Frequency of 12v halogen transfomer?

Hello everyone.. I would try using a 12v transformer halogen (please see photo) for flyback driver (about 10-30 watts) .But seller sell on Ebay do not know the frequency of 12 vac, so could you help me to know that(frequency of 12 vac out) thank you in advance.

Asked by lam 3 years ago



How do you change the AC frequency?

How do you change the AC frequency that comes out of the wall?

Asked by Comhippy 8 years ago


Can I reduce the frequency of the newsletter ?

Hello all fellow makers ! It seems I can change the frequency of almost any other email sent from Instructables but I can't figure a way to reduce the frequency of the newsletter.  Once a week would be nice.  Is there a way ? Thanks, Guillaume

Posted by aka.guf 3 years ago


Is there an easy way to change the electrical frequency? From 45hz to 60hz?

Is there an easy way to change the electrical frequency? From 45hz to 60hz?

Asked by 8 years ago


frequency filter

I've never designed a filter before and I'm not sure if you can do this. Basically I need a way of filtering out all signal except for signal in the range of 40-150 Hz

Posted by guyfrom7up 9 years ago


Frequency driven speed for chase lights..?

I have some battery operated chase lights (Christmas lights) that I want to wrap around a musical instrument.. When I play a note, I want the frequency of the note to drive the chase light speed. So higher notes will make them chase faster than lower notes.. How can I do this?

Posted by 3DPiper 4 years ago


Help converting 60hz to 50hz

I currently have bought an aquarium pump from the UK and am using it in the United States. I have bought a step up transformer that goes from 110v input to 220v output. The pump works, but is not functioning properly, it loses flow rate over time and gets pretty warm. One thing that I think may be affecting the performance is that the frequency difference between what the pump is rated at and what is supplied here in the US. What would be a cheap ( Thanks!

Posted by brandon3rdstone 5 years ago


Using 433M-Transceiver-Module-E32-TTL-1W-SX1278-SX1276-30dBm-LoRa-Long-Range-433MHz

How do i use  433M-Transceiver-Module-E32-TTL-1W-SX1278-SX1276-30dBm-LoRa-Long-Range-433MHz with arduino uno, like schematics, codes, what is MO, M1 to transfer data as I can not find much about it. Cheers

Posted by laidlow7 9 months ago


designing an LC4/LC5 package for mm-devices using Eagle CAD tools?

Hello every one, Since i am totally new to PCB designing and all these stuff, I want to know few things about Eagle CAD tools I will be designing a Frequency up-donwn converter as a University course project. out of many components selected for this project one of them is as follow. http://www.hittite.com/content/documents/data_sheet/hmc523lc4.pdf i have gone through designing of the LC4 package, i hope it would be fine, still i would like to know how to creat ground of a package, creating outline boundries of package (is it from wire or from rectangle, polygon??) and about symbols inside this package, i am confused about drawing them exactly and connecting them to each other (via wire or net or what??), should they be just symbol or e.g i have to draw even what is inside circuit of a mixer or amplifier etc.. I shall be very much thank for your kind help

Asked by lali2 6 years ago


Arduino + RF to create item/finder?

IDEA 1. I've got the idea to create this kind of project where people nowadays being careless and misplace their item. So to counter this problem, i want to create a device which can detect the object/item within an area/radius of the receiver and transmitter. 2. This is not only for item/object but also can be placed on your children just in case they are away from you thus this device can alert you in sound, sight ( blinking LED ) , and vibration. PROBLEM 1. Is it possible to only use 1 transmitter and receiver? 2. Just in case for future uses, can compass be implanted in this device where it will always shows to the transmitter? 3. Currently programming are very hard for me, where can i get reference for programming this kind of device?

Asked by Isaace11 2 years ago


how to measure frequency in this circuit?

i want to measure the frequency of this flasher circuit but i always get a frequency close to that of the mains. I am using a wall wart. i changed some of the components to speed up the flashing but the frequency reading stayed the same. to check my multimeter i tried measuring the frequency of mains and the joule thief circuit and it looks like my multimeter is good. how should i measure the frequency in this flasher circuit?

Asked by codestroy7 6 years ago


frequency of composite video signal ?

I try to configure a tv / video card on my computer to display input from composite video (yellow plug) input when i choose any of the inputs i still have to set the frequency (above). it should be some fixed standard frequency. what is it for pal b/g ?

Posted by 11010010110 9 years ago


High frequency generator

I want to build a VHF (high frequency) powerfull generator for make an unusual form of lightning. It must produce microwaves 10 - 20 mm. length. Please, write here if you have any information about such generator.

Posted by 012345678910 8 years ago


Arduino High Frequency?

I have an Arduino Duemilanove and was wanting to know how and/or what I need to do to create a high frequency signal. I dont have a set frequency in mind but would rather know how to change it so I can gradually step it up until I get desired results.....Have looked at a lot of stuff on google for how to do this and most refer to a wiring.c file but mine appears to be an updated version to what they have...Anyways any help would be greatly appreciated =)?

Asked by afreeland 7 years ago


What happens when you induce two currents of differing wavelength on the same line? Answered

If I induce two currents of differing wavelengths on a single conductive body, say an iron pipe for example, how can I calculate what the resulting signals wavelength will be? Is it as simple as taking the root mean square of the frequency of the signals? Any ideas for calculating the voltage of the final signal? ------------------------------------------------------------------------------------------------------------------------- Example: Signal 1: 60hz at 100v Signal 2: 75hz at 100v RMS frequency sqrt(((60^2)+(75^2))/2) =  67.9153 ------------------------------------------------------------------------------------------------------------------------- Thanks  a bunch!

Asked by paulcauchon 7 years ago


Measuring oscillation of a multi tool

I have a harbor freight oscillating multitool that is advertised as oscillating between 10k and 20k oscillations per minute. In reality to speed control goes from 0 opm to an unknown value. I’m trying to set the tool to oscillate at 35 Hz. What is the best way to measure the frequency of the tool and set it to 35 Hz?

Posted by rednax718 3 months ago



HOW TO BUILD A FREQUENCY GENERATOR TO REPEL or ATTRACT MOSQUITOES ?

Interested in knowing how to repel mosquitos using a frequency generator. Or can someone guide me in building a frequency generator to attaract mosquitoes (not kidding) so that i can lure them into a trap and kill them. Looking for genuine answers please.

Asked by ramki695 8 years ago


Determining frequency of processor And AVR O.C. ?

So This question has two parts.... i need to measure the frequency of a computer processor.....and an avr microcontroller........ actually i want to know weather it is possible to connect a arduino to a pc's processor through wires or an avr through wires to a secondary system like an arduino which will measure the frequency....... and is it possible to overclock an avr ? if yes , then how can i ?

Asked by _Boltz_ 1 year ago


How to make a frequency converter? 2.4GHz to 600Hz

Greetings, I would like to know how to make a frequency converter. I want to convert the 2.4 GHz from a WiFi transmitter to one fourth or 600Hz which is in the newly freed up white space area for greater range. Anyone know where to find schematics for this, or make schematics? Is the circuit complicated? Thanks

Posted by NeuroPulse 7 years ago


Audio Detector

Is there some type of electrical component which detects high frequency sounds like those mosquito ring tones? I've looked around and seen things which apparently detect high frequency radio waves, but that isn't really what I want (at least I don't think it is). Thanks in advance.

Posted by brickzima 10 years ago


Trying to create a circuit to allow me to adjust the frequency of AC power

I'm trying to design an EM field generator with adjustable frequency. I've got most of it figured out, but I can't seem to find anything about how to create adjustable frequency AC power. I've got two designs I'm working on, one that is DC powered and one that is AC powered, but the best I can do on either ends up with a 60Hz EM field. I'm looking for adjustable frequency, ideally from 0.1Hz to 50kHz, although I'll be pretty happy to even get any range of frequencies at all. The range from 0.1Hz to 500Hz is the most useful and interesting in particular for my purposes, but any help on figuring this out at all would be much appreciated.

Posted by PsychoHazard 7 years ago


How can you generate a signal up to 150 MHz with an AVR?

How could I generate a signal, whose frequency could go up to 150 MHz? I'd like to use an AVR, but how would I do that?

Asked by DemonDomen 9 years ago


Where can I buy a cheep four or eight channel bandpass filter?

I want to build device that will contain LEDs. Each LED will light up to a different frequency. I believe this is the part that i need for this, is it not? if so does anyone know where to get them?

Asked by jmkloz 8 years ago


What radio frequencies will be legal for wireless microphone use in 2012? Answered

Hello, I will be wanting to purchase UHF microphones that comply with the new frequency changes in the UK. I have found many recourses on the internet but none seem to match up? I would be very grateful if someone were to tell me what channels you can operate on (license exept) in 2012. Many Thanks Oscar

Asked by oscarthompson 6 years ago


How to change frequency on RC toy car?

Hi all. My friend and I bought 2 rc toys (1:18 scaled Ferrari F1) just for fun, but they work on same frequency (40.685 MHz) so we can't drive at same time. So i need some suggestions on how to change the frequency on one of them. The transmitter have quartz crystal, but receiver have only coil. I already tried solution "Modding Fisher-Price 72825 Formel Junior Fernlenkflitzer" found on this site, but it didn't work. I ordered quartz crystals from China working on (40.885, 40.985 and 40.285 MHz) and when i changed them in transmitter (one by one) the rc toy still reacted on commands from transmitter. Is there any other way to change frequency? Thanks in advanced.

Asked by dule666 8 years ago


1 watt Frequency Doubled Violet Laser

I want to make a 1 watt violet laser, by using a 1 watt 808 nm laser and channeling the laser through a KTP crystal. Judging from my humble knowledge of second harmonic generation, That should create a 1 watt violet laser beam. Correct?

Posted by Nexoid 7 years ago


How to do an MIDI to frequency conversation without a microcontroller? Answered

Hello! I want to build up an MIDI synthesizer. My main problem is the conversation of the MIDI signal to a frequency. I know it could be done with a microcontroller, but I want to realize it just with resistors, coils, capacitors and non-programmable ICs, because it should be a real only-hardware synthesizer. I do not to interpret all the MIDI control signals, just note on/off. So does anyone has a idea how to realize this conversation just by hardware? Thank you in advance!

Asked by electropeppers 7 years ago


FM Transmitter mod help

Does anybody have any idea how to modify a car FM transmitter for an mp3 player so that it will transmit in frequencies other than the low and high extremes built into it? Also would it somehow be possible to make it transmit to all FM frequencies at the same time? If someone could help me out with this I would really appreciate it.

Posted by kurdiz 9 years ago


555 pwm AND frequency controllable? Answered

Hello, I've been breaking my head on this for a while now, and still couldn't find a correct solution for this. I want to be able to adjust the duty cycle (pulse width) with one potentiometer, and the frequency with another potentiometer, using a 555 timer. Adjusting the frequency shouldn't change the duty cycle! (which is the problem in All of the circuits I find online). This is an example of a circuit I find online, many of the circuits look just like this one (see picture) Now, the problem is that when you increase the resistance of the potentiometer for adjusting the frequency, that makes sure you can never get 0% or 100% duty cycle anymore! or not even close to that. It's because increasing that resistance, also decreases the 'discharging current' of the capacitor, so it will also increase the discharging time when that's not wanted. Without R2 it works perfectly, from 0% to 100% duty-cycle; but with the frequency potentiometer it all gets messed up. It's a little difficult to explain, I'll try it with another example :) To get 0% duty-cycle (or something close to that, like 10%), you'll need to make sure the path for Discharging the capacitor goes near 0Ohm. Increasing the potentiometer for the frequency makes that impossible because it's in series with the capacitor's charging and discharging circuit. So that would also increase the discharging time while I don't want that. When the resistance of the frequency potentiometer increases, the duty-cycle gets variable between just something like 45% and 55% (example) so that's not good. Is there any way do do this? :/ Thanks in advance, Elecotrials

Asked by DELETED_Electorials 6 years ago


Have music control a device with sine wave and frequency? Answered

Whilst I was using  a TENS unit (electric muscle stimulator) and was messing with the frequency and pulse width controls, I thought to myself, "What if I would redesign this device, so that I could plug it into my mp3 player and it control the frequency and pulse width so I could literally feel the music?" After long though, and looking to see if such a device existed (None that I could find.) I came up with nothing. Now my question is, how could I design such a device that would take in standard audio, and give a pulse width and frequency output? I would assume I would use a pulse width modulator (PWM) for the first part, but what about the frequency? And how would I make this as one unit? I am a complete novice at sine waves, frequency, audio, and things in that area, and I find the best way to learn is do a project involving it. So would anyone have an idea how such a device could be designed? Link, circuit diagrams, and tips are all gladly excepted.

Asked by RocketPenguin 4 years ago


555 Timer Calculator

Hi everyone, I was looking around on the internet a while ago for a calculator for 555 timer circuits and couldn't find one that worked very well. Then I set about making my own in a Excel spreadsheet to calculate the frequency and duty cycle for me. I have decided to share it with everyone to help others. It is quite simple. Enter your vaules into the yellow boxes and get your frequency and/or duty cycle from the blue boxes.

Posted by qwertyboy 8 years ago


Need help changing an AC circuits frequency

Alright, so I have a question about an alternating current circuit I was working on.  The wall outlets I'm drawing power from are AC at 120V, and 60 Hz, but I need it to be 120V at between 60 Hz and 1000 Hz.  A variable system would be nice, but I'm not picky.  How would I do this?  Is my only option to convert the power to DC, and then run it through an inverter?  I would like to be able to do this with a small circuit I could build, something that would fit in a project box.  Any ideas?

Posted by Avren5 7 years ago


Is impedance and resistance the same thing in a simple resistor? Answered

Thinking of just this case using an AC current with a frequency of 1k Hz, thru a simple non-inductive resistor. Is the impedance of the resistor the same thing as the resistance measured using DC?  Is it equal to the resistance in value or different altogether? (sentence edited to change inductance to impedance) I think it's the same thing and so equal in value.  Or maybe I've still got a bunch of reading to do.

Asked by Re-design 5 years ago


Frequency of Laser Tag guns

Does anyone know if Laser tag guns use infared LED's emitting at a certain frequency, If so what frequency/range of frequency

Posted by thermoelectric 9 years ago


Variable frequency generator? Answered

I'm looking for a way to build a simple frequency generator that generates high and low frequencies. I was thinking of using a POT to control the frequency range. I looked for it all around but the search didn't help much.

Asked by Misac-kun 5 years ago


Sound Energy?

I would like to know if there is a way to amplify sound waves.  I would also like to know if the frequency of the wave affects the power produced. 

Asked by AlexxSolace 5 years ago


Passive Amplifier Optimized for a Single Frequency

First off, I know next to nothing about acoustics or sound science of any kind.  My idea is to make some sort of passive amplifier, like a horn, that is optimized for a single frequency, I'm thinking about 4KHz.  I have no clue how to go about designing such a thing and all the info I found on google was too complicated for me to understand.  Does anyone has any starting points for me or just general advice/suggestions?  Or, if you're feeling generous and/or really bored, would anyone like to design such a thing for me? Thanks ~Josh

Posted by Josh_Blackburn 11 months ago


How can I use a LM2907 and a microphone to distinguish between two given frequencies; either 5400 Hz or 1900 Hz?

I want to use a LM2907 and a microphone to pick up a frequency (also be able to distinguish between the two frequencies and background noise). I see before me that there will be two outputs. 5V or 0V for "picking up frequency" or "Just background noise" and another output telling whether the microphone picks up the 5400 Hz or the 1900 Hz by 0V or 5V, respectively (the order is not that important when I recon I just can put on an inverter).  What I need to know is the values for my C´s and R´s in the circuit. Can anybody help? I think the Minimum Component Tachometer-circuit will be a good starting point.  The outputs are used for inputs for logic gates.

Asked by Janniche 6 years ago


Can you piggyback RF communications on cellular transmit/receive frequency bands ?

My question is purely hypothetical and there is no immediate plans for any such application. But I was just curious is it possible to make use of the cellular frequency bands (as set out by a country's regulations and by the cellular providers) for some sort of covert type communication other than for voice, data or text types of cellular communications ? Would it be too difficult and complex to develop such an application that uses cellular radio frequencies or could it be done without too much concern for potential interference or the sharing of channels of nearby normal cellular transmissions ? Could such an application be developed without having to cross over many hurdles ? If this covert communications is possible would the cell frequencies used not reach the base stations of the wireless carriers as noise or can a peer to peer communications be possible by passing the base stations ?

Posted by victor43 2 years ago


Questions about computer stereos

Hi! I'm building a portable amplifier from old computer-speakers and I have a couple of questions about them. 1. How do I make the stereo-speakers mono the best way? 2. Is it possible to make low- and high-pass filters to a simple amplifier as the computer ones? I thought I'd connect one bigger speaker (a whopping 5" one!) to amplify the low frequencies and one small to amplify the high frequencies. This would work the best with a 1-channel amp. Thank you in advance, hope you understand what I'm looking for! P.S. Please move the thread if it is in the wrong category, wasn't sure if it suited better under "music" or "tech".

Posted by Henell 10 years ago


Is this derivation RIGHT(physics)? Answered

Hi to whoever is reading this.Yesterday me and my friend derived an expression relating mass of a photon and its frequency .Can anyone tell me if its right?Ps I'm only 15 years old so i may not be right . Here is the link for it: the folder name isPMF.docx and anyone can view it https://drive.google.com/file/d/0B391sIgwIxyvZ196MmtMTFJFa1k/edit?usp=sharing also thank you in advance.

Asked by Strontium 4 years ago


how to make a external pc frequency meter ?

*********** Please be positive and follow instructable's "Be Nice" comment policy . and yes...... i am a newbie to everything (Although it's more than 5 years of ammetuer tinkering)...... so please be positive and don't comment negatively. Thanks A lot. and my english is scrap...... apologies. :)  *********** So  as you can see...... i want to make an external speed meter for my pc ....... and want to display that on a led bar graph . or numerical values on 7 segments.............  all i want to know is that how can i get the pc speed to a microcontroller...........  ? i've got a asus z170 pro gaming mobo....... and i am waiting for 7th gen i3 7100 .........and the mobo also has a external clock generator....... but if i need to get speed through that..... i'd probably need a mcu faster than pc......... so i think the best way to do that is to make a pc program that can recognize pc's current speed........ and send it to a mcu(arduino) through serial connection.......... but now the problem is that i don't know java and c++ that much..... so how to solve this mess ? And can i make same meters for everything else.... like network ram etc. just like a "task manager hardware". And by the way..... i am taking pc building as an art......... and want a stunning stark tech like pc inside a 1.5m x 1.5m man cave. :D 

Asked by _Boltz_ 1 year ago


Body Fat Analyser

Have just been looking at buying some body fat analyser scales, and they are so expensive! £40 for what is essentially a few electronic components and a lookup table seems ridiculous. I think they use an electric pulse and then something to do with how the fat/water whatever resonates or something. As you see I don't have much to go on. Can anyone shed some light on how they measure these things and maybe even post an Instructable. Much appreciated.

Posted by evilad 10 years ago


TV giving off high pitch hum.

Well I recently inherited a old TV it is an SDTV and it is about seven years old. So I decided to test it with my computers osciloscope and using the microphone on it i turned the osciloscope on and there was one constant signal that went up and down about 3 or four KHZ every second or two. But when I muted the TV their was the normal background noise at about 1-7 KHZ but one signal that I found is about 16-17 KHZ and 5.94 DB, and when I turn the TV off it stops and that 16-17 signal disapers. So how do I get rid of this annoying high pitch noise?

Posted by jackillac92 9 years ago


Frequency range? Answered

What frequency range is this project capable of? If I wanted to generate an ultrasonic frequency to discourage critters in my yard, what components would I need to change?

Asked by ColinN8 1 year ago