/r/electronic_circuits
A subreddit for all things related to component-level electronic circuits.
Component-level electronic circuits, diagrams, tutorials, design, and questions.
/r/electronic_circuits
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How would I make this? (To do list with lights)
I want to make a to do list, with toggle switches and led lights which respond to those switches - so you toggle a switch and a light bings when you complete a task.
I know / instead of working on my to do list, I'm working on building a to do list! But it looks fun and satisfying.
I know there are kids kits with just one light and corcuit in, but I'm thinking there might be a better way that just buying 10 or those.
I feel relatively confident in being able to get the woood work side of things down.
It wouldn't fixed to mains because I lack the competency to do that safely and responsibily..
Any tips very gratefully received!
22:16 UTC
How to connect control pins for these ADCs for reading from external sensors in a range of 0-5volts in parallel connection (2 ADCs) in DAISY configuration?
Original post: https://www.reddit.com/r/KiCad/s/fK6dUs8yIn
Basically I have two of these chips connected in parallel (in DAISY configuration). I want to set the reference voltage to 5 volts to make measurements between 0-5 volts.
23:08 UTC
Button matrix encoding
Im losing my mind on this.
This is an old one sided pcb for a button matrix that i need to move to an MCU.
Since its one sided they broke the matrix and ive starred myself blind on it.
How can i get this working with matrix scanning?(or another technique)
Col2 / Col3
Row1 through 4
is easy enough, so is pin 13.
its the missing col1 thats messing with me.
Its probably easy as cake, but it just wont work for me.
help?
17:02 UTC
Dual LED diode question
Have a dual led on this board that is red and blue. Red stays solid and blue flashes to make purple when in a pairing mode. In theory could I desolder the positive leg of the blue and bridge it with red to keep them both solid so it is always purple? Would there be a power issue with that?
20:17 UTC
Help with creating AM Radio?
I have tried creating several AM Radio circuits, but they have all failed to produce any noise other than a single click when being fed power. I am specifically looking for a circuit which utilizes the 2N2222 transistor or similar. If someone could comment a schematic or help lead me in the right direction, that would be great. Thanks in advance.
06:20 UTC
Can I connect a motion sensor with a doorbell?
Hi, i have the following:
Motion Sensor:
- Steren ALA-034
Wireless Doorbell Chime:
- Doorbell WL-3A-A
- Magnetic Sensor WLTX-205-A
I added some cables to the speaker connections of the motion sensor that extend for 10 meters, and I added a small extra speaker.
Now I need to add another speaker further away, so I bought a Wireless Doorbell. The problem is that plans changed, and now the door is going to stay open, so the sensor will work, but the Doorbell, being magnetic, won’t work.
The question:
I’d like to know if I can combine the sensor with the wireless magnetic "transmitter" so I can turn on and off the piece that handles the magnetic contact.
Important: I don’t know much about electronics, but I have some knowledge. It’s really hard to find this kind of accessories here, so buying one, at least for now, can’t happen; this is to avoid comments about it.
The two pins and the button that are only inside the magnetic transmitter activate the bell.
02:33 UTC
Can you help with the identification of the connection of each transistor? I know T1 and T2 make up a differential amplifier, but I don't know about the others. My take is that T3 and T4 are common emitter, but I'm not completely sure. Also, are T7 and T8 Darlington or Sziklai transistors?
17:32 UTC
This is the diagram made to represent a saw I have. Why is the "transformer" plugged "wrong"?
The grid electricity arrives, phase passes through a switch while the neuter goes directly to the "transformer".
The false transformer is built like a real one, an ironed ring with two coils. In this case of the same number of spirals. The weird thing is that the primary coil is not connected to phase and neuter but rather is in series with the condensator and the motor.
Im sure it's just another component which I just dont know of. Thanks for everything :D.
11:02 UTC
What is this Component?
Someone from the staff plugged 220V AC instead of 12V DC into our attendance machine by mistake. Repair shops in my city returned the machine saying it can not be repaired. What could be the marked component?
It was the only thing that looked burnt when I opened the machine. It was all black.
The machine has a lot of attendance data.
Suggestions on how to repair it and what other things could also be damaged.
14:52 UTC
How can I edit this frequency meter schematic to include these parts?
Hey! So I had a post a while ago that I deleted asking for some help, I'm not back with a little bit of some of my work. I have this
final schematic that our prof gave us, and we need to edit it by removing/substituting stuff in this with these:
- Control logic schematic
- Autoscaling logic schematic
- Sequencer schematic
We need to follow this hand drawn schematic he gave us. If someone is able to help let me know.
Translations are word for word:
-Baza de timp -> Time base
-TMS -> Selected measure time
-Logica de autoscalare -> Autoscaling logic
- Logica de control -> Control logic or sequencer
- Reg. de memorie -> Memory register
-Bloc afisare dinamica -> Dynamic display block
21:51 UTC
Diode orientation and function
In this Ms paint diagram, if one wants the filament on circuit B to operate on its own when circuit B switch is closed and A open but have both A and B burn when the switch in circuit A is closed and B open, is this diode spliced in able to make that happen and is the orientation of the diode correct?
14:46 UTC
Finding the usage of board
This was sent by a friend of mine, he wanted to know the details of the board and its usage. I also didn't know it can anyone help with it!?
08:35 UTC
Alguien sabe como puedo arreglarlo, no se escucha del otro lado y se safaron esos tres cablecitos);
20:50 UTC
Electronic Companat
Baby toy-Hh707k-2.4g 12v 7pin motherboard. Damage component number name
21:20 UTC
Control 7 different protoboards by 1 SPST DIP x4
The second image is how i try it but idk if it run like tinkercad in real life and i'm afraid they'll burn, please help me with any suggestion
19:13 UTC
On/off switch to one pulse
Anyone knows how to convert on/off light switch into button (one pulse signal)?
08:14 UTC
On a blank through hole board, why do people not simply run a continuous bead around the perimeter of the board as a ground rail?
Hi community.
So in my collage days I would take tons of Adderall during that time I decided to teach myself to solder etc, built valve powered guitar pedal, modified stuff.
Im 36 now, trying to get back into it and customize a cheap condenser mic and upgrade it.
https://www.instructables.com/Modify-a-cheap-LDC-Condenser-microphone/
On a blank through hole board, why do people not simply run a continuous bead around the perimeter of the board as a ground rail? Intuitively it seems like the most convenient thing to do.
What is the proper way of connecting ground to the rest of the circuit?
In schematics the rest of the process is evident as long as you know how to download data sheets, but the grounding part seems to escape me.
Thanks
14:03 UTC
multi voltage power supply
00:59 UTC
FM Radio Wiring Query - Creative Zen Z500 Docking Station
Hi, I'm looking for help on fixing a 75 ohm radio antenna that only produces static.
Background / Problem:
- I recently got a Creative Z500 (aka MF8047) docking station for a Zen Vision M music player.
- This dock has an F-type connector on the back which is connected to a telescopic aerial (see photo). This aerial is then wired internally to the Zen Vision M which can use it to play FM radio.
- The Zen Vision M detects an aerial has been attached, but I only receive static, i.e., no signal is coming through.
Wiring:
- Internally, there are 2 wires soldered as follows:
- Wire 1: It is soldered from the Zen Vision M to the back of the F-type socket that the aerial is attached to. The same wire then goes into a black device (possibly a resistor to bring it down to 75 ohms - see left of attached photo). There is another cable coming from this black device to the grounding point above the coax socket.
- Wire 2: It is soldered from the Zen Vision M directly to the grounding point above the coax socket. I understand it is the ground?
Query:
- Do you think the FM aerial has been wired correctly? I'm wondering if both wires should be connected to the grounding point given I'm only receiving static.
Note:
- I was able to test the FM radio on my Zen Vision M with a set of headphones (which is an alternative way of adding an aerial), and it worked perfectly.
22:33 UTC
Why my amplifier sound bad
Hello, recently I challenged myself to build a class A amplifier, I created a small spreadsheet to determine the values of the components I was going to use, then pass the test time I realize that there is a lot of parasitic noise and that there is no bass, I thought it came from my breadboard but even on a solder wafer the same problems occur, Will you know where my problem can come from, here is my calculation sheet, the diagram and a photo of my amplifier prototype. I use a 5V USB power supply and the signal comes from my phone.
Here are my specifications:
IC = 10mA
HFE = 100
VCC = 5V
VCE = /2 of VCC = 2,5V
VE = 20% of VCC = 1V
VB = VE + VBE = 1,7V
VBE = 0,7V
fc = 20hz
R_Headphone = 32ohm
VRE = IC x RE = 0,1mA
the formulas used:
for IC = 10mA
IB = IC / HFE
RE = VE / IC
RC = VCC - VCE / IC
C_signal = 1 / 2pi x fc x R2
C_HP = 1 / 2pi x fc x R_HP
C_RE = 1 / 2pi x fc x RE
R1 = VCC - VBE - VRE / 10xIB
R2 = VBE + VRE / 10xIB
and the result:
RC = 250
RE = 100
R1 = 5k
R2 = 2.5k
C_Signal = 3uf
C_RE = 79.6uf
C_HP = 248uf
the schematic:
and my prototype:
I didn't have any space so I wired it in mono :P
and it works but with very little bass and a lot of noise
17:13 UTC