Daniel M Seltzer, 46Columbus, OH

4121149, Oct 17, 1978

Dec 30, 1976

5/755454

Daniel A. Seltzer - Richardson TX

DAS Design Corporation - Dallas TX

H05B 906

323 19

A triac functions as an electronic switch to intermittently connect the AC power circuit to a load, and is directly connected to the output of a 1422 integrated circuit timer which turns the triac on and off according to a controlled cycle. The timer functions as an astable multivibrator which alternately produces high or low output voltages responsive to movement of a control voltage between high and low trigger voltage levels. A charging circuit, including a capacitor and variable resistor, is connected directly between the DC power supply and the timer input to produce an increasing control voltage; and the control voltage is discharged through the timer to produce a decreasing control voltage which determines the duty cycle. The duty cycle is variable by means of a variable resistor in the charging and discharge circuits; and the control includes calibration for the time base.

4776005, Oct 4, 1988

Jul 23, 1987

7/076946

George A. Petriccione - Richardson TX
Daniel A. Seltzer - Dallas TX
Shelly A. Shandley - Lewisville TX

Affiliated Telephone, Inc. - Richardson TX

H04M 157
H04M 354

379142

An interface circuit for a telephone instrument forming part of a character display phone PBX system. The circuit is connected to receive data signals indicative of the condition of the character display and keyboard portions of the instrument, and to store and manage the incoming data and produce a serial RS232 output for communication of the data to a computer or terminal device. The interface enables the use of a computing device to store large amounts of information related to potential calling parties and called parties which may be identified in the display of the telephone instrument and also to associate such information with messages entered into the computer via the keyboard. The overall system thus enables custom answering of a multiplicity of lines of such a character display phone system and use of a single multi-line phone as a messaging center.