Electronic selection bingo game unit

Abstract

The invention relates to a selection intersection selecting unit for a bingo game. There are 75 unique selection intersections in a bingo game, and this unit permits any one of the intersections to be selected with equal probability. The unit consists of an electronic circuit including a 5 .times. 15 switch matrix. The circuit further consists of a clock circuit means with a low frequency and a high frequency output, and a counter circuit driven by the output. The low frequency output is much greater than 75 c.p.s. The counter circuit drives the switch matrix, and the high frequency output is applied to the counter only during a low output of the matrix. The counter has two sets of outputs, one set containing 5 outputs and the other 15, and each set is connected to a different axis of the matrix. Thus, after each count, a different intersection of the matrix is selected and removed. The remaining intersections will then also be selectable with equal probability.

Description

BACKGROUND OF THE INVENTION

The present invention relates to a bingo game unit making possible selection from among 75 unique selection intersections with equal probability by utilizing electronic circuit means.

In units which have been in use heretofore for bingo, adjustment of the unit itself is difficult because of rocking, etc. when it is used on board a boat, etc. Furthermore, such units have defects in that the balls used for selection have different weights, making it difficult to obtain a set of 75 balls yielding equal probability of selection.

The object of the present invention is to overcome the above-mentioned defects and to provide a unit most appropriate for the bingo game which is compact and requiring no adjustment, and is to obtain a bingo game unit including an electronic clock circuit including a minimum time control circuit capable of controlling the minimum operation time of a selection start switch and two clock circuits. A high frequency clock circuit and a low frequency clock circuit are provided, both having frequencies sufficiently higher than 75 c.p.s.. A counter circuit is driven by said electronic clock circuit and forms 75 unique selection intersections, while a switch matrix circuit is driven by said counter circuit and has 75 intersection points equipped with 75 electromechanical switches arranged in cartesian co-ordinate form corresponding to selection intersections numbered from 1 through 75. Visual display units corresponding to said electromechanical switches in a one to one ratio are provided with a board consisting of the 75 visual display units arranged in the system of cartesian coordinates equipped with additional switches mechanically interlocked with said electromechanical switches, respectively, and having such a characteristic which allows for removal of (75-M) selection intersections already selected and memory of removed selection intersections by means of the position of the abovementioned electromechanical switches. A feedback circuit is driven by said switch matrix circuit and provides a feedback control signal to the aforesaid electronic clock circuit in order to select the output of the abovesaid low frequency clock circuit as the output of the abovesaid electronic clock circuit and to allow selection of one of the selection intersections when the feedback control signal is 1, and to select the output of the abovesaid high frequency clock circuit as the output of the abovesaid electronic clock circuit when the feedback control signal is 0, indicating memory of a previously removed selection intersection, arranged such that the probability of selecting any one selection intersection from among M remaining selection intersections is essentially 1/M. The selected intersection is indicated by means of the abovesaid visual display units and after operation of the switch associated with the selected intersection of the switch matrix circuit the visual indication is removed and the memory of the removed selection intersection is displayed on the board of the visual display units mentioned above, and the system is further arranged such that the (75-M) selection intersections already removed may not be selected again.

DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the persent invention will be described hereunder referring to the attached drawings in which:

FIG. 1 is a perspective view which shows the external appearance of the main part H of bingo game unit embodying the principles of the present invention;

FIG. 2 is the main circuit diagram which shows an embodiment of the main part H;

FIG. 3 is a timing signal diagram of the outputs of each principal circuit which occur in the case of performing selection using the main part H;

FIG. 4a is a circuit diagram which shows the connection between the displaying board and electromechanical switches;

FIG. 4b is a perspective view of the displaying board;

FIG. 5 is an explanatory view which shows the audio unit connected to the main part H;

FIG. 6 is a main circuit diagram including the audio circuit and the initializing circuit.

DESCRIPTION OF THE EMBODIMENTS SHOWN HEREIN

FIG. 1 shows the external appearance of the main part H of the unit which is formed in almost the shape of a rectangular parallelepiped in which only the front surface 1 is somewhat inclined from the bottom surface 2 towards the upper surface 3. Located on the front surface 1 is the selection start switch 4 and a power supply switch 5. Located on the upper surface 3 are the 75 intersection points I1 through I75 arranged in cartesian coordinate form consisting of 5 columns and 15 rows where each of the five columns corresponds to one of the five characters of the word "BINGO," and each intersection point contains an electromechanical switch, S1 through S75, and also a visual indicator unit 6 consisting of 5 lamps LX1 through LX5 forming a coordinate axis 7 and 15 lamps LY1 through LY15, forming a coordinate axis 8. Thus, the visual indicator unit 6 indicates intersection points with one to one correspondence. The visual indicator unit 6 may have such a construction where one lamp is provided at each and every intersection point, or light emitting diodes (LED) may be used in place of lamps. When light emitting diodes are used at each and every intersection point I1 through I75, diodes D1 through D75 may be omitted. (See FIG. 2 and FIG. 6.)

FIG. 4b shows a visual display board 11. Board 11 is arranged in the system of cartesian coordinates and contains 75 numbered visual display units DS1 through DS75, and consists of a connector 13 containing 75 actuating terminals and one common terminal in addition to a power cord 14. Connector 13 is coupled with a mating connector 12 which is connected to supplementary switches aS1 through aS75 which are mechanically interlocked with electromechanical switches S1 through S75 (See FIG. 4a).

The mating connector 12 and supplementary switches aS1 through aS75 are contained in the main part H of the unit. Accordingly, when a selection intersection is selected, one of the electromechanical switches S1 through S75 is switched "OFF" and the corresponding supplementary switch is switched "ON," thus lighting the corresponding visual display unit. It is unnecessary to point out that the switches S1 through S75 and supplementary switches aS1 through aS75 may be so constructed so as to obtain interlocking movement so that the visual display units are turned off in the reverse manner. One lamp is used in the present embodiment for each of the visual display units DS1 through DS75 respectively.

On the front surface of board 11 the lamps are arranged behind a coloured glass surface. FIG. 2 shows the principal circuit of the main part H of the unit which is an embodiment of the present invention and is capable of selecting from among 75 unique selection intersections, in which E1 is the electronic clock circuit whose output is connected to the counter circuit CO2 and further to the switch matrix circuit M3 and the feedback circuit F4 successively, the feedback circuit F4 being connected back to the electronic clock circuit E1. The main circuit is activated by an input control signal 15 from the selection start switch 4 for the purpose of automatically selecting one of the selection intersections, and the selection operation is made possible by means of the feedback control signal 16.

The object of the two clock circuits, A and B is to provide a unit time signal for the electronic clock circuit E1 to drive the counter circuit CO2, and the low frequency clock circuit A consists of an astable multivibrator circuit where the duty cycle and frequency F.sub.A are determined at fixed values by selection of time constants t.sub.A1 and t.sub.A2. In this embodiment, F.sub.A is a square wave at 1000 c.p.s.

The high frequency clock circuit B also consists of an astable multivibrator similar to clock circuit A where duty cycle and frequency F.sub.B are determined at fixed values by selection of time constants t.sub.B1 and t.sub.B2. Since the output Bo of clock circuit B is inhibited by a misselection prevention circuit ER11 during the time delay t.sub.D =1/F.sub.B, the frequency F.sub.B is obtained as F.sub.B >2.times.(75+5).times. 1000=160,000 c.p.s. Furthermore, both frequencies F.sub.A and F.sub.B are sufficiently larger than 75. In other words, even if any number of selection intersections or all 75 selection intersections are removed, it is feasible to obtain a series of nondeleted selection intersections during a single cycle having such a characteristic that memory is accomplished by means of electromechanical switches S1 through S75 by setting the relationship between frequencies F.sub.A and F.sub.B such that 80 cycles of the squarewave output of clock circuit B fall within P (i.e. the negative pulse width of the squarewave output of clock circuit A). (See FIG. 3). Connected to clock circuits A and B is selection circuit 9 which has the purpose of selecting between Ao or Bo or neither by means of input control signal 15 and the predetermined feedback control signal 16 and which consists of nand gates N15, N16 and N17.

When the output of the acquisition request memory circuit ME is 0, the outputs of nand gates N15 and N17 are inhibited. That is, the output of nand gate N17 is 1 during this period. While the output of the acquisition request memory circuit ME is 1 and the output across resistor R21 is 1, the output Ao of clock circuit A is selected as the input of nand gate N15. Furthermore, when the output Ao is 1, the output of nand gate N15 is O, and when the output Ao is 0, the output of nand gate N15 is 1. During this period, (when Ao = o), the output of nand gate N16 is inhibited or 1.

During times when the output of the acquisition request memory circuit ME is 1 and the output of resistor R21 is 0 and after an inhibit period t.sub.D =1/F.sub.B by means of the misselection prevention circuit ER11 following the 1 to 0 transition of Ao, the output Bo of clock circuit B is selected as the output of nand gate N16. When the output Bo is 1, the output of nand gate N16 is 0, and when the output Bo is 0, the output of nand gate N16 is 1. During this period, the output of nand gate N15 is 1. As described above, nand gate N17 responds only when the output of either nand gate N15 or N16 is 0. Furthermore, it is unnecessary to point out that the output of nand gate N17 is in phase with the output Ao or Bo of either clock circuit A or B respectively. It should be noted that the outputs Ao and Bo have no particular phase relationship at any time. That is, outputs Ao and Bo are asynchronous.

The misselection prevention circuit ER11 consists of capacitor C3 connected from the output Ao to one input of nand gate N16. Capacitor C3 is discharged beginning when the output Ao makes a 1 to 0 transition and before the output of nand gate N16 could potentially make a 1 to 0 transition. In other words, the object of this circuit is to prohibit selection of output Bo of clock circuit B as the output of nand gate N17 during the delay time of approximately t.sub.D =1/F.sub.B.

A pulse forming circuit PS10 is connected to the output of nand gate N15 through capacitor C2 coupled to the input of inverter 18, the output of which is connected to the input of the acquisition circuit AQ7. When the output Ao of clock circuit A makes a 0 to 1 transition, the output of nand gate N15 makes a 1 to 0 transition which, coupled through capacitor C2, produces a negative pulse at the input of inverter 18. Thus, the output of inverter 18 provides a positive pulse to the input of the acquisition circuit AQ7 at the time immediately following a 0 to 1 transition of Ao.

The acquisition circuit AQ7 consists of nand gate N19, having three terminals on the input side and one terminal on the output side. After the selection start switch 4 is operated and released, the output of inverter 5a of the minimum time control circuit MN5 makes a 0 to 1 transition. When and if a selection intersection is selected at the same time or with a slight delay with respect to the 0 to 1 transition of inverter 5a, the output Ao will make a 0 to 1 transition and the output of the pulse forming circuit PS10 will be a positive pulse and at this time the output of the acquisition circuit AQ7 makes a 1 to 0 transition which resets the acquisition request memory circuit ME. In other words, the operation of this circuit AQ7 is that of a monitor circuit whose purpose is to suspend the output 13 of the abovementioned selection circuit 9 (i.e. the output of the electronic clock circuit E1) by resetting the said acquisition request memory circuit ME and thereby suspending further operation of the counter circuit CO2 when all the outputs of the inverter 5a, the resistor R21 and the pulse forming circuit PS10 are 1.

The minimum time control circuit MN5 consists of a monostable multivibrator circuit comprising nand gate N5b, inverter 5a and capacitor C1. The said monostable multivibrator circuit is in a stable condition when the selection start switch 4 is in an ON or 0 condition or ordinary OFF or 1 condition, but a pulse having a fixed pulse width is generated as the output of said minimum time control circuit MN5 during the time capacitor c1 is discharging. This prevents the possible rapid operation of selection start switch 4 from generating a very short pulse at the output of inverter 5a such that it is almost predictable that selection of closely following selection intersections would occur.

In other words, the minimum operation time of selection start switch 4 can be controlled. Thus, it becomes feasible to always acquire the aforementioned selection intersection with essentially equal probability without any effect caused by the operating time of the selection start switch 4. The inhibit circuit IH6 is provided for the purpose of preventing a further selection until the correct switch located at the intersection point in the switch matrix circuit M3 is operated (i.e. open contacts) corresponding to the selection intersection to be removed. The circuit consists of nand gate N6b and inverter 6a.

When the selection start switch 4 is ON or 0 in the process of selecting, the output of nand gate N5b in the minimum time control circuit MN5 is 1. Even if an operator who performs selection does not operate (i.e. open contacts) the switch, corresponding to the already selected selection intersection, by mistake and desires to perform selection, the lamps remain lit and the output of inverter 6a is 0 since the output of resistor R21 (i.e. the feedback control signal 16) is 1, thus inhibiting the output of nand gate N6b (i.e. the output is held at 1). When the operator operates the switch corresponding to the already selected selection intersection, the feedback control signal 16 becomes 0 and the output of inverter 6a becomes 1. Accordingly, the output of nand gate N6b becomes 0 corresponding to the feedback control signal 16 during a time when the selection start switch 4 is ON or 0.

The acquisition request memory circuit ME has the purpose of providing a resettable memory of one bit until the said acquisition request memory circuit ME is set for the purpose of allowing operation of clock selection circuit 9, and comprises a set/reset FLIP-FLOP consisting of nand gates N8a and N8b. It is set such that the output of nand gate N8a becomes a 1 when the output of nand gate N6b is momentarily 0 and is reset so as to obtain a 0 output from nand gate N8a when the output of the acquisition circuit AQ7 is momentarily 0.

FIG. 2 shows the details of the counter circuit CO2. The counter circuit CO2 is driven by the electronic clock circuit E1, and consists of counter circuits X and Y constructed by using binary counter stages and decoders DX and DY, and is operated by the output 13 of the aforesaid electronic clock circuit E1. In FIG. 2, the counter circuit X consists of a three stage sequential type binary counter stages B1, B2 and B3, and the outputs of stages B1 and B3 are connected to the inputs of nand gate N20, the output of which is feedback to reset terminals BR1, BR2 and BR3 of binary counter stages B1, B2 and B3 respectively. Thus a scale-of-5 counter circuit is formed. In other words, five different output combinations are possible so as to correspond to a series of unique selections which are mutually exclusive. The logical value of nand gate N20 is Q1.Q3, and the binary counter stages B1, B2 and B3 are reset at that time only. Here, Q1 and Q3 are the output logical values of the respective binary counter stages B1 and B3.

The nand gates N21 through N25 constitute a decoder DX and usually have an output of 1, but the output being selected at any moment has an output of 0. In FIG. 2, a counter circuit Y consists of four stages of binary counters connected in series B4 through B7, and 16 (i.e. 2.sup.4) output combinations are possible so as to correspond to a series of unique selections which are mutually exclusive, but one combination is not used. Counter circuit Y is connected to the 4 input terminals of each of nand gates N26 through N41, each gate having one output terminal. Nand gate N26 is not used, as mentioned above. The output condition of counter circuit Y is similar to the output condition of counter circuit X previously mentioned.

Since the counter circuits X and Y divide the squarewave of the electronic clock selection circuit E1 by 5 and 16 respectively, and a clock pulse is generated by means of a nand gate, they generate one decoder pulse each in such a way that the output pulses of decoders DX and DY are invariably in phase with each other at any time.

The purpose of switch matrix circuit M3 is to provide memory for selection intersections already removed through selection, and consists of driving transistors TR1 through TR5 and TR6 through TR20, resistors R1 through R5 and R6 through R20, 75 diodes D1 through D75 and 75 switches S1 through S75, being driven by the aforementioned counter circuit CO2 where selection intersections are arranged by using one decoder pulse each from decoder DX and decoder DY corresponding to the above-mentioned 80 numbered intersections. Here, since nand gate N26 is not used as described above, 1 .times. 5 = 5 intersections are not formed as selection intersections, but the feedback control signal 16 is 0 at such times and this causes output Bo to be selected as the output of the electronic clock circuit E1. Thus, 75 selection intersections are produced and are arranged at each point of intersection of the switch matrix circuit M3. Simultaneously, the switch matrix circuit M3 displays which selection intersection is selected by means of a visible display 6 using lamps. A light emitting diode may be substituted for each lamp as well. Also, the switch matrix circuit M3 displays whether previously selected selection intersections have been removed or not by means of the position (i.e. ON or OFF) of each switch in the matrix.

In selection generated by means of coincidence of one decoder pulse from decoder DX at an arbitrary time together with a decoder pulse from decoder DY corresponding to the aforesaid clock pulse, for example, in the case of nand gate N21 and nand gate N40, the current from the power supply B+ flows through lamp LX1, driving transistor TR1, switch S1, diode D1, driving transistor TR19 and lamp LY2 to resistor R21. Thus, a potential difference is produced across resistor R21 and the feedback control signal 16 having a 1 output is feedback to the aforesaid electronic clock circuit E1, because one end of resistor R21 is connected to ground. Diodes D1 through D75 are provided for the purpose of preventing the current from flowing through lamps other than the selected set.

Feedback circuit F4 consists of resistor R21 driven by the above-mentioned switch matrix circuit M3 and is capable of transferring the memory of removed selection intersections to the electronic clock circuit E1 by means of the feedback control signal 16 such that selection may be feasible only when the output of said resistor R21 is 1 and the output of clock circuit A is in a predetermined output condition having just made a 0 to 1 transition. A detailed description of the mode of selection during a same using the Bingo Game unit of the present invention will be made hereafter. Initially, all switches S1 through S75 of the switch matrix circuit M3 are ON (i.e. closed contacts), the selection start switch 4 is "OFF," the feedback control signal 16 is 1 and the output of the acquisition request memory circuit ME is 0. Thus, nand gate N17 is inhibited and the output 15 of the electronic clock circuit E1 has a 1 output having no relationship to outpus Ao and Bo of clock circuits A and B respectively. The current flowing through the selected selection intersection switch is then interrupted by operation of the appropriate switch (i.e. one of S1 through S75) in the switch matrix circuit M3 causing the feedback control signal 16 to become 0 which causes the output of inverter 6a to become 1 which enables nand gate N6b. Next, when selection start switch 4 is operated "ON" in order to begin selection of any one of a series of selection intersections of a single cycle consisting of M selection intersections, the acquisition request memory circuit ME is set which causes its output to change from 0 to 1 and the aforesaid nand gate N17 is enabled. Furthermore, since nand gate N15 is inhibited, selection of squarewave F.sub.A becomes impossible and such a condition allowing selection of squarewave F.sub.B is obtained.

Squarewave F.sub.B advances the counter circuit CO2 to the point where the next selection intersection not previously removed allows current to flow through resistor R21 causing the feedback control signal 16 to become 1 and thus inhibit nand gate N16 and enable nand gate N15 thereby selecting squarewave F.sub.A as the output 13 of nand gate N17 which is 0 at that time until the end of negative pulse P. This process is repeated many times while selection start switch 4 is held "ON". Also, at the end of every negative pulse P when squarewave F.sub.A and the output 13 of nand gate N17 make a 0 to 1 transition, the output of nand gate N15 makes a 1 to 0 transition which is coupled to inverter 18 through C2 causing a positive pulse to appear at the output of inverter 18.

Next, depending on the operator, selection start switch 4 is released or placed "OFF" enabling one input of acquisition circuit AQ7. When by means of either F.sub.A or F.sub.B selection, the counter is advanced to a selection intersection not yet deleted causing feedback control signal 16 to become 1, another input of acquisition circuit AQ7 is enabled. Finally, at the end of negative pulse P, the output of inverter 18 provides a positive pulse fully enabling acquisition circuit AQ7 such that during the pulse time, the output of nand gate N19 becomes 0 resetting the acquisition request memory circuit ME output to 0 and in turn inhibiting the clock output 13 of clock selection circuit E1 thus completing the single selection cycle wherein a single selection intersection is selected. In other words, a series of selection intersections of a single cycle consisting of M cycles of squarewave Ao of clock circuit A is arranged in such a way that one of M unique selection intersections and the transition from 0 to 1 of Ao correspond to each other in every cycle.

Furthermore, since F.sub.A = 1000 c.p.s. and is sufficiently large compared to N=75 and also due to the operation of minimum time control circuit MN5, the probability of selecting any one of 75 selection intersections is substantially 1/75, which is equal to the probability of selecting any other one of the 75 selection intersections and is also essentially independent of the number of selection intersections. Further, since switches in the switch matrix circuit M3 corresponding to previously removed (75-M) selection intersections are OFF (i.e. open contacts in the case where M selection intersections have not yet been removed, the current from the power supply B+ does not flow through the intersection point corresponding to the aforesaid selection intersection which has already been removed and the output across resistor R21 (i.e. the feedback control signal 16) is 0. Accordingly, the 1 input of nand gate N15 is changed to 0 and the 0 input of nand gate N16 is changed to 1, thus output Ao is inhibited and output Bo is selected as output 13 of the above-mentioned electronic clock circuit E1.

Also, since the frequency of clock circuit B is F.sub.B >160,000 c.p.s., 80 cycles of Bo can be contained within the negative pulse portion P of the aforementioned clock circuit A and the 0 to 1 change of the output Ao is still obtained even if any number of totally all 75 selection intersections have been removed, and it is feasible to select selection intersections in any case. In other words, the switch matrix circuit M3 has such a characteristic that any number or the total number of selection intersections can be removed and memorized by means of the switches. Furthermore, the circuit is arranged such that selection is performed independently of the (75-M) selection intersections already removed and the probability of selecting any one selection intersection is 1/M which is equal to the probability of selecting any other one, and further, so that the (75-M) selection intersections already removed are prevented from being selected again by means of the feedback control signal 16. The mode of selection during a game using the Bingo Game Unit of the present invention has been fully described above. However, as shown in FIG. 5 and FIG. 6, as a second embodiment, mechanical sound may be projected to the players to enhance enjoyment of players through a speaker 21 driven by audio unit 20 which has as its inputs the usual microphone 22 where person 23 reads the number of the selected selection intersection and also an input from audio circuit AU contained in the main unit H.

Audio circuit AU consists of nand gate N42, capacitors C4 and C5 and a sound output connector 24. Output Ao of clock circuit A is one input of nand gate N42 and output Q7 of binary counter stage B7 is coupled through capacitor C4 to a second input while the remaining third input is the feedback control signal 16. The output of nand gate N42 is coupled to sound output connector 24 through capacitor C5. Further, in a third embodiment, an initializing circuit IC is incorporated. The circuit consists of nand gate N43, capacitor C6 and resistor R22 and the output of nand gate N43 is connected to reset terminals BR4 through BR7 of binary counter stages B4 through B7 respectively. One input of nand gate N43 is the output of nand gate 8b of acquisition request memory circuit ME while the other is from the power supply B through capacitor C6. This initializing circuit IC changes the mode of selection slightly only at the beginning where upon application of power supply B+ none of the N=75 selection intersections are selected to begin with.

Thus, it is feasible, using the Bingo Game Unit of the present invention, to perform successive selection with equal probability from among 75 uniquely numbered selection intersections or fewer depending upon how many have already been removed. Futhermore, no adjustments are required, operation of the unit is almost automatic and it is easy to see which selection intersections have already been removed.

Claims

I claim:

1. An equal probability selection electronic device for a bingo game allowing a human operator to make, by successive operation, the selection of any one of 75 (or fewer, if some are not selectable) unique selection intersections, comprising:

a switch matrix comprised of 75 slide switches arranged in a 5 .times. 15 Cartesian coordinate form, each slide switch being used to indicate a selection intersection and being individually controllable by the operation of the human operator to define whether or not the slide switch is selectable and lamp indicators operatively positioned to define the intersection selected at the time of selection;

a selector circuit coupled to said switch matrix and comprised of counter circuit means for successively addressing the slide switches;

clock circuit means coupled to said counter circuit means for driving the counter circuit means and providing a clock pulse output having one of a relatively high and relatively low frequency, the relatively high frequency being used only to sweep past any addresses previously selected;

feedback circuit means connected between the switch matrix and the clock circuit means for controlling said clock pulse output such that the clock pulse output is selected to be of low frequency when a selectable slide switch is being addressed and is otherwise selected to be of high frequency; and

selection start switch means arranged to provide, by successive operator use for each desired selection, both a start signal to the clock circuit means for initiating a selection of a slide switch and a stop signal for initiating termination of a selection cycle, the arrangement being such that the clock pulse output may be stopped only when a selectable slide switch is addressed, which occurs at equal time segments of the addressing sequence, regardless of the number of slide switches no longer selectable.

2. A device as recited in claim 1 wherein said clock circuit means has clock frequencies which are asynchronous and further comprising a misselection prevention circuit means operatively coupled and driven by said clock circuit means with a low frequency to inhibit a high frequency for a delay time of 1/(the high frequency output), which eliminates erroneous advancement of the counter circuit means due to the arbitrary phase relationship of the high frequency with respect to the low frequency.

3. A device as recited in claim 1, wherein said clock circuit means comprises a high frequency clock to provide said high frequency output, and a low frequency clock to provide said low frequency output, the low frequency in Hertz being numerically much greater than the number of slide switches, and the high frequency in Hertz being numerically greater than (2N') . (low frequency output), where N' is equal to 5 .times. 16 = 80.

4. A device as recited in claim 3 wherein said clock circuit means has clock frequencies which are asynchronous and further comprising a misselection prevention circuit means operatively coupled and driven by the low frequency clock to inhibit the high frequency clock for a delay time of 1/(the high frequency output), which eliminates erroneous advancement of the counter circuit means due to the arbitrary phase relationship of the high frequency asynchronous clock with respect to the low frequency asynchronous clock.

5. A device as recited in claim 3 further comprising an acquisition request memory operatively coupled to said clock circuit means, a minimum time control circuit means for controlling the minimum operation time of a selection start switch, and inhibit circuit means, said inhibit circuit means including a nand gate for preventing operation of the acquisition request memory until after a currently selected selection intersection has been removed by opening the contacts of the slide switch corresponding to the currently selected selection intersection, one input of said nand gate being connected through an inverter to the feedback circuit means and another input thereof being directly connected to the output of said minimum time control circuit means, the output of said nand gate being connected to said acquisition request memory, said inhibit circuit means being enabled by a change in the signal from said feedback circuit means when the slide switch corresponding to the selected selection intersection is opened, and thereby causing deletion of that selection intersection from future consideration.

6. A device as recited in claim 1 further comprising an acquisition request memory operatively coupled to said clock circuit means, a minimum time control circuit means for controlling the minimum operation time of a selection start switch, and inhibit circuit means, said inhibit circuit means including a nand gate for preventing operation of the acquisition request memory until after a currently selected selection intersection has been removed by opening the contacts of the slide switch corresponding to the currently selected selection intersection, one input of said nand gate being connected through an inverter to the feedback circuit means and another input thereof being directly connected to the output of said minimum time control circuit means, the output of said nand gate being connected to said acquisition request memory, said inhibit circuit means being enabled by a change in the signal from said feedback circuit means when the slide switch corresponding to the selected selection intersection is opened and thereby causing deletion of that selection intersection from future consideration.