| 摘要 |
A receiver which may be tuned in a step, slow, or fast tuning mode through operator actuation of up and down tuning switches is disclosed. The counting direction of an up/down counter as well as its counting mode is determined by which of the status of the two switches. Control circuitry responds to the status of the switches to discretely increment or decrement the counter in response to momentary actuation of a switch. The counter is clocked at a slow rate if a switch is continuously actuated for a predetermined time interval and at a high rate if both switches are actuated concurrently.
|
