Abstract: A telephone with a selectable level of sidetone for use in noisy environments. The selectable level of sidetone is achieved by forming a switch-controlled feedback path including a gain setting resistor from the output of a transmit amplifier in a hybrid circuit to a summing node virtual ground at one input of a differential amplifier driving the handset speaker. The summing node is also coupled to the audio output port of the three port hybrid so as to also receive incoming audio signals from the tip and ring lines. A microcontroller having configuration data controls whether the switch is closed and the feedback path exists or the switch is open and no feedback occurs. Lower sidetone or no sidetone is useful in phones used in noisy environments such as factory floors or restaurants.

Abstract: A self-regulating, automatic watering planter comprised of an inner shell and outer shell with a snap-fit engagement to form a reservoir for water between the walls of the inner and outer shells. The inner shell has small holes in the bottom thereof to allow water to enter soil contained in the inner shell. An airtight seal between the inner and outer shells creates a vacuum at the top of the reservoir as the water seeps through the holes and the water level drops. The water in the walls provides hydrostatic pressure that drives the water through the inlet holes. The water stops when the vacuum reaches a sufficient level to counteract the hydrostatic pressure. An air tube coupled to the air space on top of the reservoir and having a hydrophilic polyethylene sensor blocking one end is buried in the soil.

Abstract: A method and apparatus for carrying out synchronous code division multiple access (SCDMA) communication of multiple channels of digital data over a shared transmission media. The system includes modems at remote units and a central unit to receive time division multiplexed digital data arranged into timeslots or channels and uses orthogonal codes to encode each channel of multiple data and spread the energy of each channel data over a frame of data transmitted in the code domain. Spreading the data this way makes the system less susceptible to impulse noise. Frames are synchronized as between remote and central units using a ranging scheme which is also useful in any other system transmitting data by frames in a distributed system where synchronizing the frames as between all units regardless of differences in propagation delays is necessary. Each frame in the SCDMA modulation scheme includes a gap or guardband containing no other data.

Abstract: An RF linear accelerator using CW or low amplitude pulsed RF excitation which can efficiently accelerate charged particles from 0.1 C to relativistic velocities in excess of 0.9 C. A charged particle source feeds charged particles having velocities of about 0.1 C into a first type RF LINAC having a plurality of side coupled resonator cavities each having a drift tube in the middle. The RF length of the cavities is set relative to the velocity of the particles and the RF excitation wavelength such that the particles experience in-phase accelerating E fields in the gaps on either side of the drift tube and are shielded from decelerating E fields while inside the drift tubes. The RF coupling cavities establish sufficient phase change between adjacent resonators such that the particles arrive in the adjacent resonator cavities in synchronization with oscillations in the standing wave therein so as to experience further acceleration. The first RF LINAC accelerates the particles to 0.5 C approximately.

Abstract: A variety of PC card interfaces to interface from many different types of input devices to Personal Digital Assistants or palmtop computers through PCMCIA slots. The disclosed interfaces can receive data in undecoded format from laser based, wand based or CCD based barcode scanning engines, decode the data to alphanumeric characters and pass the decoded data to the PDA via the PCMCIA 68 pin bus. Other PC card based interfaces are also disclosed which can accept input data in the form of ASCII or EBCDIC characters from virtually any type of input device which a standard serial or parallel output or custom output bus and input that data to the PDA through the PCMCIA bus. Some embodiments use programmed general purpose microprocessors to decode undecoded barcode scan data on the PC card. Other embodiments use custom-programmed, commercially available barcode decoding chips to decode incoming undecoded barcode scan data.

Abstract: There is disclosed a variety of PC Card interfaces to interface from many different types of input devices to Personal Digital Assistants or palmtop computers through PCMCIA slots.The disclosed interfaces can receive data in undecoded format from laser based, wand based or CCD based barcode scanning engines, decode the data to alphanumeric characters and pass the decoded data to the PDA via the PCMCIA 68 pin bus. Other PC Card based interfaces are also disclosed which can accept input data in the form of ASCII or EBCDIC characters from virtually any type of input device which a standard serial or parallel output or custom output bus and input that data to the PDA through the PCMCIA bus.