0
votes
0answers
35 views

Measure the current on shunt basis

I am trying to measure high current 15A to 20A 1000V. There are two ways of doing it: using hall sensor, that can interface directly to micro controller using shunt resistor based. I need ...
-5
votes
2answers
73 views

2.1 speaker volume controller circuit problem [closed]

I dont know how to connect 4 wires coming out of speaker to the 3.5mm jack whick only has 3 wires in it.... I don't need volume controller. I just want to fix it so that it could work as a stereo ...
0
votes
1answer
108 views

Going from Breadboard to PERMANENT circuit but have Arduino shields attached?

I have made an Arduino project that uses a shield. I am now trying to turn it into a permanent circuit. I have flashed the microcontroller with the program, and I have all the parts I need to solder ...
-1
votes
2answers
143 views

Do any commercially available generic circuits use only discrete components? [closed]

I'm currently toying with embarking upon a totally crazy hobby project, which would prohibit the use of any component that cannot be 100% verified manually: obviously this completely rules out all ...
0
votes
1answer
64 views

How do I replace a CdS sensor in a circuit with an ALS replacement?

I am wanting to replace a resistor in a 555 circuit with a light sensor, but don't want to use the traditional CdS cell. I'd like to use an ALS such as the Everlight ALS-PDT144-6C/L451. This is the ...
1
vote
2answers
99 views

How can I maintain a fix voltage until my battery is almost dead?

I am experimenting with a simple circuit. I have an Arduino board, a proto-board and an IR sensor (that uses electricity from the Arduino board). I use a 9V battery to feed the Arduino. My problem ...
3
votes
4answers
938 views

Widely available IC for encording and Decoding DTMF data

I am planning to do some research in data transmission over the air. For this I am interested in DTMF encoding and decoding. Is there a widely available IC to achieve this? A circuit diagram using ...
0
votes
3answers
184 views

A device that wirelessly, securely posts to a server in response to door opening: off the shelf or custom-make?

I am looking for an off the shelf component for a project I am currently working on. Due to the nature of the project I cannot go into much detail about the project itself, only give a high level ...
-1
votes
2answers
187 views

Capacitors in RFID reader

I'm trying to understand a schematic of an RFID reader. Circuit: What capacitors are used - electrolytic or ceramic capacitors? I've seen schemes of RFID readers that use electrolytic capacitors, ...
0
votes
1answer
176 views

Can I change the input voltage for this temperature-controlled fan circuit:? [duplicate]

Possible Duplicate: Can this temperature-controlled fan circuit be modified for different input voltage? For the above temperature-controlled fan control circuit which is originally ...
2
votes
4answers
287 views

Why does conventional electricity flow out of + in a battery, but out of - in components?

It seems like when electricity flows out of + in a battery it should be attracted by a - end of a component, but it's not like that. Why?
3
votes
1answer
81 views

Is there a solution for keeping circuits with low frequencies small?

background I'm essentially making an mixed-signal/analog computer(to accelerate certain mathematical operations). I'm looking to create many AC filters (of different types) at low frequencies (sub ...
16
votes
3answers
1k views

What is this resistor for in this circuit?

I am studying electronics and I am currently reading/working my way through "Make: Electronics" by Charles Platt. Here is one of the circuit diagrams that he gives for making a basic burglar alarm: ...
1
vote
3answers
740 views

Where to buy an SR Latch [closed]

I am looking for a simple SR Latch. I'm new to electronics though and just doing a hobby project/teaching myself. Are SR Latches sold (I'm hoping to avoid building mine because I actually need at ...
1
vote
2answers
118 views

Looking for a USB/PCI controller that can replace a physical switch

I am looking for a component that I can drop into a circuit that will replace the functionality of a physical switch so that I can control it via computer, preferably via a standard interface (USB or ...