Cool, Bob - another devotee of the old phone network! Not only can you play touchtones into a receiver to dial (Radioshack used to make a tone generator to do this), but you can also tap out the pulses on the switch hook of an older phone to emulate rotary dial and call out. My brother used to do this to circumvent the locked rotary dial on an inbound-only phone where he worked, and placed unauthorized calls over the WATS circuit. At four, I taught myself to identify touchtones by ear, but dammit, I never found any job that would pay for this skill.