A variable resistor than can be changed mechanically.
3
votes
1answer
71 views
How to know whether a potentiometer is a linear potentiometer or audio potentiometer?
In general, how can you tell?
As a specific example, how would I know from looking at the following datasheet? ...
0
votes
2answers
91 views
Continous rotary input?
I need something to work as an input for a rotary device. It must be able to rotate continously, accurate to a degree of rotation, and so that any extra full rotation will have no effect on the input, ...
3
votes
1answer
66 views
Making an adjustable resistance
In my latest circuit, I needed an adjustable resistance to adjust the ratio of a nearby ldr. It looks roughly like this: (btw, I'm not so sure that this schematic is correct. Feel free to fix it :)
...
2
votes
2answers
134 views
The influence of a potentiometer on photo-diode bias
I have a sensor which I have connected to an Arduino via SerialPort to get data readings.
There is a "screw potentiometer" (It's a screw that changes resistance which affects the output voltage).
If ...
1
vote
1answer
53 views
where to connect Potentiometer's pins
I was looking for a circuit to give me 1hz pulse for a digital clock and i found this circuit
Right now I have no idea how to connect potentiometer, i haven't used one before.
I'm trying to make ...
2
votes
1answer
103 views
Help Identifying 5K* Potentiometer
I am currently trying to replace a broken potentiometer in a therapy device ("KMI Hand mentor"). It is a 5k* potentiometer in plastic case/knob and comes in a through-hole version. The length of the ...
0
votes
1answer
59 views
PIC24H POT input to control LED blink delay not linear
Hello I'm using the PIC24H microprocessor and I wrote a simple program that takes input from a POT using analog input which is then set to a modulus value of delay. It does seem to set the delay, but ...
3
votes
3answers
129 views
How to smooth potentiometer values
I have a linear actuator that has a pot in it. I am reading the value of the pot on my uC and I am noticing that the values are fluctuating wildly when the pot is changing (both up and down). The ...
2
votes
1answer
136 views
Building a skin resistance meter (not unlike Scientology type e-meter)
I am trying to build a scientology type e-meter which is based on a Wheatstone bridge with a quad opamp. It is designed to measure the electrical resistance of the skin of a person holding the ...
2
votes
2answers
227 views
Servo Controlled Potentiometer using Rotary Position Sensor
I need digitally controlled potentiometers but I want real pots and not a digital potentiometer chip because I want to integrate this with conventional relatively high voltage circuits like those you ...
1
vote
3answers
129 views
Could a lamp plugged into an outlet be dimmed using a variable resistor?
If you had a variable resistor connected between a lamp and the wall, could it be dimmed with a variable resistor?
Would it be practical, i.e. would it waste much energy? And would it affect both ...
1
vote
2answers
174 views
how to wire up potentiometer to subwoofer
I have a Audio-Taper Potentiometer that I bought from RadioShack and would like to hook it up in-line to my sub woofer so my 5.1 surround sound's bass is not so loud. However, the connections from ...
3
votes
3answers
194 views
“Fine tuning” a potentiometer
I am in the middle of a quandary at work. We have wire feeders that obviously control the feed rate of wire through a welder. We have need of putting these units up out of the way and what I did to ...
4
votes
2answers
226 views
What do you call four 'connected' potentiometers?
I know we have mono potentiometers and stereo potentiometers, when there are two potentiometers connected mechanically. What do you call a potentiometer consisting of four mechanically connected ...
0
votes
1answer
135 views
Nulling Offset Voltage
I am using a ua741 op-amp. My question is, how can I use a potentiometer to null the output offset voltage?
I believe if I'm correct, that output offset voltage means the output voltage provided by ...
-1
votes
1answer
97 views
Changing a Pot's Adjustment Range [duplicate]
I want to put 24 VDC through a 10 k pot but limit the output on the wiper to 2.5 V. Could you advise me what value and where to put the resistors please? There is no load on the circuit as it's just a ...
1
vote
1answer
297 views
how to reduce 24v to 0- 2.5v through a pot
I have a 24v dc supply and I need to give a heater a 0-2.5v variable input. I have a very limited understanding on electronics but I've read here about voltage dividers. I used a 10k pot (and the 2 ...
0
votes
3answers
95 views
cylindrical shaped potentiometer
Do cylindrical potentiometers exist? I'm creating an LED "pen" which will change color corresponding to the position of the twist of the pen.
Imagine one of those pens that retract when you twist ...
5
votes
3answers
453 views
0-10 second on-time with a potentiometer
I would like to make a simple circuit, where the a potentiometer controls a 0 - 10 second on-time.
If the potentiometer is set to min, the on time should be 0 seconds. If the potentiometer is maxed ...
0
votes
1answer
157 views
Digital Potentiometer
Okay so I am definitely not knowledgeable in electronics and need some help involving a digital potentiometer.
I would like to know how I would use the AD5121 digital potmeter.
Lets pretend I had ...
0
votes
1answer
66 views
Can I switch sound like this?
As I game on my xbox on the same screen I have connected my pc, sound is a problem as I only have one set of speakers/headset. Please look at my simple design how how Im thinking of solving the ...
3
votes
3answers
494 views
Using a variable resistor to dim an LED
My question is this: Can I use a variable resistor to control the brightness of an LED?
I was originally planning on using a potentiometer and an MCU to control the brightness with PWM, but that'd be ...
7
votes
2answers
368 views
How do you properly ground a digital pot and an op-amp?
I'm going to take a 5V 500mA power supply and pass it through a digital potentiometer AD5235 and then step it up through an op-amp with a gain 2 to get up to 10V output and put that into voltage based ...
1
vote
2answers
256 views
how to add a motor to a potentiometer?
I have an old piece of analog gear from the 70s and I want to motorize the variable resistors on its panel. I don't want to replace the existing pots with motorized ones but rather to add a motor to ...
3
votes
1answer
251 views
What kind of knob fits a slotted potentiometer shaft?
What I thought was an easy question is more elusive than I suspected. I have a number of potentiometers that have smooth (not knurled) shafts with a slot cut into the end...it looks like a flathead ...
0
votes
3answers
174 views
Can I substitute a mono potentiometer for a stereo one?
I have a PCB for a headphone amp that has a 6-hole pad for a single potentiometer. I've only got 3-pin ones in my box o' parts. Can I substitute the mono pot for the stereo pot, tie the sets of pads ...
1
vote
4answers
356 views
Can I reduce rpm further of a gear motor by using PWM?
I am working on a project where I need to move the object from one point to another in a dead slow speed , The object doesnt weight more than 5 pounds .
I found a DC gear motor with has a RPM of 0.5 ...
3
votes
2answers
128 views
How do I determine if I can safely substitute potentiometers?
I've got a number of audio projects on the workbench, and of course, each of them requires different potentiometers. Instead of waiting for another box o' parts to arrive, can I substitute? What are ...
4
votes
2answers
307 views
What's the difference between linear and audio tapers, and why should I care?
I'm stocking up on a variety of potentiometers to keep on hand for my audio projects, and I'm trying to figure out what to buy.
The projects I'm working on seen to call for either linear & audio ...
0
votes
1answer
45 views
Giving device variable input/setting capabilities
I am working on a device which allows the user to set a certain variable value. So instead of turning something on or off, the user can set a value at some point on a continuum. For example, suppose I ...
1
vote
2answers
251 views
Thumb Wheel Potentiometer
I know that thumb wheel potentiometers are an outdated technology, everything is moving to rotary encoders. The problem I have is that my company has a large number of legacy products. We have ...
-6
votes
1answer
145 views
Will a digital potentiometer work with 230 volts (ac)?
Will a digital potentiometer work in a circuit that uses UK mains power (230vac)?
I want to be able to adjust the voltage digitally.
How could I digitally (or non-manually) control the voltage of a ...
4
votes
3answers
340 views
Using lots of slide potentiometer for computer control
I want to mount a bunch (say 16+) slide potentiometers in a long project box (or other housing that can sit on a desk) that I can use to interact with software on my computer, specifically lighting ...
0
votes
2answers
169 views
Using a POT for ADC
I am using a potentiometer with 5% tolerance as a voltage divider in order to send voltage signals to a microcontroller. The mcu reads the voltage and converts it to digital numbers which is then ...
0
votes
1answer
195 views
Problem Controlling Digital Potentiometer with Micro
I am trying to control a digital potentiometer with a PIC18F14K50 and am having a random problem (potentiometer not remembering correct value) when I power off then back on. The X9313 datasheet states ...
0
votes
0answers
81 views
analog to digital and back again; machine control content
Would members recommend some A/D and ?matching? D/A conversion chips? I'd prefer non-serial devices. 8 bits of resolution would be fine. I want to be able to accept a voltage, decide to use it or ...
1
vote
2answers
237 views
Which component can control the heat of a hot plate?
About this kind of hot plate I was told, quote:
That's very bad because potentiometer needs to emit power which is sufficient part of all heater consumption. In this case we cannot use ...
1
vote
2answers
193 views
Potentiometers: definitions, applications and how to choose?
I've got some newbie questions about potentiometers that I can't seem to find in my reference materials.
I've been doing a lot of experimentation with potentiometers, and frequently run across linear ...
1
vote
2answers
215 views
Replacing a thermal cut-off with a potentiometer
I think this is a pretty basic question but I don't know much about electronics and I could really use some help. I'm trying to modify a hot air popcorn popper to use as a coffee roaster. The popper ...
2
votes
5answers
425 views
What is the size of a normal potentiometer screw hole?
I have a potentiometer that looks like this:
Fig.1
I don't want to solder wire onto the leads. Instead, I want to do something like this:
Fig.2
What is the standard size of the hole that I ...
3
votes
3answers
101 views
Looking for a mechanism similiar to a watch's stem in rotary encoder type form
The watches stem can be pulled out at two different levels to provide two sets of adjustments of the date and time. Is there something like that in the form of a potentiometer or rotary encoder?
0
votes
1answer
312 views
Slowing Down a 12 volt pump with a potentiometer?
I have a small pump hooked up to a 12 volt battery. But as is, it is working too fast and I would like to slow it down. The pump draws 300mA (though it's start up inrush is 3x that).
I am a little ...
1
vote
2answers
200 views
Clickable potentiometer?
I am trying to design a user interface that consists of several knobs which can turn (duh), be momentarily depressed (clicked), and can be backlit, based on whether they have been clicked or not.
I ...
1
vote
2answers
260 views
How does this circuit attenuate high frequencies?
I understand that this circuit could be used as a treble control circuit with high frequency gain occuring when R3 is set so a=b (we'll call this k=0), and high frequency attenuation occuring when R3 ...
10
votes
1answer
293 views
Why aren't log taper pots smooth?
B taper pots are linear, A taper pots are "log", and used for volume controls and such. But the actual specified taper, and what I've measured, is piece-wise linear, not a smooth curve.
Any idea ...
2
votes
3answers
452 views
How to adjust the voltage of this SMPS?
I bought this kind of module for my led light project. Unfortunately it did not come with instructions.
It can be found from eBay with "3.5-28V to 1.25-26V DC-DC Converter Boost Buck Step Up Step ...
2
votes
1answer
1k views
What is the purpose resistors and capacitor in this 555 circuit?
What is the purpose of the capacitor , the resistor , and the variable resistor ?
Do they work like clock pulses for the 555 timer?
-2
votes
2answers
123 views
Advice on fixing laptop volume knob (potentiometer) [closed]
bsd
My laptop's volume knob has been "scratchy" for some time. I have read on The Internets that Deoxit is a good solution for this problem.
Usually, it is advised to take the device apart to apply ...
0
votes
1answer
204 views
Can I use diodes as part of a circuit to multiplex several analog signals?
The micro controller I am using (AVR) only has 1 ADC port, but I have 6 analog peripherals, essentially potentiometers. Since I want to use these 6 different signals on 1 pin, I thought about a design ...
0
votes
2answers
253 views
Rotation sense of a potentiometer
I've been making an audio amplifier, it works well so far after getting the correct components. I'm using a 10K potentiometer with switch for the volume but I've got a problem. The potentiometer ...
