Proportional digital control for radio frequency synthesizers

In a proportional digital control system using binary coded decimal control for tuning radio frequency synthesizers:

• a switching signal control source with reference signal pulse output means [,] for producing a reference signal pulse waveform and an up-down count signal pulse means for producing an up-down count pulse waveform, with a change in count determined by said reference signal pulse waveform and the count direction, whether up or down [count] , determined by phase relation of said up-down count signal pulse waveform to [the signal pulses of] said reference signal pulse [output means] waveform , and means for shifting [signal pulse] the phase of said up-down count signal [means] pulse waveform relative to [the] said reference signal [pulses] pulse waveform ;
• a circuit chain of a plurality of up-down counter to binary coded decimal output circuit units connected to receive directly from said switching signal control source only the two said reference signal [pulses] and the phase shiftable up-down count signal [pulses] pulse waveforms , and with carry over interconnect between adjacent digit locations of said up-down counter circuit units;
• a frequency synthesizer with a BCD input frequency selector control circuit connected to the BCD output of said up-down counter circuit units;
• and a plurality of digit display devices with BCD signal input circuit means connected individually to receive the BCD output signals of the individual up-down counter circuit units of the respective digit locations.