H - Electricity – 04 – M
Patent
H - Electricity
04
M
379/32, 379/59,
H04M 7/00 (2006.01) H04Q 1/45 (2006.01) H04Q 1/453 (2006.01)
Patent
CA 1072695
TELEPHONE TONE SIGNALLING RECEIVER Abstract of the Disclosure A tone receiver, for receiving audio frequency tone signals typically used in telephone signalling, includes a reference frequency generator and a modulator for up-converting audio frequencies. Telephone network tone signalling is up-converted and coupled to a filter including a piezoelectric element. Alternating current signals passing through the filter indicate the presence of a tone signal of a predetermined frequency. Multiple frequency tone signals are detectable using a plurality of modulators and filters, each modulator being supplied with one of a plurality of reference frequencies. In one example, balanced modulation is used with reference frequencies being supplied in the form of square waves. - i -
293272
Northern Telecom Limited
LandOfFree
Telephone tone signalling receiver does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Telephone tone signalling receiver, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Telephone tone signalling receiver will most certainly appreciate the feedback.
Profile ID: LFCA-PAI-O-833087