I'd like to find a simple way to switch the audio output of my Amazon Echo between its internal speakers and an external audio system. Fortunately, Amazon was gracious enough leave a little cavity at its base.
I was thinking of installing a switched phone connector and a DPDT relay such that the switch inside the phone connector controls the supply of power to the relay: plugging the jack into the connector switches the audio to the external speakers; unplugging it switches to internal.
I could quit here but it bothers me that the relay will likely be energized, consuming 140mW, for days or even weeks at a time.
An impulse relay comes close to solving this, except it transitions on an impulse, not a step. I'd rather not have to deal with the headache of building a differentiator, experimenting with pulse durations, rectifying the output, and fitting it all in a small space...
It seems like a relay that had this behavior built-in should exist, and actually be quite common, but I can't seem find it. Is there a simple way to accomplish this objective?