Electronic component assembly
- Thread starter A[L]C
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The pot does not control the discharge of the timing capacitor. It is simply being used as a potential divider to provide an input signal to pin 9. Some calculations, based on the pair of 10K resistors in series with the pot, show the signal can go between 1.1V and 11V. (Here I am assuming the two 10K resistors either side of the pot in the images are R10 and R16 in the datasheet).
Adding a larger pot will not help as the higher resistance decreases the lowest possible voltage on pin 9. You won't get much lower than 1.1V!
You can, however, keep the pot and simply change the resistor value of R11 to a higher value. This will not affect the charge time of the cap C4, as the resistor is in parallel when the cap charges, but in series when the output of the third opamp disappears. (There is a diode, D2, that prevents the cap from discharging to ground via LED1)
Doubling the size of R11 will give you double the amount of time (give or take). I don't know the resistor value in that kit so you will need to figure out what you need!
Adding a larger pot will not help as the higher resistance decreases the lowest possible voltage on pin 9. You won't get much lower than 1.1V!
You can, however, keep the pot and simply change the resistor value of R11 to a higher value. This will not affect the charge time of the cap C4, as the resistor is in parallel when the cap charges, but in series when the output of the third opamp disappears. (There is a diode, D2, that prevents the cap from discharging to ground via LED1)
Doubling the size of R11 will give you double the amount of time (give or take). I don't know the resistor value in that kit so you will need to figure out what you need!
Wow you are one smart cookie!!
Once I've made the box i'll be looking in to adding an external enclosure with a PIR sensor which I would want to wirelessly trigger the led strip. Think I've found the best brains to pick!
Regarding the main box construction, what's the best way to join multiple cables together?
Once I've made the box i'll be looking in to adding an external enclosure with a PIR sensor which I would want to wirelessly trigger the led strip. Think I've found the best brains to pick!
Regarding the main box construction, what's the best way to join multiple cables together?
Pick away!
As for joining cables, it depends. I would normally say solder + heatshrink. another option is to use terminal blocks. This would make it easier to fiddle.
For your enclosure, I would make sure it is somewhat water resistant if you will be using it around water! A 12V battery can do some damage if it is shorted!
As for joining cables, it depends. I would normally say solder + heatshrink. another option is to use terminal blocks. This would make it easier to fiddle.
For your enclosure, I would make sure it is somewhat water resistant if you will be using it around water! A 12V battery can do some damage if it is shorted!
A crimped splice for sure. I build looms for F1 cars and we find crimps to be more reliable than solder provided you correctly fill the crimp. Otherwise best solder splice would be to strip all you wires to at least 6mm and tie them level with some cord. Then get some very fine gauge bare single core wire (maybe 30awg depending on how big your splice wires are) then wrap that around the bare wire tight from top to bottom like a solenoid then solder and cover with heatshrink.
Overkill maybe?
Overkill maybe?
What about one of the wago spring fit connectors?
For those of you who are interested, this is an example of one of the commercially available units..
Rather than use sound, this guy has managed to intercept the signal sent from the alarm to the receiver to trigger his light. I think this will cause problems though as you could potentially pick up someone else's alarms!
Regarding the PIR component I mentioned, this is a much more advanced unit which hooks in to the alarm receiver, but mine will hok back to the bivvy box and trigger the light and a buzzer.
For those of you who are interested, this is an example of one of the commercially available units..
Rather than use sound, this guy has managed to intercept the signal sent from the alarm to the receiver to trigger his light. I think this will cause problems though as you could potentially pick up someone else's alarms!
Regarding the PIR component I mentioned, this is a much more advanced unit which hooks in to the alarm receiver, but mine will hok back to the bivvy box and trigger the light and a buzzer.
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Overkill? Perhaps.
Fiddly? Yes!
It'd drive me mad doing that more than a couple of times!
