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-5
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0answers
69 views

How inductive and capacitive energy is produced [on hold]

How can a power plant produce capacitive and inductive energy? Capacitive is the delay on current in reference to the voltage. And the Inductive is current leading in reference to the voltage. How ...
0
votes
0answers
22 views

Microchip DV102013 Not Recognized by Computer [migrated]

I am attempting to use the DV102013, a multi-touch PCAP by Mircochip, but when I connect it to the computer, there is no sign that the computer recognizes the device. The LED on the device lights up ...
4
votes
0answers
48 views

Water level capacitive probe topology

I'm building a small capacitive water level sensor for a reservoir (16cm tall x 10cm x 7cm). This prototype gives me 10pF on free air and 20~30pF on medium water levels, so its definetively doable (...
1
vote
1answer
65 views

Capacitive Coupling Between Adjacent Conductors

I have been unable to find a definitive answer to my questions after some extensive browsing online. My question involves the coupling between two adjacent conductors (wires, PCB traces, etc) due to ...
-1
votes
1answer
96 views

Heartrate measuring using capacitive touch sensor

I am new here, and I hope someone could help me. So I've read in the datasheet of the capacitive touch sensor ATMEL42QT1011 that we could use it as a heart rate sensor.But what I don't understand is ...
1
vote
2answers
45 views

Simple short range object proximity identification using capacitive sensing

I'm designign a device capable to sense proximity with other identintical devices and communicate that to a central node via bluetooth. The problem I'm trying to solve is showed in figure. So far ...
1
vote
0answers
110 views

Homemade shielding of a wire to a capacitive sensor

I'm using a capacitive sensor CAP1188 with Arduino, connecting 8 of its touch sensor inputs to 8 copper boards that I want to be the actual touch surfaces. The wires to the sensor are quite long (...
-1
votes
1answer
52 views

Capacitive touch switches drop voltage and limits current

Bought two different touch switches/devices to toggle outputs to other devices. I use this on USB power so input is 5V. With use of a powerpack it can handle 2A max. NOTICE: Ask my question here ...
0
votes
1answer
191 views

capacitive switch behind a mirror (silver backing)

I am new to this field, and I would like to DIY a mirror with a hidden capacitive \inductive touch sensor behind it, once touched it will turn on a 12V LED light. I have bought a capacitive switch ...
0
votes
2answers
128 views

Grid is capacitive in the evening

what does this term mean? "the grid in the evening is capacitive"? I work at a company and we are working on integrating a battery storage system on a utility scale for peak shaving of solar. When we ...
-1
votes
1answer
77 views

How to obtain the transfer function of the capacitive sensor?

I want to obtain the transfer function of this capacitive sensor which in the circuit, C is the variable capacitor that transforms displacement to electrical signal and E is the dc voltage source ...
1
vote
1answer
125 views

Convert capacitive touch sensing back to mechanical switches?

Capacitive sensing seems to replace often mechanical switches. Is there a way to convert them back to mechanical switches? Problem at hand is a cooking device with interfaces with the user via the ...
1
vote
1answer
118 views

How does capacitive EEG electrodes measures EEG signals

I have read the following sentences from an article: The effect that there are also charge displacements on the body surface due to brain activity is used for the capacitive measurement of the ...
1
vote
0answers
83 views

MPR121 low sensitivity problem

I bought the Adafruit MPR121 and connected it to a piece of metal which is covered by gaffer tape (no direct touch possible) talking to the MPR121 with the Adafruit library. The baseline/filtered ...
0
votes
1answer
83 views

Capacitive Moisture Sensor - Is AC or DC better/more accurate?

I am looking into making a capacitive moisture sensor. This has been discussed many times already, but I am not sure what is the better option, AC or DC. I want to run this off of a battery, so DC ...
1
vote
1answer
115 views

Which MCU (Atmel) I can use with QTouch library?

Some MCU have QTouch support - # touch channels implemented as a hardware. Is it true that QTouch library was designed only to work with such MCUs? Can I use it with, for example, 'old' ATmega48? Is ...
1
vote
2answers
51 views

Is there any material that obstructs or resists capacitive sensing?

For example, is there any material I can place over a capacitive sensor, or the finger or conductor approaching it, so that the sensor will no longer activate?
2
votes
4answers
262 views

Excessive temperature on cheap soldering iron - will series capacitor fix it?

Soldering iron came in a $14 USD kit off eBay. Lots of neat stuff, but the iron became so hot as to badly damage a DIY Kit. After a 2nd chance w/ the same results, it was hacked, Heating element of ...
0
votes
1answer
59 views

Trigger capacative button

My washing machine is equipped with a capacitive start button. A "button" is marked with paint on the plastic front and on the backside of the panel there is a spring extruding from the control PCB, ...
1
vote
1answer
101 views

What material can I lay over a capacitive touch screen that will still make it work?

So I am trying to build a capacitive touch screen in a table, but since the table is much larger then the touchscreen. I like to put something on top that not only make it easier to clean, but also ...
3
votes
0answers
67 views

Touchscreen Sniper [closed]

I was reading today about how capacitive touch works. This article on the Arduino site mentions that with a 40 Megaohm resistor you could detect an untouched "touch" from possibly 24 inches away. My ...
-1
votes
1answer
85 views

How to calculate inductive and capacitive reactance?

I am studying a project that calculate reactance power. I can measure apparent power, real power and power factor. Therefore I can calculate total reactance power. But I don't know whether it is ...
0
votes
1answer
35 views

How can I interface to a capacitive sensor and measure its value with my Netduino?

I've just bought a rain detector, not realizing it is a capacitive sensor (I had assumed it was going to be resistive, as most are). However, being capacitive means it can be sealed so no electrodes ...
5
votes
3answers
255 views

Making conductive traces for capacitive touchscreens

This is a follow-up to this question I asked years ago. A short summary: I'm using a head pointer (see my linked question for a photo) with a tip made of plastic, thus non-conductive. The shaft is ...
1
vote
1answer
52 views

Capacitive Sensing and Dielectric Coupling

I have a design that uses the MPR121 capacitive sensor. It's a very simple board with 10 "slider electrodes". Standard 2 layer construction with FR4 .063" thick. The board interfaces with a ...
1
vote
1answer
88 views

Need help for calculation of this capacitive power supply

Look at this circuit. It's an almost complete capacitive power supply with necessary part. simulate this circuit – Schematic created using CircuitLab I have trouble calculating: the ...
0
votes
1answer
27 views

capacitive power suplply

i have following doubts about capacitive power supply or transformerless power supply... what will be real power drawn, will it be 230 x (current flowing through C1) or 6 x (current flowing through ...
1
vote
2answers
214 views

How to do capacitance measurement with high frequency oscillator

There are many types of capacitance sensors. I recently come across moisture sensors which measure the dielectric constants of the materials and correlate them to the water content level. It turns out ...
0
votes
1answer
134 views

What is the minimal capacitor (capitor type/size/capacity) needed to fool a capacitive touch screen? [duplicate]

Say I want to provide a device (completely batteryless of course, and detached from any human touch) the capability to immitate a touch on a capacitive screen (Galaxy S6 here). I know I just need some ...
6
votes
10answers
3k views

How to make 1 bit permanent memory circuit?

I would like to make a simple circuit to store or save 1 bit of data. The circuit should be able to remember the state of an LED ( on or off ) even if the supply is disconnected from the circuit. I ...
4
votes
0answers
165 views

What material can I lay over a capacitive touch screen to block its operation, while still allowing me to see it? [closed]

I own a Kindle Voyage and would like to be able to hold it anywhere, not just along the edges, while reading. So I'm looking for a material that's clear to read through, relatively lightweight, and ...
0
votes
1answer
374 views

Simple capacitive proximity/touch sensor problem

I've found one simple schematics for capacitive sensor on electronics-project-design.com, and implemented it as follows: The B? is 9v battery. Sorry for the odd-looking schematics: gschem usability ...
1
vote
1answer
443 views

capacitive sensor and wire length

I'm a newbie and I've been playing with the awesome Adafruit CAP1188 capacitive touch gizmo. As long as I keep the length of the wires from the CAP1188 to my copper sticky pads to a couple of feet, ...
0
votes
3answers
3k views

How do you measure soil moisture using a capacitive sensor?

There are a number of capacitive moisture sensor designs on the internet, which use the insulated copper pads on a PCB.For example: http://zerocharactersleft.blogspot.in/2011/11/pcb-as-capacitive-...
0
votes
1answer
94 views

Capacitive sensing between two copper plates

Is it possible to detect touch event and its position coordinates between two copper plates spaced apart by approximately 6-7 centimeters? The space between plates have to be transparent.
0
votes
1answer
160 views

What sensors can accurately detect size of content in a closed container such as number of pills in a pill box?

I am a DIY enthusiast playing with different sensors and electronics. Recently I've been trying to make a pill box for my grandparents to track their medicine intake. However, I cannot determine ...
3
votes
2answers
118 views

Finding the touching angle on a touch-screen?

I am wondering if it is possible to detect from which direction (or at which angle) a human touches a touchscreen. Imagine something like this: Is there any technology out there (e.g. special ...
0
votes
1answer
108 views

Given the dynamic and static power consumption how does one determine the total power for the capacitive load?

I get that the capacitive load is determined which is also indicated by this question: $$\frac{Power}{Voltage^2 \times frequency} = Capacitive Load$$ However, I am not sure how power (which is ...
3
votes
1answer
177 views

capacitive touch screen

I am currently trying to build a capacitive touch screen. My end goal is to create a giant track pad/keyboard for my computer. Since abnormally large touch screens are quite pricy I have set out to ...
0
votes
1answer
55 views

Are capacitive display(s) capable of measuring what fraction of a finger is touched?

I'm really curious to get an answer for this question. Since I don't know the functioning of a capacitive display and Google didn't help me on this issue, I landed here. :) Are capacitive displays ...
0
votes
1answer
57 views

Feasibility- Flex Capacitive Touchpad

I'm a student(don't know much on Eagle) working on a project where I need a way of multi-touch finger tracking on flexible material. Will flex pcbs work?
0
votes
1answer
282 views

QTouch Matrix ATmega8 issues

After trying a lot on QTouch Matrix for ATmega8,It didn't work for me. So sharing the trouble here. I have taken reference from this beautiful article. Here he had provided a schematic and PCB ...
1
vote
1answer
156 views

What are possible reasons for this not to work

I connected a 5V relay to an Arduino. It then opened and closed the relay, which had on a terminal (doesn't matter which one?) a wire that went to an iPhone' screen (with tin foil at the tip). On the ...
-1
votes
2answers
112 views

Capacitive ECG electrodes and capacitor discharge

I am trying to make ecg electrodes with capacitive coupling. Since my capacitor is only about 10 pF at max and I have to have as low cut-off frequncy as possible, I came up with a circuit like this. ...
4
votes
1answer
270 views

Inrush current limiter - design questions/review

I am considering to use the inrush current limiting circuit that was suggested in this answer. I have a pretty big capacitive load of about 40000uF to charge. Its a buffer for a GSM modem that needs ...
1
vote
1answer
488 views

Capacitor Touch switch with QTouch

I have been working on QTouch Implementation for ATmega32 Micro controller. I have taken reference from here. I'm facing issue with grounding Problem. For debugging process I am displaying the result ...
5
votes
1answer
197 views

Electric shock from laptop due to capacitive coupling?

If a person touches an exposed wire (the wire has a ground-prong) on the 20V side of a power cable while barefoot, I heard that it is possible to receive a shock of higher than 20V due to capacitive ...
2
votes
2answers
696 views

Causes of ringing in a PCB

Im trying to understand the source of ringing at the termination point of a PCB traces before i delve into actually designing a PCB. For example, by 'termination point', I mean a clock signal ...
0
votes
2answers
748 views

Insufficient ground supply on my circuit? Ground capacitive foil

I'm playing with a wireless sensor device (with atmega, xbee, and Capacitive sensor (simple foil)) that works fine with the lab power supply but as soon as I try it with AA batteries stops working. ...
0
votes
2answers
152 views

Capacitive touch directly above LEDs

I'm trying to make a design where the user can run his/her finger directly over a series of 10 LEDs (covered with 1 mm glass), and the LEDs should glow on/off based on the finger's position. I wish ...