I'm trying to build for myself a smartphone camera wired trigger over audio input/output port (a.k.a. 3.5 mm jack used for heaphones/headsets). I'm completely lacking electronic engineering skills (only what learned back in school). So here it goes..

There is such 3.5 mm Headset: Accessory Specification, which I think is the go to for what I'm trying to do..

After trying the headset that I have both Volume - and Volume + perform the same task - take a photo, no matter which button you press. Thus from specification it would be either Function B or Function C - doesn't matter much which.

So the questions that I have are:

  1. Can I safely remove buttons (and resistors associated with them) that I don't need in this case from the schematics safely (in this case Function A and Function D buttons, and optionally one of Function B or Function C), leaving with just one button - either Function B or Function C in the schematics?
  2. Can I safely not include both speakers in the schematics?
  3. Can I safely remove the microphone from the schematics or do I have to replace it with a resistor?

Yes, you can.

Yes, you can omit them. Look at handsfree headsets. Same exact thing as headphones except only one speaker.

And maybe. The phone may not recognize a remote is connected if the mic is completely missing. You are essentially making what's known as a quick klick (click) button. Simple and done by many, as well as super cheap commercial versions.

Keep in mind the Wired Audio Headset Specification is for devices to conform to Android Specs. It is required that android devices support the feature, not a requirement that the headset have the feature. Even then, it's just "strongly recommended" that the device support it.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.