Quick Start Workbooks are easy-to-follow, tutorial-style books that are designed to give you hands-on experience of using a particular software application or technology. As well as the books themselves, there is an accompanying website (www.quickstartworkbook.com).
Safety First Working with electricity brings with it two big dangers: the risk of being electrocuted and the risk of starting a fire. There is always the risk of causing a short circuit between the two poles of a battery when you are creating electric circuits, which can very quickly generate a lot of heat as the current flows uncontrollably between the two poles. If you smell burning, or if any part of the circuit feels hot, disconnect the battery immediately.
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Appreciate you sharing this video as I haven’t used this type of P.S. in nearly a year. Especially enjoyed your demonstration at end of the video. De AA4SH
I recently purchased a miscellaneous pack of components, which included a breadboard and the board shown here. There were no instructions with the pack, and this video has shown me all I needed to know.
I like what you're doing here. Please feel encouraged to add more narration on the breadboard sections, for example why you used the resistors you did and why that affects where the current goes.
This breadboard power supply can supply very less current. If we draw higher current then the SMD resistors on the module gets heated up. You can check...
Thanks, just got mine this morning. Bent pins all over the place out of the box! I think customer services need a few photos tbh! Subscribed! 😎 It's a shame you don't use your own voice. Unless you don't speak English and use Google translate for your scripts. Or maybe you have problems with your voice? (I have no legs below the knee so I know how it is!) Keep safe mate 😀
Hi Richard - the idea of the circuit is to show that if you apply a small current to the Base of the transmitter, this then turns on the transmitter to allow current to flow from the Collector to the Emmiter. I take your point though. It might have been better to say that pressing the button allows current to flow through the transistor, rather than saying it switches on the transistor.
I have used the 555 for so many projects over the years. One project was a water sensor to turn my bilge pump in my sail boat. This was in 1994 water sensing bilge pumps where not on the market at the time. Rule came out with one in 1997. I used the trigger function on the 555 to sense the salt water and this turned on a power transistor that powered the pump. Simple and reliable. 😁🛫
350 would have been absolutely fine. I just used a slightly bigger resistor just to build a bit of additional safety into the circuit so that it would be perfectly safe with any LED. Cheers, John
HI. Can this thing power a 16 channel servo driver on one side and a nano on the other? Trying to find a way to power about 3 or 4 micro servers using the pca9685 which requires its own power supply and a nano which as you know needs its own also. Trying to make a project i can put together that can just be plugged in with one cord. Thank you.
The problem with the first circuit is that the output from the pir sensor wasn't really powerful enough to properly illuminate the LED. If I remember correctly, it was only about 3mA, and you need something more in the region of 10mA at least. So what I decided to do was to use the 3mA is switch on a transistor which then allows current to flow directly to the LED without going through the sensor. Basically, the sensor isn't capable of driving a device itself, but is perfect for providing a small current to switch on a transistor.
If the LEDs are dim, try using a smaller resistor. The voltage drop across will vary for different LEDs. It will generally be between 2 and 3 volts. So for a 9 v battery, and three LEDs you might not need a resistor at all, or you might need a small one. I suggest using a 470 ohm resistor because that is plenty bi enough, but you could probably go smaller.
In the MB-102 schematics, the USB power line is connected after the 5V regulator (but before the 3.3V regulator). So when this module is powered from the USB port, all "5V" voltage pins have the actual USB voltage. In your example with a 9V battery connected to USB, the breadboard probably gets 9V.
@@quickstartworkbook1532 I did not test yet! I received 2 MB-102 last week but they are already dead. The first because I accidentally shorted the 3.3V output (bad idea) and the second started smoking after about 1 hour while doing almost nothing. That was probably a defective one (or a problem with my 12V old DC power supply?). In both cases, I measured that the 3.3V rail was getting around 10V (from 12V DC). I was quick to react and my raspberry pi pico seems fine. Anyways, I ordered a few more with a 9V DC power supply.
@@cynodont7391 I have heard of similar problems with MB-102 PSUs, whereby the voltage supplied to the rails is more than it should be. I think the quality of the product can vary quite a bit.
@@quickstartworkbook1532 Well, that was 10V after the failure. For my next batch, I will let them run a few hours with a few leds and resistors before I connect my precious RPI pico.
@@quickstartworkbook1532It's madness because a simple jig at each packing station would let them test it pdq! Akin to how they used to test incandescent bulbs. (Damn! I felt old typing that last sentence!😆)
The physical switch is just used to apply a small current to the base of the transmitter to switch it.on. if I removed the physical switch, there would always be current going to the base so the transistor would always be on. Cheers, John
Thanks. It would be very interesting a circuit about how to build a timer for this kind of sensor. Keeping the lights on for a certain amount of time like 2-5 minutes
Some motion sensors enable you to set the amount of time the signal stays high for. I've got one set up in my shed so that the LEDs stay on for about 3 minutes. I used a 12v battery with 4 LEDs and no resistor.
Hi Marie Claire. Yes it does. Each LED has a voltage drop across it of about 2v. Therefore, if you use a 6v battery, for example, and you have 3 LEDs, you won't need to use a resistor at all (3 x 2v). With 10 LEDs, you would need a 20v battery, so not really practical. I have 4 10mm white LEDs connected to a 12v battery, and that works ok. Each LED has a voltage drop of about 2.8v, so I'm not using a resistor in the circuit. Cheers, John
Change biased voltage or variable ressistor or change PNP to npn or vice versa or ultrasound reset electrical routing...that is why it cost a bank to run big business maintenance cost
I can make the circuit work with 2 LEDs, but when I try to add more none of them light up. I don't know what I'm doing wrong. I check and recheck to make sure my components are plugged into the right holes, I confirm the LEDs are working. Yet when I add more than 2 I get nothing. So frustrating.
Each LED has a voltage drop of about 2v. So, if you have 3 LEDs, powered by a 6v battery, you don't need to use a resistor. If you have 3 LEDs and a 9v battery then you would need to use a small resistor, say something around 150 ohms. Try reducing the size of the resistor you are using. Keep reducing the size until the LEDs come on. Cheers, John
R1 is there to protect the LED so needs to be in the region of 470 ohms. You could go a bit smaller, but if you go too small, you run the risk of burning out the LED. R2 is ther to reduce the current to the base of the transmitter. You could use a much bigger resistor here if you wanted too, say, 10k. If you go too big, there won't be enough current to switch on the transistor. You could go smaller as well because the base of the transmitter can cope with quite a large current range.
can you use a mix of leds? red with blues for example? if i want to have 6 leds in total 4 blue and 2 red from a 9v battery with a single resistor can i wire it like in this vid?
Hi Steveothehulk, thanks for commenting on the video. Yes you can mix LEDs. In general, coloured LEDs require about 2V; white LEDs need a bit more ... perhaps heading towards 3V. Play around with different LEDs to see what happens. Cheers, John
Hi Richard. The lower the voltage, the lower the torque and speed will be. My guess is the reduced torque would mean that you can't drive much of a load from the motor. Give it a go and see how it goes. Cheers, John
