Abstract: A support assembly for supporting two poppel-type actuation switches at a housing, such as a radiotelephone handset housing. The actuation switches are positioned beneath a support body of the support assembly and maintained in a desired orientation relative to such support body by pawl arms which extend beneath the support body. Post members extend beneath the support body to abut against membranes of the respective actuation switches. The support body is affixed to the housing by way of retaining arms positioned to extend beneath the support body midway along the length thereof while permitting limited pivotal movement about rocker arms positioned at sides of the support body responsive to twisting moments applied to the support body. The twisting moments applied to the support body are transmitted to the poppel-type switches by way of the post members form the actuation forces to actuate the poppel-type switches supported thereat.
Abstract: The battery pack retention apparatus, described herein, is an injection molded part. The injection molded part includes a rear housing (200) for a radiotelephone (100), two rails (201, 203) for a battery pack (101) to slide along and six guide bars (207, 209, 211, 213, 215, 217) for retaining the battery pack (101) on the radiotelephone (100). Four of the six guide bars are the compliance-type. The compliance-type guide bars (207, 211, 213, 217) have a U-shape and are coupled to the rails. A channel (401) is cored out from the rails under the compliance-type guide bars to allow for deflection of the guide bars. Deflection is caused by the bullets (409) of the battery pack (101) when the battery pack (101) is fully inserted. The deflection(y) of the guide bars provides a calculated force upon the battery pack (101). This calculated force ensures a high quality electrical connection between the contacts of the battery pack and the contacts of the radiotelephone.
Type:
Grant
Filed:
September 20, 1993
Date of Patent:
May 3, 1994
Assignee:
Motorola, Inc.
Inventors:
Michael L. Shababy, Timothy P. McCormick
Abstract: The bidirectional clocking apparatus provides automatic sensing of whether a reference clock being generated by another circuit needs to be divided down to a lower frequency. If this is true, the clock is divided down to a lower frequency and sent out to other circuits requiring the lower frequency clock. If the lower frequency clock is already generated from another circuit, the apparatus accepts this clock for use by other circuits. Only one terminal is required for either sourcing or accepting this lower frequency clock signal.
Type:
Grant
Filed:
October 16, 1992
Date of Patent:
April 5, 1994
Assignee:
Motorola, Inc.
Inventors:
David M. Hess, John J. Janssen, Michael W. Houghton
Abstract: A method of and apparatus for compensating a received signal's phase compensates for the distortion caused by the asymmetrical characteristics of a voltage limiter. This compensation allows the received signal to be sampled at the positive and negative zero-crossings reducing the requirements of a local oscillator in a radiotelephone system. First, the phase of the received signal is sampled at the positive and negative zero-crossings, forming a corresponding positive-crossing and a negative-crossing phase value for the received signal. Second, the negative-crossing and positive-crossing phase values are combined, forming a first difference signal. Third, an estimated error signal is formed using the first difference signal. Fourth, the estimated error signal is combined with the positive or negative zero-crossing phase signals, substantially eliminating the asymmetrical distortion.
Type:
Grant
Filed:
March 26, 1992
Date of Patent:
March 29, 1994
Assignee:
Motorola, Inc.
Inventors:
Christopher P. LaRosa, Michael J. Carney
Abstract: The present patent application discusses a frequency translation apparatus for altering the effective frequency of the phase information of an input signal (115). The input signal (115) has a first phase (.theta.(t)) and a first frequency (f.sub.i). The phase of the input signal is extracted and digitized at a second frequency (f.sub.o), forming a second N-bit digital phase signal (.theta.'(t))(311). The frequency translation apparatus generates a third digital phase signal (319) which approximates the difference between .theta.(t) and .theta.'(t). Then, the frequency translation apparatus combines the second digital phase signal and the third digital phase signal, forming a fourth digital phase signal (307) substantially approximating the first phase signal.
Type:
Grant
Filed:
December 13, 1991
Date of Patent:
February 22, 1994
Assignee:
Motorola, Inc.
Inventors:
Christopher P. LaRosa, Michael J. Carney
Abstract: A transmitter (604) of a TDMA cellular telephone (600) includes power control circuitry (100) comprised of variable gain stage (104), mixer (106), bandpass filter (109), RF amplifier (110), and directional coupler (112) in a forward path, and two detectors (116 and 117), four A/D converters (118, 119, 121 and 123), digital controller (120), and D/A converter (126) in a feedback path. In operation, the variable gain stage (104) is responsive to a gain control signal AOCCNT (128) for adjusting a modulated IF signal, which is then mixed in mixer (106) with an RF reference signal to produce the transmit RF signal. The temperature and supply voltage are sampled by controller (120) at the beginning of each time slot. Adjustments in the gain control signal (128) dictated by the sampled temperature and supply voltage are made by controller (120) in each time slot prior to keying the RF amplifier (110).
Type:
Grant
Filed:
July 22, 1991
Date of Patent:
February 15, 1994
Assignee:
Motorola, Inc.
Inventors:
Gregory P. Wilson, Donald B. Lemersal, Jr., Rashid M. Osmani, Dale G. Schwent, John C. Johnson