Tagged Questions

1
vote
2answers
490 views

Sending audio signals to output device through relay

I've created a paper speaker through this tutorial, except instead of conductive thread I used copper tape for the coil. When I hook it up to a device that is known to give off lots of sound, the ...
5
votes
2answers
384 views

Controlling a power strip with a toggle switch. Flight sim design

I am building a cockpit. It will function basically as a flight simulator but for a different game. Mechwarrior online. a Mechpit. Here is my problem. Toggle switch 1 when flipped on turns on the ...
1
vote
1answer
453 views

How can I use audio signal to actuate relay (or close dry contact)?

I have a time clock (prox reader) that has no contact or voltage output - other than a speaker chime. I need to actuate a turnstile on valid time clock swipe (RFID card). I'd hoped I could steal the ...
3
votes
2answers
465 views

Digital Switching for Audio

I want to be able to digitally switch the input of a line-level preamplifier. I was considering using relays to physically connect or disconnect each source to the input of the amp, which would be ...
1
vote
1answer
403 views

Solid State Relay two switch based on headphone audio output to control dc signal

Need to turn on an LED if there is any audio present out of the headphone jack of a cell phone (0.6v peak voltage). If there's no audio, need to turn off led. My plan is to hook up audio signal to the ...
1
vote
2answers
395 views

How can I actuate a relay coil from a headphone jack's internal SPDT?

I want to plug my iPod which in turn supplies power to an external audio amp while sending iPod audio signal to same amp. Is it possible to wire an 1/8" (3.5mm, mini) stereo jack in such a way that ...
2
votes
2answers
341 views

Is there anything better that a SSR when working with audio signals?

I'm using the output of an op amp (LM308) with a low pass filter (R=4700Ohm C= .01 uF if that helps) to control a SSR (D2w203F) which is controlling a string of Christmas lights. I was wondering if ...
1
vote
2answers
456 views

How can I best amplify a signal from my headphone jack to operate a relay 3-32VDC?

I'm working with the following op-amps: LM308AN LM358P UA741CP I want to make a small box that will control the power to any string of christmas lights based off of music that is playing. I would ...
3
votes
4answers
2k views

audio controlled relay circuit

I need a circuit that fires a relay when it detects audio pulses from one channel of an mp3 player. I'm going to record audio pulses in sync with the music to control a motor for mouth movement. Its ...