Alphanumeric station display circuit for AM-FM radio - converts oscillator frequency into bit pattern which is compared with stored patterns for generating visual symbols

摘要

The radio receiver oscillator frequency present during or after tuning is converted into a digital bit pattern and compared by a microprocessor with the content of all programmed storage locations. When the pattern coincides with the content of one of them, a triggering signal is generated. The trigger causes the content of another store to be applied to a character generator which generates signal trains which are converted into alphanumerical symbols by a following opto-electronic display unit.