Heat detectors are very useful where there's a risk of deliberate smoke or haze on a regular basis that would cause false triggering of a traditional smoke detector. The complicated units can sense a sudden increase in temperature associated with a fire, while simpler units just have a set temperature threshold.
This one has a very weird bit of circuitry that had me double checking the schematic. If you've got any ideas about it then leave a comment down below.
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This one has a very weird bit of circuitry that had me double checking the schematic. If you've got any ideas about it then leave a comment down below.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
http://www.bigclive.com/coffee.htm
This also keeps the channel independent of YouTube's advertising algorithms allowing it to be a bit more dangerous and naughty.
Perhaps they use this board in a mains powered unit as well ? So could be a variation in supply which would affect the thresholds?. As you say a battery version won't be affected by this 🤔
Can you recommend any uses, for an expired Carbon Monoxide alarm?
Clive, It's call a "rate of rise of heat detector", I used to install them back on the 80's, very effective
For some reason, I find the photo of the white circuit board especially gorgeous. Kudos to your photography, Clive, and to your printer. The zoomed, high-quality photos really help to see what's going on.
BTW, I only discovered your channel relatively recently, but I think I've watched at least 50 videos. Very addicting. Besides the electronics, as an American, it's nice to learn about the Isle of Man, the UK, Scotland, and even your quirky friends.
Keep up the good work, sir.
–pred
i thought all diodes that are orange with that black stripe were zener diodes. is that not true?
Why is the GP Supercell marked as containing lead?
Could you use the sensor as a ion scanner sort there have at airports to detect drugs. Sort you see at airports on the documentarys
We have inspection microscope in my laboratory
I have thermistors. I can get lots off them from amazon
What do you think about Stefan Molyneux's videos?
Zener might be in the circuit as an error and only useful when the board is totally populated and linked to other devices, if they are battery powered I ver several devices the excess could build up
Pin 2 is the TX/RX pin for communications between devices.
Does anyone watch mymatevince along with big clive?
It seems that the 2N7000 transistor is susceptible to static electricity; just soldering the transistor with an ungrounded soldering iron might blow it out. Once the transistor is mounted in the circuit board it is usually not a problem. However, with the thermal-resister sticking out like that, where someone could touch it; the "mystery" zener diode provides some protection by limiting any external static charge that might accidentally be induced directly into the transistor and causing it to blow out.
I think this is some kinda of bias for gate of the fet. though the leakage current is very low Fets are voltage controlled so need very little current to affect them. Thats the only reason I could see how desoldering the diode would change sensitivity it must have changed the leakage of the diode they are very sensitive to heat.