A variable resistor than can be changed mechanically.

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2
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2answers
119 views

How to adjust linear voltage regulator equivalent?

I'm attempting to build a linear voltage supply. (I'm not touching the mains yet.) My first thought was to use an adjustable linear voltage regulator. Unfortunately, I found that linear voltage ...
1
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0answers
101 views

Buy amplifier to amplify analog 0-5V signal to 0-10V [closed]

I realise the title question has already been answered here in one way or another: Amplify 0 - 3.3V DAC signal to 0 - 10V and Scale 30-50mv signal to 0-5v range I don't understand electronics very ...
0
votes
0answers
36 views

Automatically control EQ and Volume on audio signal

I am trying to control an audio signal with a microcontroller. I would use digital pots but seeing as I need 250k ohms, 300k ohms, or 500k ohms, at LEAST 256 taps, and volatile memory, there don't ...
0
votes
3answers
40 views

How can I evaluate a potentiometer susceptibility to change?

I have a usage case where I would like a potentiometer for controlling the charge going to a lead-acid battery via a IC. It would be susceptible to some (although not extreme) vibration, such people ...
8
votes
2answers
896 views

Potentiometers, little piece sticks off?

I'm not electronics savvy and am a complete newbie. So I'm in the middle of a project and am trying to stick a potentiometer through an aluminum casing and I placed a 1/16" piece of rubber between the ...
0
votes
1answer
28 views

Where would be the best spot to put a logarithmic volume control on this TPA3122 audio amp?

I'd like to add a volume control to the following circuit (a 2x15W Class-D Stereo Power Amp Kit). The schematic below is an image clipped from a PDF I found describing it. This'll be being driven ...
0
votes
3answers
71 views

Newbie question: How do pots limit current?

From my understanding, a series circuit has a constant current, and when resistance is placed in the circuit it is voltage that changes across the resistors and not current. Potentiometers, from ...
0
votes
4answers
61 views

How to convert 10K Pot raw output ADC data to voltage and resistance from arduino uno?

I have a simple and basic question. I am using Arduino uno to read the output from a 10K potentiometer. I understand that Uno uses a 10 bit ADC, therefore it can display outputs from 0 as 0V to 1024 ...
0
votes
2answers
52 views

Can a malfunctioning relay in an amp cause or allow a speaker to crackle when turning the vol potentiometer? [closed]

Ok, so this question has several layers, I admit it. I recently acquired a Lepai 2020A+ amp. It is, I believe, the latest version PCB because it has the two relays for speaker protection instead of ...
0
votes
1answer
57 views

Why does POT cause current to divert?

I have a pretty basic question. I put this little thing together but I don't understand why the POT is causing this result. When powered, if the POT isn't fully open. LED 1 is bright and LED 2 is ...
0
votes
1answer
88 views

Changing potentiometer from a gaming steering wheel

I have Logitech's vibration feedback wheel which has a rotation of 270 degrees. I am considering changing its potentiometer so it can rotate more (900 degrees or 1000 degrees maybe). What ...
0
votes
1answer
44 views

Bi-Directional Rheostat/Potentiometer

is there any known type of device will do the following: [I have read the bi-directional potentiomenters posting LINK but I just joined and can not reply to that posting. I am looking for a rotation ...
0
votes
1answer
77 views

Calculating feedback resistors for op-amp based voltage regulator

I need to design a voltage regulator with an output range of 20-25V. I managed to re-create this ciruit from a course, but I'm stuck on calculating resistor values. These are the formulas I'm given ...
1
vote
3answers
66 views

Is it reasonable for a potentiometer to have a minimum of 1.3Ω?

I purchased a 25Ω linear potentiometer, and found that the minimum resistance is 1.3Ω 0.9Ω. I expected that the minimum would be closer to 0Ω. Is this typical? Should I return the potentiometer as ...
0
votes
0answers
47 views

How can I add a resistor in parallel to a rheostat while keeping it linear?

I have a 25Ω linear potentiometer wired as a rheostat. I would like a range closer to 5Ω, so I added two 10Ω resistors in parallel. This gives me a range of 0 to 4.16Ω which is just fine, but the ...
2
votes
2answers
116 views

Can I use an op-amp in voltage follower configuration as variable voltage power supply?

I see that this works in theory, but I my gut feeling says there is a drawback or caveat of which I'm not aware. Basically what I want to achieve is described best by the circuit diagram below. ...
0
votes
1answer
37 views

Looking for a high temperature potentiometer [closed]

Does anyone know of any potentiometers that are rated up to 500 degrees F?
0
votes
1answer
61 views

Dual Dc regulated voltage circuit design

I'm working on my term project which is designing a dual DC regulated voltage that gives a DC voltage between +or-ve 3 to +or-ve 15. I have completed the testing for positive DC output part, but I ...
0
votes
0answers
34 views

Rheostat and how ohms affect them

I have a two welding machines with the same problem. The rheostats, Ohmite 1.5Ω, 5.77 amps, are damaged. The replacement cost from manufacturer are $100 each. After searching on ebay I found some ...
0
votes
2answers
56 views

How to regulate voltage into two variable outputs?

I'm thinking of building a control voltage generator for a synthesizer. Basically I want to control two pitch control voltages with variable resistors, something like this: R1 needs to control only ...
0
votes
2answers
51 views

Potentiometer with No Minimum Resistance

I'm looking to create a variable current regulator with the LM317 using 1-turn pots. I know that I am going to need to have a resistance of 1.25 Ohms to have a current of 1A, which I want to be my ...
0
votes
1answer
106 views

Use Potentiometer to change frequency in FM Radio Transmitter

I know that in most circuits you use a tank circuit consisting of an inductor and variable capacitor in parallel to generate different frequencies like this one. However since most cheap trimmer caps ...
0
votes
1answer
67 views

DIY Photobooth: LED puck lights potentiometer suggestions

I'm building a Raspberry Pi powered photobooth, and want to add some lighting. I purchased this set of led puck lights, and would love to control their intensity from the Raspberry Pi, instead of the ...
-1
votes
3answers
74 views

Calculate resistors value in voltage divider

I have the following voltage divider circuit with a potentiomenter, and I need to find the value of the resistors. simulate this circuit – Schematic created using CircuitLab How can I ...
0
votes
0answers
68 views

Circuit with “output” resistance as a linear function of “input” resistance

TLDR: How do I make a 6.8kΩ to 20.0kΩ potentiometer look like a 10.5Ω to 19.7kΩ potentiometer when presented with 3.3 volts? I'd like to make a mod for a MIDI controller. Through some probing I ...
1
vote
0answers
62 views

Will this potentiometer control this led strip?

So first off I'd just like to say i know absolutely nothing about electronics. I want to add some lights to my computer case, will this work as a dimmer? 500K 1/2W Linear Taper Potentiometer White ...
0
votes
1answer
87 views

How to offset input voltage of any op amp

There are some op amps that allow nulling of input offset voltage by provding decidcated inputs where, typically, a potentiometer is connected for the offset correction. My question is that if a op ...
1
vote
0answers
33 views

Will my potentiometer provide enough amperage for my h bridge?

I am sending pwm requests to my H-bridge from an arduino. Each pwm signal is a precise so I need to have the h bridge drive it by that specific amount. I want to use 5V for the h bridge supply, so i ...
0
votes
2answers
161 views

How do I use a 5 pin potentiometer?

I have a 5 pin trim pot I desoldered from an old board. I am assuming maybe it is a dual gang poteniometer or something with a common ground pin. Does anyone have any ideas what the actual pinouts ...
4
votes
3answers
183 views

Simple ADC alternative by using a capacitor and digital Arduino pin

I'd like to measure a dozen potentiometers with an Arduino UNO. Unfortunately, the UNO only has 6 analog pins, but it does have about a dozen digital pins. Could I effectively measure an analog value ...
0
votes
1answer
66 views

DC motor as a generator as a torque limiter?

Is it possible to use a DC motor as a generator to regulate applied mechanical torque? A hypothetical situation: I have a DC motor acting as a generator attached to the ceiling. The motor shaft has ...
0
votes
1answer
88 views

Operational amplifier with potentiometer

Given an op-amp circuit with the shown potentiometer. How does one come up with the following gain equation? Also, when the potentiometer is turned up halfway, why is R3 6.12K, instead of 1.12k ...
19
votes
4answers
2k views

Do ‘wiperless’ potentiometers exist?

Potentiometers are renowned for wearing out (at least in my experience); the little wiper eventually just wears its contact and nolonger has a firm electrical connection. For an audio device, this can ...
0
votes
3answers
119 views

Controlling the power from a 9V battery with a potentiometer

I'm working on a project where I'm powering an LCD screen backlight via a 9V battery. As it is currently, I'm powering the LCD via a 9V battery. This works great, but I'd like to have the ability to ...
2
votes
3answers
496 views

3 leg potentiometer - what's the 3rd leg for?

In a potentiometer, I often see the 3rd leg connected to ground. I understand exactly what a potentiometer is physically (a wiper along a log or linear resistance), but I don't understand the benefit ...
-1
votes
1answer
90 views

Do potentiometers exist that include DPDT switches at the limits?

Do potentiometer packages exist that include 2 double-pole double-throw switches, one of which is switched at the lower limit, the other switched at the upper limit? (Preferably with tactile clicks.) ...
1
vote
1answer
120 views

Controlling fan speed with a rheostat

I just got a rheostat from radio shack to connect to my homemade stir plate. The rheostat looks like: (from here) My question is, how do I set it up? I want to use it to vary the fan speed. I am ...
0
votes
1answer
157 views

How to shift resistance range of Linear Potentiometers by X ohms in the Positive or Negative direction?

For example, I have a 10k ohm (linear) Thumbwheel Potentiometer. This POT will produce values from 0 to 10k when reading its resistance. Positive Shift How do I shift resistance range values by X ...
1
vote
2answers
106 views

Explanation for super-sensitive loose contact inside potentiometer?

Symptom I have a mixing console, where one 6-pin stereo pot is errartic. When I turn it all the way down I sometimes can still hear the left channel at full volume. Explanation The circuit is a ...
1
vote
2answers
61 views

Hooking up an 8x8 LED board

I recently bought this 8x8 LED board from geeetech which came with this datasheet. I'm new to programming so I bought this board to "figure it out" but now I'm running into issues I don't understand. ...
0
votes
0answers
67 views

Using capacitors to control the speed of a relay loop

Background: In my autoshop class at school we are required to make a circuit that uses relays. When one relay comes on the other one shuts off and it creates a loop in which they switch really ...
1
vote
1answer
66 views

Could I add a potentiometer to a dremel? [closed]

I bought a cord Dremel a while back for some of my personal projects and it seems to speed up after a minute and the rotary bit I like begins to jump and chips pieces away. I haven't sliced the cord ...
0
votes
3answers
146 views

Potentiometer - How?

I bought a 5m LED strip from Ebay and connected it to 12V 1.5Amps. I am a starter in engineering. What kind of potentiometer do I need to use to lower or increase the brightness? How many Ohms do I ...
2
votes
1answer
88 views

Maximum rotation speed for a potentiometer?

After a slight purchasing mishap, I am to end up with an encoder whose max RPM is too low for the application for which it is to be used. To achieve roughly the same purpose (that is, sensing of an ...
4
votes
4answers
1k views

Circuit for a coarse and fine setting potentiometer?

I've tried to find a circuit for a coarse and fine adjustment (two potentiometers) voltage divider, but I don't understand it and/or they don't have a linear response. Problem: I want to have an ...
0
votes
2answers
194 views

How to connect this potentiometer to this PCB?

How am I supposed to connect this potentiometer to the PCB?
0
votes
1answer
181 views

Arduino analog input higher than reference but lower than 5v [duplicate]

I'm going to use a very precise potentiometer that can measure angles from 0 to 3600 degrees (10 rounds), but I only need the first 180 degrees or so in this project and I need it to be more precise ...
0
votes
0answers
86 views

360 dual-wiper potentiometers

http://www.edn.com/design/components-and-packaging/4405828/Rotary-encoder-with-absolute-readout-offers-high-resolution-and-low-cost ^ That's the synopsis of what I'm looking for. I have a bunch of ...
0
votes
0answers
43 views

Help with Op-Amp project

I have an Op-Amp project, and im stuck on the last part of it; I was wondering if anyone would be able to help; http://imgur.com/GdEWKMN (project outline) http://imgur.com/FVPEr4C (Part A solution) ...
0
votes
1answer
117 views

Help converting analog potentiometer to digital

I have a 3 dial motor control assembly that is using 3 potentiometers to control 3 independent 110v motors speed. The label on the pots read TO50K 1339 (first O has a "S" like shape inside). I have ...