I am looking for someone who can build a custom circuit for hire. I''d like to run it off a 12 volt battery, be connected to a POTS phone that's not connected to anything else, and generate a dial tone for lets say five seconds after the handset is picked up.
I just picked up my landline phone to listen to what a dial tone is, and it seems like all I heard was an F and A below middle C together. Sounds like something that could probably be rustled up with the electronics project kit I had as a kid. (I don't remember who made that kit. It was in a box made of actual wood. I don't remember if the components were mounted on plastic or cardboard. The terminals for attaching wires were little springs; you'd just bend 'em and stick the ends of wires between the coils.)
