications as contradictory. Even without getting into the sensor/switch debate, something as simple as building up pressure could definitely press play on a tape recorder or some such device.

I look forward to seeing continued discussion on the sensors topic...

Ah, but the button on the recorder is no different from an electric switch (inside the recorder, that's all it is). So if switches are banned, your method also fails.

Of course, if switches are allowed (I was thinking they were also going to be forbidden), that ends the contradiction between the two FAQs. I just asked a FAQ for clarification.

[AbdullahNauman]

This is certainly contradictory and extremely vague as the response as quite literally just "No.".

However, I think that Dark Sabre does provide an interesting take on this. It possible for this to be simply referring to sensors transmitting actual data, where reaching a certain temperature threshold would have a microcontroller start the next task. On the other hand, having a simple bimetallic strip which acts as a switch in response to temperature change would be fine, no?

I don't believe gas expansion would be a very consistent or feasible for a full 120 seconds.

Chalker?

[Dark Sabre]

Ah, but the button on the recorder is no different from an electric switch (inside the recorder, that's all it is). So if switches are banned, your method also fails.

Fair enough, I didn't consider that proposal thoroughly enough.

So you could have the timer release the wound spring (uh oh, does that make it a spring timer? ) mechanism on a purely mechanical phonograph... If you can fit one in the box

I'm not going to promise you that switches are allowed, I just want to draw a distinction between sensors and switches since that was the noun in the Question. Perhaps a more verbose answer will shed some light onto the intent; till then I'm only projecting my own opinions on what qualifies as an electrically powered action.

[ScottMaurer19]

Ah, but the button on the recorder is no different from an electric switch (inside the recorder, that's all it is). So if switches are banned, your method also fails.

Fair enough, I didn't consider that proposal thoroughly enough.

So you could have the timer release the wound spring (uh oh, does that make it a spring timer? ) mechanism on a purely mechanical phonograph... If you can fit one in the box

I'm not going to promise you that switches are allowed, I just want to draw a distinction between sensors and switches since that was the noun in the Question. Perhaps a more verbose answer will shed some light onto the intent; till then I'm only projecting my own opinions on what qualifies as an electrically powered action.

If we aren't allowed to use switches then one could hit a marble which could then hit a switch. Which would kind of ruin the whole point of not allowing switches but

[davecutting]

So could we technically use the chemical reaction of a candle burning to heat a metal block of a certain length with a low-melting point solid in it that is released and begins the next action?

[ScottMaurer19]

So could we technically use the chemical reaction of a candle burning to heat a metal block of a certain length with a low-melting point solid in it that is released and begins the next action?

Yes. Biggest issue with that is the starting room temperature.

We should have a contest for the most indirect way for a timer to activate the final action.

[PM2017]

Would burning a fuse work?

[ScottMaurer19]

Would burning a fuse work?

They specifically state that fuses aren't allowed

[PM2017]

Would burning a fuse work?

They specifically state that fuses aren't allowed

Oops. Sorry.