Abstract:
A portable dog-training transmitter unit for controlling remote collar-mounted receiver/stimulus units includes first, second, and third switches for causing corresponding transmitted stimulus control signals to be recognized by corresponding first, second, or third receiver/stimulus units. A multiple-position switch sets the use of transmitted codes that control the amplitudes of stimulus signals produced by the recognizing receiver/stimulus unit. The transmitter unit is supported in a holster that is pivotally supported by a belt clip by means of a pivot pin that is pivotally retained in a receiving slot of the belt clip. The transmitter unit includes a controller which polls the states of the various switches to produce a digital signal that is shaped by a buffer circuit, FM modulated, preamplified, and coupled by a simplified matching network to the input of a power amplifier. A single pi matching network is coupled to match an output of the power amplifier to an antenna of the transmitter unit.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The invention relates to small, portable transmitters used for dog training by transmitting stimulation control signals to collar-mounted receivers on one or more dogs being trained, and more particularly to a system that (1) provides remote control of the amplitude of stimulus pulses applied to electrodes which are maintained in contact with the skin of the dog (s), and (2) also provides remote control of the amplitude of open circuit output voltages applied between stimulus electrodes (i.e., when the electrodes are not in electrical contact with the skin of the dog (s)).  
           [0002]    A basic requirement of a remote training device of the general type including stimulus intensity that is controllable by a remote transmitter is that each remotely selected intensity level must reliably and consistently apply the same electrical stimulus level to the animal being trained. If this requirement is not met, inconsistent stimulus levels received by the animal often causes confusion to the animal, which interferes with the training process.  
           [0003]    A shortcoming of some prior remote training systems having remotely selectable control of the amplitude of the stimulus signal between the skin-contacting electrodes is that for the lower values of the intensity settings, neither the open circuit nor the “loaded” electrode voltages applied between the contacting electrodes are high enough to cause effective electrical contact of the electrodes with the animals&#39; skin. The animal does not feel and therefore does not respond to the intended stimulus for lower selected intensity control settings. (A trainer observing the lack of response then is likely to increase the selected stimulus level on the remote transmitter until the animal responds. At that point, the stimulus level actually felt by the animal may suddenly be much higher than is justified by its behavior and may be far too great, causing confusion or fright of the animal which, of course, is counterproductive.) The foregoing problems may be caused by a combination of the dryness of the animals&#39; skin, the tightness of the collar pressing the electrodes against the animals&#39; skin, and various other conditions that cause or contribute to ineffective electrical contact of the electrodes with the animals&#39; skin. The only known reliable way of nevertheless ensuring electrical contact of the electrodes to the animals&#39; skin is to ensure that the open circuit output voltage produced by the secondary winding of the output transformer in the receiver is high enough to arc across any gap or insulative barrier between the electrodes and the animals&#39; skin.  
           [0004]    Commonly assigned U.S. Pat. No. 4,802,482, by Gerald J. Gonda and Gregory J. Farkas, issued Feb. 7, 1989, and incorporated herein by reference, and commonly assigned U.S. Pat. No. 5,054,428, by Gregory J. Farkas, issued Oct. 8, 1991, also incorporated herein by reference, disclose prior remote animal training systems in which intensity of electrical stimulus is remotely controlled by causing the receiver circuits to produce various stimulus waveforms of constant amplitude and selectable duration and/or frequency. The high open circuit stimulus voltage needed is achieved independently of the intensity level selected. The devices disclosed in these patents provide reliable electrical contact of the electrodes to the skin of the animal being trained by providing sufficiently high open circuit voltages to ensure that even low levels of stimulation produced by controlling the output pulse widths and repetition rates are reliably felt by the animal.  
           [0005]    Because of the lack of a wide range of nearly immediately selectable stimulus levels in the prior art remote training devices, professional trainers have had to plan particular training sessions so as to include only activities and circumstances likely to cause dog behaviors which would require stimulus levels within the range determined by the pluggable intensity-level-setting resistors and/or the resistive electrodes on the collar mounted receiver unit. Then, if unexpected behavior or unexpected circumstances occurred during the training session, the trainer often was not able to immediately select a high, effective stimulus level. In such a case, an opportunity for effective training was lost, and the training process may have been set back as a result of inconsistent and/or inappropriate stimulus. That problem is solved by the system disclosed in commonly assigned U.S. Pat. No. 6,170,439, entitled “REMOTE CONTROLLED ANIMAL TRAINING SYSTEM”, by Duncan et al., Ser. No. 09/339,491, issued Jan. 9, 2001, incorporated herein by reference. That patent discloses that even though the circuitry disclosed in the foregoing patents is capable of providing the stimulus voltage with a very wide range of selectable pulse widths and pulse frequencies, the physiology of the dogs being trained is such that the effective range of remotely selectable stimulus that can be achieved by adjusting only the pulse widths and repetition rates of the electrode pulses is much less than is desirable for a wide range of training conditions. The foregoing commonly assigned patent discloses a system which provides remotely controlled stimulus levels that can be promptly changed to any desired level within a very broad range so that a trainer can immediately provide stimulus levels appropriate to any dog behavior likely to occur in any environmental circumstance likely to occur during any training session.  
           [0006]    One of the assignees prior products, Tritronics model A270, allows a trainer to transmit separate stimulus signal/commands from a single handheld transmitter unit to separate remote collar-mounted receiver units on separate dogs. The transmitter unit includes separate pushbutton switches, which, when depressed, cause the transmitter unit to transmit separate stimulus/commands signals to the separate collar-mounted receiver units, respectively.  
           [0007]    Dog trainers frequently have the dog on a leash or check cord, or use a “heeling” stick, any of the which requires the use of one hand. However, the trainer often each to use one hand or even two hands to provide hand signal training of the dog during the training session. During hunting sessions, a dog owner or trainer is likely to carry a gun, two-way radio, binoculars or spotting telescopes and/or the like. It would be very advantageous to a dog trainer and/or a hunter working with a hunting dog to have a remote dog-training transmitter which is easily operable with minimal use of only one hand.  
           [0008]    There is an unmet need for a dog training system which reliably solves the above described problems, and nevertheless is much smaller and less costly than the system disclosed in U.S. Pat. No. 6,170,439.  
         SUMMARY OF THE INVENTION  
         [0009]    Accordingly, it is an object of the invention to provide an improved, small, low-cost, low-power transmitter unit which is adaptable to transmit multiple stimulus control signals to a single collar-mounted receiver unit of a single dog, or alternatively, to transmit separate, independent of stimulus control signals to multiple collar-mounted receivers mounted, respectively, on separate dogs.  
           [0010]    It is another object of the invention to provide an improved, low-power transmitter unit which is adaptable to transmit multiple level stimulus control signals to a single collar-mounted receiver unit of a single dog, or alternatively, to transmit separate, independent continuous stimulus control signals to multiple collar-noted receivers mounted, respectively, on different dogs, and which is smaller and less costly than the system disclosed in U.S. Pat. No. 6,170,439.  
           [0011]    It is another object of the invention to provide small, low-cost, low-power transmitter unit which can be easily deployed to send stimulus control signals to a collar-mounted receiver unit mounted on a dog without the need for the trainer to remove the transmitter from its holster or to remove the holster from a belt clip supporting the holster.  
           [0012]    It is another object of the invention to provide a small, low-cost, low-power transmitter unit which can be easily deployed by a dog trainer to send stimulus control signals to a collar-mounted receiver unit on a dog, with minimal need for the trainer to use either hand to operate the transmitter unit to transmit a stimulus control signals to the collar-mounted receiver unit.  
           [0013]    Briefly described, and in accordance with one embodiment thereof, the invention provides a portable dog-training transmitter unit ( 1 ) for transmitting stimulus control signals to a remote collar-mounted receiver/stimulus unit ( 10 ) on a dog. The transmitter unit a rectangular housing ( 2 ) having opposed the front and rear surfaces, opposed right side and left side surfaces, and opposed top and bottom surfaces and an antenna ( 3 ) extending upward from the top surface. A control panel area ( 2 A) is provided on the upper right portion of the front surface, and first ( 4 ), second ( 5 ), and third ( 6 ) pushbutton switches are disposed in the control panel area ( 2 A) to control first, second, and third functions, respectively, represented by stimulus control signals transmitted by the transmitter unit ( 1 ). A multiple-position thumbwheel detent switch ( 7 ) is disposed in an upper right corner portion of the control panel area ( 2 A) for setting the amplitudes of stimulus signals produced by the collar-mounted receiver/stimulus unit. The first ( 4 ), second ( 5 ), and third ( 6 ) pushbutton switches and the thumbwheel detent switch ( 7 ) have surfaces which are approximately flush with the surface of the control panel area ( 2 A). The thumbwheel detent switch ( 7 ) is disposed in a recess ( 7 A) in an upper right portion of the control panel area ( 2 D). Transmitter circuitry in the housing includes a controller ( 15 ) having a plurality of inputs coupled to the first ( 4 ), second ( 5 ), and third ( 6 ) pushbutton switches and the thumbwheel detent switch ( 7 ) the controller including a first output ( 16 ) conducting digital data representative of the states of the first, second, and third pushbutton switches in the thumbwheel detent switch. A buffer circuit ( 17 ) Includes an input coupled to the first output ( 16 ) of the controller for shaping pulses constituting the digital data. In FM modulator ( 19 ) Has an input coupled to an output ( 18 ) of the buffer, for performing the function of modulating the 27.045 MHZ carrier with the desired digital data. An FM preamplifier ( 22 ) has an input coupled to an output ( 20 ) of the FM modulator, for performing the function of buffering the oscillator and amplifying the signal for use in the output stage. A matching network ( 24 ) has an input coupled to an output ( 23 ) of the FM preamplifier. A power amplifier ( 26 ) has an input coupled to an output ( 25 ) of the matching network. A single pi matching network ( 28 ) has been an input coupled to an output ( 27 ) of the power amplifier and an output ( 63 ) coupled to the antenna ( 3 ). The controller ( 15 ) includes a switch polling program, and executes the switch polling program in response to depressing of any pushbutton switch for setting of a thumbwheel switch to determine the states of the first, second, and third pushbutton switches and the thumbwheel detent switch. The controller ( 15 ) can be configured to cause the first ( 4 ) and second ( 5 ) pushbutton switches, when depressed, to produce different corresponding stimulus intensity levels to be produced by the collar-mounted receiver stimulus unit ( 10 ), wherein the first pushbutton switch ( 4 ), when depressed, causes a continuous a stimulus intensity level of amplitude determined by the setting of the thumbwheel detent switch ( 7 ) to be produced by the collar-mounted receiver/stimulus unit ( 10 ) for as long as the first pushbutton switch ( 4 ) remains depressed, up to a predetermined maximum duration, and the second pushbutton switch ( 4 ), when depressed, causes a predetermined stimulus intensity level of a predetermined duration to be produced by the collar-mounted receiver/stimulus unit ( 10 ). Alternatively, the controller ( 15 ) can be configured to cause the transmitter unit ( 1 ) to transmit different first, second, and third address codes recognizable by first, second, and third remote collar-mounted receiver/stimulus units, respectively, in response to depressing of the first ( 4 ), second ( 5 ), and third ( 6 ) pushbutton switches, respectively. In one embodiment, the housing ( 2 ) is removably supported, a pivot pin ( 67 ) rigidly attached to a rear surface of the holster, and a belt clip  68  in which the pivot pin ( 67 ) is pivotally retained.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]    [0014]FIG. 1 is a perspective view of the portable transmitter unit of the present invention.  
         [0015]    [0015]FIG. 2 is a perspective view illustrating the transmitter of FIG. 1 in a holster pivotally supported by a belt clip.  
         [0016]    [0016]FIG. 3 is a block diagram of the circuitry included in the transmitter unit of FIG. 1.  
         [0017]    [0017]FIG. 4 is a diagram illustrating microcontroller  15  and user input circuitry  13  of FIG. 3.  
         [0018]    [0018]FIG. 5 is a schematic diagram of the buffer circuit  17  of FIG. 3.  
         [0019]    [0019]FIG. 6 is a schematic diagram of the FM modulator  19  of FIG. 3.  
         [0020]    [0020]FIG. 7 is a schematic diagram of the pre-amplifier  22  and matching network  24  of FIG. 3.  
         [0021]    [0021]FIG. 8 is a schematic diagram of the class C power amplifier  26  of FIG. 3.  
         [0022]    [0022]FIG. 9 is a schematic diagram of the matching network  28  of FIG. 3.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0023]    Referring to FIG. 1, transmitter  1  includes a housing  2  and an antenna  3  attached to the top of housing  2 . Housing  1  includes a “control panel” area  2 A on its front face including button switches  4 , 5 , and  6 . A seven-position rotary detent thumbwheel switch  7  is positioned in a recess  7 G a in the upper right corner of control panel area  2 A and housing  2 , so that the knurled edge of the disk-shaped thumbwheel switch  7  can be rotated by the trainer&#39;s thumb as the trainer&#39;s fingers grip the body of housing  2 . Use of the detent switch ensures that each of the six stimulus signal amplitudes controlled by the thumbwheel switch  7  is precisely repeatable. It is important that the trainer be able to know that a certain position of thumbwheel switch  7  always produces the same amplitude of the resulting stimulus signal produced by the remote collar-mounted receiver/stimulus unit. Preferably, the front faces of thumbwheel switch  7  and push button switches  4 , 5 , and  6  are approximately flush with the surface of control panel area  2 A. A light-emitting diode  8  indicates when rf data is being transmitted. Light emitting diode  8  also functions as an indicator or mark on the control panel surface area  2 A with which the intensity setting marks on the face of the thumbwheel switch are aligned, so as to indicate the present intensity setting. Transmitter  1  is easily held in one hand by a trainer, as the length, width, and thicknesses of housing  2  are only 4.80 inches, 1.85 inches, and 1.25 inches, respectively. Also, The trainer usually holds the transmitter housing  2  so that thumbwheel switch  7  and all three switches  4 , 5 ,  6  are all operated with his/her thumb, if the trainer is right-handed. Switches  4 , 5 ,  6  are located along an arc so the same area of the trainer&#39;s thumb naturally contacts the three switches  4 , 5 , and  6 .  
         [0024]    In a first configuration, wherein transmitter  1  transmits signals  3 A to only a single collar-mounted receiver  10  on a single dog, if the trainer to presses the lower push button switches  4 , this causes the collar-mounted receiver to apply a continuous stimulus through the electrodes to the skin of the dog&#39;s neck as long as pushbutton switch  4  is depressed (up to a maximum amount of time). The next switch, pushbutton switch  5 , if depressed by the trainer, causes the remote collar-mounted receiver unit to apply a fixed, predetermined interval of stimulation, rather than a continuous level of stimulation, to the neck of the dog. The interval or duration of the stimulation applied in response to depressing of pushbutton switch  5  is independent of how long pushbutton switch  5  is depressed. In either case, the amplitude of the stimulation pulses applied by the electrodes to the neck of the dog is the amplitude selected by thumbwheel switch  7 .  
         [0025]    Pushbutton switch  6 , if depressed by the trainer, causes the remote collar-mounted receiver unit to the emit an audible tone which is recognizable to the to the dog being trained.  
         [0026]    Transmitter  1  can be reconfigured by a jumper connection so that each of pushbutton switches  4 ,  5 , and  6 , if depressed by the trainer, transmits a stimulus command to a different corresponding collar-mounted receiver unit mounted on the necks of one, two, or three dogs, respectively. The stimulation is applied continuously to the dog corresponding to the depressed pushbutton switch  4 , 5  or  6  for as long as the selected switch is depressed (up to a maximum amount of time). Preferably, the colors of pushbutton switches  4 , 5  and  6  are color-coded relative to the colors of the collars of corresponding receiver units mounted on the necks of the multiple dogs.  
         [0027]    Referring to FIG. 2, a housing  2  of transmitter  1  is shown in a holster  65 . Holster  65  includes a cutout  65 A that allows the trainer to access to pushbutton switches  4 , 5 , and  6  and to thumbwheel switch  7 . A top flap  65 B of holster  65  has a Velcro connection on its bottom service. A matching Velcro connection is provided on the top surface of a second flap  65 C, to retain the body  2  of transmitter  1  within holster  65 . Holster  65  is pivotally, removably mounted on a conventional belt clip  68  by means of a pivot pin  67  extending horizontally outward from a mounting plate  66  attached to the vertical rear surface of holster  65 .  
         [0028]    A trainer therefore can conveniently the press one or more of pushbutton switches  4 , 5 , and  6  and intensity selection control thumbwheel switch  7  without necessarily removing transmitter  1  and holster  65  from belt clip  68 .  
         [0029]    The trainer also can pivot transmitter  1  and holster  65  about pivot pin  67  to orient antenna  3  in a preferred direction, if desired. The pivot pin  67  includes a shaft  67 A and retaining head  67 B which retains holster  65  securely in a slot  68 A belt clip  68 .  
         [0030]    [0030]FIG. 3 shows a block diagram of the circuitry enclosed within housing  2 . Referring to FIG. 3, the transmitter circuitry  11  in housing  2  of transmitter  1  includes a microcontroller  15 , which can be a commercially available PIC16C621C microcontroller which includes a microprocessor, memory, and input/output interface circuitry. If the dog trainer selects one of the available six intensity level settings by means of thumbwheel switch  7 , and then depresses one or more of pushbutton switches  4 ,  5  and  6 , then controller  15  produces a serial digital data output stream representing a function code on conductor  16 . If transmitter  1  is configured (by a suitable jumper connection) to communicate with multiple collar-mounted receivers on different dogs, the digital output stream also includes an address that must be recognized by the intended collar-mounted receiver before it can respond to the received function code. The function code, when received by the collar-mounted receiver unit actuates the selected stimulation level to be produced by the selected collar-mounted receiver. However, if transmitter  1  is configured for communication only with a single collar-mounted receiver, then the function code also determines whether continuous stimulation corresponding to depressing of pushbutton  4  or a predetermined duration of stimulation corresponding to depressing of pushbutton  5  is to be applied by the single collar-mounted receiver to the neck of the single dog. Furthermore, if transmitter  1  is configured for communication only with a single dog, the function code also determines whether the audible tone function of the receiver should be actuated, in accordance with whether or not pushbutton switch  6  has been depressed.  
         [0031]    Still referring to FIG. 3, digital data on conductor  16  is provided as an input to a buffer circuit  17 . Buffer circuit  17  produces an output signal on conductor  18  which is applied to the input of an FM modulator circuit  19 , which has a center frequency of 27.045 MHZ, with a +or −8 kilohertz deviation. The output of FM modulator  19  is applied by conductor  20  to the input of an FM preamplifier  22 . The output of preamplifier  22  is applied by conductor  23  to the input of a matching network  24 . The output of matching network  24  supplied by a conductor  25  to the input of a class C power amplifier  26 , the output of which is applied by conductor  27  to the input of a single Pi matching network  28 . The output of single Pi matching network  28  is applied by conductor  63  to antenna  3 .  
         [0032]    [0032]FIG. 4 illustrates the connections of controller  15  to the user input circuitry  13  including pushbutton switches  4 , 506  and thumbwheel switch  7 . FIG. 4 also illustrates the connections of a regulated supply voltage V DD  to the positive supply voltage terminal of controller  15  to light emitting diode  8 , which appears on the control panel of transmitter  1  in FIG. 1. One terminal of each of pushbutton switches  4 , 5   6  is coupled by resistor to a corresponding input of controller  15 . Similarly, each of the six terminals of thumbwheel switch  7  is connected by a corresponding resistor to a corresponding input, respectively, of controller  15 . Controller  15  “awakens” from a “sleep unquote condition and produces a signal PWRON on conductor  29  in response to sensing the depressing of any one of the pushbutton switches  4 ,  5  or  6 . The signal PWRON then provides power to all of the rf stages and thereby enables transmitter unit  1  to operate.  
         [0033]    Controller  15  operates to detect the state of each of the switch inputs by executing a polling routine and then producing a serial digital data output stream that includes function codes and address information to be transmitted to one or more collar-mounted receivers to enable them to generate the level of stimulation represented by the function code. Note that this technique replaces a prior technique in which a controller detects the switch inputs using a reset interrupt signal to reset the controller, causing it to read the states of the actuated switches. The improved polling routine technique avoids problems associated with driving the reset interrupt function of the controller from two different stimuli, specifically, the excessive amount of time required to execute interrupt subroutines. Use of the polling routine was found to allow use of simpler programming of microcontroller  15 , use of simpler circuit design, and substantially faster response of the circuitry to depressing of one of the pushbutton switches  4 ,  5 , or  6 .  
         [0034]    Referring to FIG. 5, buffer  17  includes an NPN transistor  30  having its base coupled by resistor  31  and to the output  16  of controller  15 . The inner of transistor  30  is connected to ground, and its collector is connected by conductor  18  to one terminal of a resistor and  32 . The other terminal resistor  32  is connected to conductor  33 , on which a switched battery voltage is applied. Note that the simple buffer circuit shown in FIG. 5 replaces a much more complex prior multistage pulse shaper circuit including two operational amplifiers,  4  capacitors, and nine resistors.  
         [0035]    Referring to FIG. 6, FM modulator  19  includes an input connected by conductor  18  to the output of buffer  17 . Conductor  18  is connected to the cathode of a varactor diode  35 , which functions as a variable capacitor, having an anode connected to ground. Varying the voltage across varactor diode  35  allows FM modulation of the carrier signal. Conductor  18  also is connected one terminal of a crystal  37 , the other terminal of which is connected by conductor  34  to the base of an NPN transistor  40  and also to the junction between a resistor  39  and a resistor  38 . A resistor  38  is coupled to ground, and resistor  39  is coupled by conductor  29  to the PWRON signal produced by controller  15 . The emitter of the transistor  40  is coupled by conductor  71  to one terminal of resistor  41  and to the junction between capacitors  42  and  43 . The other terminal of resistor  41  is connected to ground. Conductor  71  is coupled by capacitor  43  to ground and is coupled by capacitor  42  to conductor  70 . Conductor  70  is connected to one terminal of resistor  45 , one terminal inductor  44 , and the collector of transistor  40 . The other terminal of inductor  44  is connected to the regulated supply voltage V DD . The other terminal of resistor  45  is connected to conductor  20 .  
         [0036]    [0036]FIG. 7 shows the circuitry for FM preamplifier  22  and matching network  24  of FIG. 3.  
         [0037]    FM preamplifier  22  includes a capacitor  46  having one terminal connected by conductor  20  to the output of FM modulator  19  and another terminal connected by conductor  49  to the junction between the resistors  47  and  48  and to the base of an NPN transistor  50 . A second terminal of resistor  48  is connected to ground. A second terminal of resistor  47  is connected to conductor  33 , on which the switched battery voltage is produced. The emitter of transistor  50  is connected to ground, and its collector is connected by conductor  23  to one terminal of inductor  51  and to one terminal of capacitor  52 . The second terminal of inductor  51  is connected to switched battery voltage conductor  33 . The second terminal of capacitor  52  is connected by conductor  25  to one terminal of inductor  53 , the other terminal of which is connected to ground. Note that the use of capacitor  52  (which may have a value of 0.01 microfarads) as shown in matching network  24  replaced the use of a 4:1 stepdown transformer in a prior analogous circuit. Capacitor  52  requires far less space and is far less costly than the prior 4:1 stepdown transformer. Nevertheless, the use of capacitor  52  was found to accomplish the same benefit as the 4:1 stepdown transformer in transmitter  1 .  
         [0038]    Referring to FIG. 8, conductor  25  also is connected to the input of a class C power amplifier  26 . Conductor  25  is connected to the base of an NPN transistor  56  having its emitter connected to ground and its collector connected by conductor  27  to one terminal of inductor  57 . The other terminal of inductor  57  is connected to the battery voltage V BATT  produced by a conventional nine volt battery.  
         [0039]    Referring to FIG. 9, single pi matching network  28  includes an input connected by conductor  27  to the output of class C power amplifier  26 . The matching network  28  includes a capacitor  58  connected between conductor  27  and ground. An inductor  59  is connected between conductors  27  and  61 . A capacitor  60  is connected between conductor  61  and ground. A capacitor  62  is connected between conductors  61  and  63 . A resistor  64  is connected between conductor  63  and ground. Conductor  63  conducts the output of matching network  28  to antenna  3 . Note that single pi matching network  28  provides a high-pass filtering characteristic which matches the high impedance of antenna  3 . This is in contrast to a prior matching network which required use of a much larger, much more costly double pi network including three inductors, rather than one inductor, to match the high impedance of antenna  3  to the output of power amplifier  26 . A 40 percent reduction in space required by matching network  28  is accomplished by the single pi circuit shown in FIG. 9.  
         [0040]    Transmitter  1  can be configured as either a multi-dog, single-stimulus-function transmitter or as a single-dog, multi-stimulus-function transmitter simply by either providing or not providing a jumper  54  connected to an input of microcontroller  15 . Such a jumper is shown as switch  54  in FIG. 4. Microcontroller  15  is programmed to read the state of the input to which the jumper  54  is connected or not connected and determines whether to operate in a single-dog, multi-stimulus-mode or a multi-dog, single-stimulus-mode.  
         [0041]    While the invention has been described with reference to several particular embodiments thereof, those skilled in the art will be able to make the various modifications to the described embodiments of the invention without departing from the true spirit and scope of the invention. It is intended that all elements or steps which are insubstantially different or perform substantially the same function in substantially the same way to achieve the same result as what is claimed are within the scope of the invention.