Telephonic communications – With check operated control – Fraud or interference prevention
Patent
1988-07-01
1989-04-11
Lev, Robert
Telephonic communications
With check operated control
Fraud or interference prevention
379155, H04M 1700
Patent
active
048213136
ABSTRACT:
A ground detect circuit for use in telephone paystation consisting of a comparator circuit which compares the voltage across a telephone transmitter included in the paystation to prevent users from fraudulent use of the instrument by grounding the handset transmitter to signal the central office that initial rate deposit has been made when in fact it has not. The ground detect circuit upon detecting the presence of ground at the transmitter generates a signal which can be utilized to disable an associated calling device.
REFERENCES:
patent: 2084121 (1937-06-01), Anderson et al.
patent: 2684997 (1954-07-01), Thompson
patent: 2765366 (1956-10-01), Holden
patent: 3794783 (1974-02-01), Radu
patent: 3863036 (1975-01-01), McCrudden
patent: 3890468 (1975-06-01), Burns et al.
patent: 4124774 (1978-11-01), Zarouni
patent: 4136262 (1979-01-01), Clark, Jr.
patent: 4429183 (1984-01-01), Nemecseil et al.
patent: 4567325 (1986-01-01), Crouch et al.
patent: 4625078 (1986-11-01), Crouch et al.
patent: 4759054 (1988-07-01), Mellon
Black Robert J.
Lev Robert
Palco Telecom Inc.
LandOfFree
Paystation transmitter ground detect circuitry does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Paystation transmitter ground detect circuitry, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Paystation transmitter ground detect circuitry will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-672341