A friend at the phone co. was cleaning a stock room, and found some frequency converters from the early 1970's. Something like 105-127VAC 60Hz to 110-120VAC 30Hz. A quick web search does not reveal their purpose. Anyone know? I'm only aware of 30 Hz for video.
60 Hz to 30 Hz phone company frequency converters; for?
- Thread starter emrr
- Start date
Help Support GroupDIY Audio Forum:
Perhaps ring tone related... according to the WWW 20Hz was standard for NA but the phone co used 30 Hz and other frequencies for selective rings...
JR
JR
