Lara Grant

TechShop SF! Embroidery Machines and Droid Headphone Control

On my way flying from LGA to SF I lost my iPhone.
I have since become an Android user.
I had an unfinished project making a controller for my iPhone via the charger input, so I needed to make one for my droid instead.

Researching, I came across this post on Hack a Day, which links to a schematic.

Rich Kappmeier’s original post.

Unfortunately the resistance values shown in the schematic don’t register as a 3-button controller by my phone. It’s an AT&T Avail, it seems to just support a single button control.
I may need to try swapping more resistance values, but in the mean time was happy with a one button control.
Would love to have one of these!

Taking a TRRS plug, I wired it up.

I found a couple different schematics, this one worked with my Avail + a resistance chart for the 3-button feature (not supported by the Avail)

TRRS plug wired up

I then thought it would be grand to have a contact switch, using your two fingers. The timing for the clicks to be read by your droid can be tricky and I didn’t want pesky mechanisms to get in my way.

There is a Brother PE770 embroidery machine at the SF TechShop. I took a class and hopped on to make a switch, embroidering a design of nylon thread and conductive thread to make my two contacts.

embroidery process, brown nylon with the silver conductive thread contacts done

love the pattern of the foundation stitching done by the machine

finished outlet design

tips of multimeter touching one side of switch

contact switch

Have your say