Aircraft adf with digital frequency display and timer

Claim 2

In an air navigation system, the combination comprising: a. an automatic direction finding receiver for receiving a radio frequency having a continuously tunable local oscillator; b. counter means for counting pulses; c. display means for digitally displaying the count of the counter means; d. a clock pulse generator; e. first logic means for directing a series of pulses to the counter means representative of the local oscillator frequency for a predetermined number of clock pulses whereby the pulses will be counted and the count displayed; f. second logic means for directing selected pulses from the clock pulse generator to the counter whereby time will be displayed; and g. manually operable logic means for selectively disabling the first logic means and enabling the second logic means, or enabling the first logic means and disabling the second logic means.

Claim 3

The combination of claim 1 further characterized by: a. manually operable means for selectively resetting the counter means and for selectively starting the counting means.

Claim 4

enabling the third logic means and disabling the first and second logic means; and h. manually operable start-reset logic means for selectively and alternatively placing the counter in a reset state or in a count state.

Claim 5

enabling the third logic means and disabling the first and second logic means; and h. manually operable start-reset logic means for selectively and alternatively placing the counter in a reset state or in a count state.

Claim 6

In an air navigation system the combination comprising: a. an automatic direction finder system having a continuously tunable receiver for receiving a radio frequency; b. a signal generator for producing time based pulses; c. gating means connected to the continuous tuning wave receiver and the signal generator for passing, in the alternative, the time based pulses or pulses representative of the radio frequency in accordance with a predetermined selection; d. counting means connected to the gating means for counting the pulses passed by the gating means; and e. display means for digitally displaying the count of the counter means.

Claim 7

In an air navigation system the combination comprising: a. an automatic direction finder system having a continuously tunable receiver for receiving a radio frequency; b. a signal generator for producing time based pulses; c. gating means connected to the continuous tuning wave receiver and the signal generator for passing, in the alternative, the time based pulses or pulses representative of the radio frequency in accordance with a predetermined selection; d. counting means connected to the gating means for counting the pulses passed by the gating means; and e. display means for digitally displaying the count of the counter means.

Claim 8

In an air navigation system, the combination of: a. pulse counter means; b. means for digitally displaying the count of the counter means; c. a source of clock pulses; d. first logic means responsive to selected clock pulses for gating pulses representative of the frequency of the local oscillator of an automatic direction finder receiver to the counter means for a predetermined time period; e. second logic means for presetting the counter means to a count representative of the IF frequency of the automatic direction finder receiver; f. third logic means for gating selected clock pulses to the counter means; g. manually operable mode select logic means for selectively and alternatively

Claim 9

In an air navigation system, the combination of: a. pulse counter means; b. means for digitally displaying the count of the counter means; c. a source of clock pulses; d. first logic means responsive to selected clock pulses for gating pulses representative of the frequency of the local oscillator of an automatic direction finder receiver to the counter means for a predetermined time period; e. second logic means for presetting the counter means to a count representative of the IF frequency of the automatic direction finder receiver; f. third logic means for gating selected clock pulses to the counter means; g. manually operable mode select logic means for selectively and alternatively

Claim 10

The combination of claim 4 wherein: the mode select logic means includes a two position switch; and the start-reset logic means includes a push-on, push-off button switch.

Claim 11

In an aircraft navigation system, the combination of: a. clock pulse means for providing a series of time pulses during a time mode and for identifying successive read, reset, preload and count cycles during a frequency mode; b. three decade pulse counters connected in series; c. a binary pulse counter connected in series with the third decade pulse counter; d. a mode gating circuit connected between the clock generator and the first decade pulse counter for gating, alternatively, time based pulses or pulses representative of the local oscillator frequency of an ADF receiver to the decade counters and binary counter in accordance with a predetermined selection of the time mode or the frequency mode, respectively; e. a reset gating circuit for setting the decade pulse counters and the binary pulse counters to zero at the start of the time and frequency modes and during the reset cycle of the frequency mode; f. a preload gating circuit for setting the decade pulse counters to a predetermined count to subtract the IF frequency of the ADF receiver from the count of the decade pulse counters and binary pulse counter during the count cycle of the frequency mode; g. digital display means connected to each of the decade pulse counters and to the binary pulse counter for storing the output signals of the decade pulse counters and the binary pulse counter during a read cycle and digitally displaying the count of each counter; h. a read gating circuit connected to the decade pulse counters and the binary pulse counter for transferring the count of the counters to the respective digital display means during the read cycle of the frequency mode and during the time mode; and i. logic means for converting the second decade pulse counter to a six pulse counter during the time mode.

Claim 12

In an aircraft navigation system, the combination of: a. clock pulse means for providing a series of time pulses during a time mode and for identifying successive read, reset, preload and count cycles during a frequency mode; b. three decade pulse counters connected in series; c. a binary pulse counter connected in series with the third decade pulse counter; d. a mode gating circuit connected between the clock generator and the first decade pulse counter for gating, alternatively, time based pulses or pulses representative of the local oscillator frequency of an ADF receiver to the decade counters and binary counter in accordance with a predetermined selection of the time mode or the frequency mode, respectively; e. a reset gating circuit for setting the decade pulse counters and the binary pulse counters to zero at the start of the time and frequency modes and during the reset cycle of the frequency mode; f. a preload gating circuit for setting the decade pulse counters to a predetermined count to subtract the IF frequency of the ADF receiver from the count of the decade pulse counters and binary pulse counter during the count cycle of the frequency mode; g. digital display means connected to each of the decade pulse counters and to the binary pulse counter for storing the output signals of the decade pulse counters and the binary pulse counter during a read cycle and digitally displaying the count of each counter; h. a read gating circuit connected to the decade pulse counters and the binary pulse counter for transferring the count of the counters to the respective digital display means during the read cycle of the frequency mode and during the time mode; and i. logic means for converting the second decade pulse counter to a six pulse counter during the time mode.