Abstract: The present invention relates to electric light sources such as may be used in sealed beam lighting units. An electric lamp assembly comprises a sealed envelope containing a light source mounted in a flanged lamp cap. Terminal pins pass through hermetic seals in the cap and support the light source in a predetermined position relative to the cap flange.

Abstract: An improved character reading system that utilizes two separate read devices: a first read device and a second read device in combination with a random access memory for storing each character read by the first read device, a memory control circuit for writing each character into the random access memory, and a comparison logic circuit for comparing each character as read by the second read device with the corresponding character stored in the random access memory. The system also includes a time-out counter for indicating when the last character has been read and a comparison logic timing circuit for controlling the comparison logic and triggering the random access memory read control circuit so as to provide the corresponding character to the comparison logic.

Abstract: In order to provide for a digital data transmitting system of increased security, means are provided to dynamically alter the synchronous compare character between message transmissions. Included in the data communication system are: a character general for programmatically generating a synchronous compare character; a character storage register for storing the character so generated; and circuitry for moving the synchronous character from the storage register to the data transmission circuitry. By dynamically altering the synchronous character between message transmissions, it is possible to substantially enhance the security of the data transmission system.