Abstract:
An intercom system enabling a plurality of users to listen to and at least one user to speak to and listen to a remote user. A base station communicates with the remote user. A plurality of ear pieces is wearable by the plurality of users, each of the plurality of ear pieces being capable of wirelessly communicating with the base station. Each of the plurality of ear pieces is capable of listening to the base station within a first range of the base station. At least one of the plurality of ear pieces being capable of wirelessly speaking to the base station within a second range of the base station. The second range is larger than the first range. Thus, one of the plurality of users wearing at least one of the plurality of ear pieces may listen and talk with the remote user only within the first range of the base station and the remainder of the plurality of users wearing the remaining ear pieces may only listen to the remote user outside of the first range of the base station but inside of the second range of the base station.

Description:
TECHNICAL FIELD  
         [0001]    This invention relates to intercom systems and, more particularly, to intercom systems of the type enabling a plurality of users to listen to and at least one user to speak to and listen to a remote user.  
         BACKGROUND  
         [0002]    It is common for retail establishments, particularly restaurants, to facilitate drive-up customers with drive-up lanes and windows to service the customer. A customer will typically drive up to a menu/order board and communicate the customer&#39;s wishes from the vehicle to staff, including an order taker, inside the retail establishment. The customer, still in the vehicle, will then proceed to one or more windows in order to pay for the purchase, if required, and pick up the merchandise.  
           [0003]    An intercom system typically facilitates communication between the occupant of the vehicle and the staff inside the establishment. In a “fast food” restaurant situation, a post mounted speaker and microphone, located near a menu board, is hard wired to an intercom base station located inside the restaurant. The base station wirelessly communicates with a portable device worn by an order taker. The portable device is typically a transceiver worn as a belt pack and an accompanied wired headset. Alternatively, in some instances, the portable device is self-contained on a wearable headset eliminating the need for a belt pack but resulting in a relatively bulky and unsightly headset. The order taker typically listens continually to the post mounted microphone and presses a button in order to speak to the vehicle occupant as needed.  
           [0004]    Often it is desirable to have other restaurant employees listen to the conversation between the order taker and the vehicle occupant. For example, a cook can listen as the order is actually given to the order taker and can start preparation for the order even before the order is officially entered into the restaurant&#39;s order system by the order taker. In a typical fast food restaurant, employees beyond the order taker, such as a cook, can listen to the vehicle occupant but such additional employees must wear the same belt pack that the order taker typically wears. The combination belt pack and head set, or the self-contained headset, are not only expensive but are also bulky and obtrusive. This effectively limits how many restaurant employees can wear the device and what activities they can do while wearing the device. Further, the belt pack and headset combination typically suffers from reliability problems due to frequent damage to the connecting wire between the belt pack and headset.  
           [0005]    Also it may be desirable for a fast food restaurant to have more than one employee available who can take orders. A belt pack and headset combination could be switched from one employee to another. However, such switching is cumbersome and results in some downtime during switch over limiting the effectiveness of this option. Multiple employees could each wear a separate belt pack and headset combination and each could be ready to take orders. Only the actual order taker would actually press a button activating the speak portion of the transceiver on their belt pack. Again, this option is expensive and the obtrusiveness of the belt pack and headset combination limits the activities of the employee who is not taking orders.  
         SUMMARY OF THE INVENTION  
         [0006]    The intercom system of the present invention provides advantages which are not immediately apparent. The portable device associated with the present invention is smaller in size, is less costly and is less obtrusive, expanding the number of people who can and will wear the portable device. Further, the retail establishment has increased efficiencies due to an expanded number of people who are able to listen to the conservation between the vehicle occupant and the order taker.  
           [0007]    The intercom system of the present invention has a different range over which an employee wearing the portable device can be from the base station, or a cradle holding a belt pack, for listening and for talking. While employees wearing the portable device may listen to the conversation over a relatively broad range, employees wearing the portable device may only talk on the intercom system when such employees are positioned a relatively small distance from the base station or cradle.  
           [0008]    The dichotomy of range between “talk and listen” and “listen only” allows multiple employees to have the capability to talk. For example, any one of the employees could be an order taker at any given point in time, but only one employee could have the ability to talk, namely the person physically located close to base station or cradle. Anyone else who is not close enough to the base station or cradle would not have the ability to talk. This effectively prevents anyone but the order taker from talking to the vehicle occupant regardless of the switch position of an employee&#39;s transceiver and regardless of whether or not the transmit button has been pushed, even accidentally. Prevention of inadvertent speech is a significant safeguard. Employees not intending to be speakers and who are not expecting their speech to be heard by the vehicle occupant can be assured that it won&#39;t be heard. Thus, a cook who listens to an order may verbally communicate with his/her assistants without fear that the comments will be heard by the vehicle occupant regardless of the switch settings on his/her portable device. Yet each employee who wears the portable device still has the capability of talking to the vehicle occupant by simply to going near the location of a base station or cradle.  
           [0009]    If more than one person is at the order taker&#39;s location, i.e., next to the base station or cradle, then only the person or persons whose portable device has been placed in transmit mode will transmit to and talk to the vehicle occupant. Thus, all existing precautions and safeguards are still present. In addition, the additional safeguard of proximity is also present.  
           [0010]    The present invention also provides “hands free” talking ability, if desired. The order taker does not need to push a button to talk to the vehicle occupant. Rather, the order taker can leave his/her portable unit in transmit mode as he or she moves around the restaurant. The order taker won&#39;t actually be able to speak to the vehicle occupant, however, until the order taker moves to the proximity of the base station or cradle. The order taker can simply walk up and speak. The act of moving to within the proximity of the base station or cradle effectively enables speech to the vehicle occupant. Similarly, the order taker knows that walking away from the base station or cradle effectively disables his/her ability to speak to the vehicle occupant.  
           [0011]    In one embodiment, the present invention provides an intercom system enabling a plurality of users to listen to and at least one user to speak to and listen to a remote user. A base station communicates with the remote user. A plurality of ear pieces is wearable by the plurality of users, each of the plurality of ear pieces being capable of wirelessly communicating with the base station. Each of the plurality of ear pieces is capable of listening to the base station within a first range of the base station. At least one of the plurality of ear pieces is capable of wirelessly speaking to the base station within a second range of the base station. The second range is larger than the first range. Thus, one of the plurality of users wearing at least one of the plurality of ear pieces may listen and talk with the remote user only within the first range of the base station and the remainder of the plurality of users wearing the remaining ear pieces may only listen to the remote user outside of the first range of the base station but inside of the second range of the base station.  
           [0012]    In another embodiment, the present invention provides an intercom system enabling a first user to communicate with a second user. A base station communicates with the remote user. An ear piece is wearable by the first user, the ear piece being capable of wirelessly communicating with the base station. The ear piece is capable of listening to the base station within a first range of the base station. The ear piece being capable of wirelessly speaking to the base station within a second range of the base station. The second range is larger than the first range. Thus, the first user wearing the ear piece may listen and talk with the remote user only within the first range of the base station and may only listen to the remote user outside of the first range of the base station but inside of the second range of the base station.  
           [0013]    In another embodiment, the present invention provides an intercom system enabling a plurality of users to listen to and at least one user to speak to and listen to a remote user. A base station communicates with the remote user. A portable communication device wirelessly communicates with the base station on a first frequency. A cradle is adapted to host the portable communication device and is operatively coupled to the portable communication device when hosting the portable communication device. A plurality of ear pieces are wearable by the plurality of users, each of the plurality of ear pieces being capable of wirelessly communicating with the portable communication device through the cradle on a second frequency. The plurality of ear pieces are capable of listening to the portable communication device through the cradle within a first range of the portable communication device. At least one of the plurality of ear pieces is capable of wirelessly speaking to the portable communication device through the cradle within a second range of the portable communication device. The second range is larger than the first range. Thus, one of the plurality of users wearing the at least one of the plurality of ear pieces may listen and talk with the remote user only within the first range of the base station and a remainder of the plurality of users wearing a remainder of the plurality of ear pieces may only listen to the remote user outside of the first range of the base station but inside of the second range of the base station.  
           [0014]    In another embodiment, the present invention provides an intercom system enabling a first user to communicate with a remote user. A base station communicates with the remote user. A portable communication device wirelessly communicates with the base station on a first frequency. A cradle is adapted to host the portable communication device and is operatively coupled to the portable communication device when hosting the portable communication device. An ear piece is wearable by the first user, the ear piece being capable of wirelessly communicating with the portable communication device through the cradle on a second frequency. The ear piece is capable of listening to the portable communication device through the cradle within a first range of the portable communication device. The ear piece is capable of wirelessly speaking to the portable communication device through the cradle within a second range of the portable communication device. The second range is larger than the first range. Thus, the first user wearing the ear piece may listen and talk with the remote user only within the first range of the base station and may only listen to the remote user outside of the first range of the base station but inside of the second range of the base station.  
           [0015]    In another embodiment, the present invention is useful in an intercom system enabling a first user to communicate with a remote user, having a base station for communicating with the remote user and a belt pack for wirelessly communicating with the base station on a first frequency. A cradle is adapted to host the belt pack and is operatively coupled to the belt pack when hosting the belt pack. An ear piece is wearable by the first user, the ear piece being capable of wirelessly communicating with the belt pack through the cradle on a second frequency. The ear piece is capable of listening to the belt pack through the cradle within a first range of the belt pack. The ear piece is capable of wirelessly speaking to the belt pack through the cradle within a second range of the belt pack. The second range is larger than the first range. Thus, the first user wearing the ear piece may listen and talk with the remote user only within the first range of the base station and may only listen to the remote user outside of the first range of the base station but inside of the second range of the base station.  
           [0016]    In another embodiment, the present invention is useful in an intercom system enabling a first user to communicate with a remote user, having a base station for communicating with the remote user and a plurality of belt packs for wirelessly communicating with the base station on a first frequency. A cradle is adapted to host one of the plurality of belt packs and is operatively coupled to the one of the plurality of belt packs when hosting the one of the plurality of belt packs. An ear piece, wearable by the first user, is capable of wirelessly communicating with the one of the plurality of belt packs through the cradle on a second frequency. The ear piece is capable of listening to the one of the plurality of belt packs through the cradle within a first range of the one of the plurality of belt packs. The ear piece is capable of wirelessly speaking to the one of the plurality of belt packs through the cradle within a second range of the one of the plurality of belt packs. The second range is larger than the first range. Thus, the first user wearing the ear piece may listen and talk with the remote user only within the first range of the base station and may only listen to the remote user outside of the first range of the base station but inside of the second range of the base station.  
           [0017]    In a preferred embodiment, the second range is an order of magnitude greater than the first range.  
           [0018]    In a preferred embodiment, the second range is twenty-five times greater than the first range.  
           [0019]    In a preferred embodiment, the first range is not more than two meters.  
           [0020]    In a preferred embodiment, the second range is on the order of fifty meters.  
           [0021]    In a preferred embodiment, at least one of the ear pieces is switchable between listen only and listen and talk modes.  
           [0022]    In a preferred embodiment, the invention further comprises a remotely located speaker and microphone operatively coupled to the base station for communicating with the remote user.  
           [0023]    In a preferred embodiment, the portable communication device is a belt pack wearable by one of the plurality of users.  
           [0024]    In another embodiment, the present invention provides a method of communicating using an intercom system enabling a plurality of users to listen to and at least one user to speak to and listen to a remote user, a base station for communicating with the remote user; and a plurality of ear pieces wearable by the plurality of users, each of the plurality of ear pieces being capable of wirelessly communicating with the base station, each of the plurality of ear pieces being capable of listening to the base station within a first range of the base station, at least one of the plurality of ear pieces being capable of wirelessly speaking to the base station within a second range of the base station, and the second range being larger than the first range. The plurality of users who are within the second range of the base station but who are not within the first range of the base station are allowed to listen to the remote user through the base station. Moving at least one user to within the first range of the base station enables both listening to and talking to the remote user.  
           [0025]    In another embodiment, the present invention provides a method of communicating using an intercom enabling a first user to communicate with a remote user, a base station for communicating with the remote user, a belt pack for wirelessly communicating with the base station on a first frequency; a cradle adapted to host the belt pack and being operatively coupled to the belt pack when hosting the belt pack; and an ear piece wearable by the first user, the ear piece being capable of wirelessly communicating with the belt pack through the cradle on a second frequency, the ear piece being capable of listening to the belt pack through the cradle within a first range of the belt pack, the ear piece being capable of wirelessly speaking to the belt pack through the cradle within a second range of the belt pack, the second range being larger than the first range. The belt pack is hosted in the cradle. The plurality of users who are within the second range of the base station but who are not within the first range of the base station are allowed to listen to the remote user through the base station. Moving at least one user moving to within the first range of the base station enables both listening to and talking to the remote user.  
           [0026]    In a preferred embodiment, the second range is an order of magnitude greater than the first range.  
           [0027]    In a preferred embodiment, the first range is not more than two meters.  
           [0028]    In another embodiment, the present invention provides, an intercom system having a base station, an ear piece wearable by a user, the ear piece being capable of wirelessly communicating with the base station, wherein the ear piece is switchable between listen only and listen and talk modes.  
           [0029]    In another embodiment, the present invention provides a device for allowing a user to communicate with a base station. An ear piece is adaptable to be attachable to an ear of the user, the ear piece being capable of wireless communication with the base station. A tether is attached to the ear piece and is adapted to be attached to an article of clothing being worn by the user. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0030]    [0030]FIG. 1 illustrates a prior art intercom system utilizable in a drive up retail establishment;  
         [0031]    [0031]FIG. 2 illustrates a prior art belt pack for use in the prior art intercom system of FIG. 1;  
         [0032]    [0032]FIG. 3 illustrates an embodiment of an intercom system of the present invention;  
         [0033]    [0033]FIG. 4 illustrates a cradle for holding a belt pack in an embodiment of intercom system of the present invention;  
         [0034]    [0034]FIG. 5 illustrates a belt pack being held in a cradle of FIG. 4 for use in an embodiment of an intercom system of the present invention;  
         [0035]    [0035]FIG. 6 illustrates an ear set for use in an embodiment of an intercom system of the present invention;  
         [0036]    [0036]FIG. 7 is a diagrammatic illustration of the system signal path of listen mode in an embodiment of an intercom system of the present invention;  
         [0037]    [0037]FIG. 8 is a diagrammatic illustration of the signal path in a base station in listen mode in an embodiment of an intercom system of the present invention;  
         [0038]    [0038]FIG. 9 is a diagrammatic illustration of the signal path in a belt pack in listen mode in an embodiment of an intercom system of the present invention;  
         [0039]    [0039]FIG. 10 is a diagrammatic illustration of the signal path in a secondary transceiver in listen mode in an embodiment of an intercom system of the present invention;  
         [0040]    [0040]FIG. 11 is a diagrammatic illustration of the system signal path of talk mode in an embodiment of an intercom system of the present invention;  
         [0041]    [0041]FIG. 12 is a diagrammatic illustration of the signal path in a secondary transceiver in talk mode in an embodiment of an intercom system of the present invention;  
         [0042]    [0042]FIG. 13 is a diagrammatic illustration of the signal path in a belt pack in talk mode in an embodiment of an intercom system of the present invention;  
         [0043]    [0043]FIG. 14 is a diagrammatic illustration of the signal path in a base station in talk mode in an embodiment of an intercom system of the present invention; and  
         [0044]    [0044]FIG. 15 illustrates an alternative embodiment of an intercom system of the present invention.  
     
    
     DETAILED DESCRIPTION  
       [0045]    [0045]FIG. 1 illustrates a prior art intercom system useful in a retail establishment  10  having a drive up facility, such as a restaurant, and particularly useful in a fast food restaurant having a drive up facility. Speaker  12  and microphone  14  are post mounted near a menu board (not shown) adjacent the drive up lane at establishment  10 . Speaker  12  and microphone  14  are connected via cable  16  to base station  18  in the interior of establishment  10 . An order taker  20  is able to communicate wirelessly to base station  18  and via cable  16  to speaker  12  and microphone  14  and, ultimately, a customer present in a vehicle in the drive up lane near the post mounted speaker  12  and microphone  14 . Typically, order taker  20  wears a belt pack  22  coupled to an associated headset  24  by wire  26 . Head set  24  contains an ear piece or ear pieces for listening and a microphone for talking. Belt pack  22  contains electronics enabling wireless communication to base station  18 . Belt pack  22  commonly includes at least one button which order taker  20  may press to enable belt pack  22  to transmit to base station  18  and, via wire  16 , to the customer located near the drive up post. Otherwise, belt pack  22  is commonly in “listen only” mode enabling order taker  20  to listen to the customer but not to talk to the customer.  
         [0046]    A prior art belt pack  22  is illustrated in FIG. 2. Belt pack  22  contains communication components enabling belt pack  22  to wirelessly communicate with base station  18 . It is physically formed for ease in wearing at the waist of order taker  20  and in attachment to clothing of order taker  20 , for example, by attachment to the belt of order taker  20 .  
         [0047]    Buttons on the top of belt pack  22  enable order taker  20  to control the functioning of belt pack  22 . Button  26  (T 1 ) and button  28  (T 2 ) enable belt pack  22  to wirelessly communicate with base station  18  on either of two different frequencies. This enables a single belt pack  22  to communicate on either of two separate intercom systems. Only one of the two frequencies is utilized in a single intercom system. Button  30  (Lock) enables order taker  20  to put belt pack  22  in a continuous transmit mode. When button  30  is engaged, belt pack  22  transmits continuously to base station  18  enabling order taker  20  to talk to the drive up customer without using a hand to otherwise push a button. However, this continuous talk mode also enables the drive up customer to hear everything that order taker  20  says whether or not order taker  20  intends the drive up customer to hear.  
         [0048]    Button  32  (On) and button  34  (Off) are self explanatory. Volume buttons  36  enable order taker  20  to increase or decrease the volume of sound occurring at ear pieces of head set  24  and the volume of order taker  20 &#39;s voice through the microphone contained in head set  24 .  
         [0049]    In use, order taker  20  hooks belt pack  22  to his/her belt, places head set  24  on his/her head and connects wire  26  between belt pack  22  and head set  24 . Order taker  20  turns belt pack ON (button  32 ) and listens to any drive up customer appearing near microphone  14 . Order taker  20  may also walk over to base station  18  and press a button on base station  18  to enable order taker  20  to talk to the drive up customer. And, alternatively, order taker  20  may use lock button  30  to enable “hands free” talking to the drive up customer. Page button  38 , when pressed, enables order taker  20  to speak with other similarly equipped employees without allowing the drive up customer to hear the conversation.  
         [0050]    [0050]FIG. 3 illustrates an embodiment of an intercom system of the present invention. As in the prior art system illustrated in FIG. 1, post mounted speaker  12  and microphone  14  are connected via a cable  16  to a base station  18  located inside retail establishment  10 , such as a restaurant. However, in the intercom system illustrated in FIG. 3, belt pack  22 , instead of being worn by order taker  20 , is now held in a relatively fixed location by cradle  40 . Belt pack  22  still wirelessly communicates directly with base station  18  on a frequency F1. While cradle  40  and belt pack  22  are illustrated in FIG. 3 as being located in close proximity to base station  18 , it is contemplated that cradle  40  and belt pack  22  may be located anywhere within or around retail establishment  10  so long as belt pack  22  remains in wireless range of base station  18 . Alternatively, belt pack  22  may be hardwired to base station  18  instead of relying on the existing wireless communication between belt pack  22  and base station  18 .  
         [0051]    Belt pack  22  is operatively coupled to electronics contained in cradle enabling wireless communication with one or more ear sets  44  which can be worn by employees or other occupants of retail establishment  10 . Wireless communication between cradle  40  and ear sets  44  occur at a frequency F2, different from wireless frequency F1 established for communication between belt pack  22  and base station  18 . Note that wireless communication frequency F2 is not analogous to the second frequency selectable by pushing T 2  button  28  on prior art belt pack  22 . As noted above, pushing T 2  button  28  on belt pack  22  allows belt pack  22  to wirelessly communicate with base station  18  on a second frequency. It does not allow belt pack  22  to wirelessly communicate with an ear set  44 .  
         [0052]    Order taker  20  and another employee  42  of retail establishment  10  each wear an ear set  44  worn on the head in a manner similar to conventional hear aids. Each ear set  44  communicates wirelessly on frequency F2 with cradle  40 . Since cradle  40  is directly coupled, preferably via wire, to belt pack  22 , since belt pack  22  can communicate with base station  18 , and since base station  18  can communicate with speaker  12  and microphone  14 , ear set  44  can communicate with the occupant of a vehicle located in the drive up lane in the proximity of speaker  12  and microphone  14 .  
         [0053]    The new intercom system operates with a plurality of ear sets  44  from a single base station  18 . Ear sets  44  communicate wirelessly on frequency F2 to the fixed location of cradle  40 . A relatively high power transmitter in cradle  40  allows ear sets  44  located throughout a relatively wide area of retail establishment  10  to listen to the conversation with the drive up customer. Typically, the listen range for ear sets  44  can be in the approximately fifty (50) meters range or can be in the six (6) to nine (9) meters range. Preferably, a 0.5 milliwatts transmitter is utilized in cradle  40 . However, a relatively low power transmitter, preferably 0.05 milliwatts, in ear sets  44  allows ear sets  44  to talk with the drive up customer only when the wearer of ear set  44  is within talking range of cradle  40 , less than the listen range and, preferably approximately two meters.  
         [0054]    This intercom system enables all wearers of ear sets  44  to listen to the conversation between order taker  20  and a person, for example, ordering from a vehicle located near the remote post holding speaker  12  and microphone  14 . However, only the person, typically order taker  20 , wearing ear set  44  is enabled to talk to the person ordering. This forced range dichotomy between listening and talking ensures that only one person can talk to the person ordering (assuming only the order taker is physically located in retail establishment  10  at an ordering location). This also enables order taker  20  to talk with the person in the vehicle ordering without hands (hands free) or not by simply moving closer to or farther away, respectively, from the fixed cradle  40  location, typically the ordering station. Order taker  20  can not talk to the person in the vehicle ordering without being in near proximity to the ordering station, for example, but may easily “switch” to talk mode, without using hands, by moving in close proximity to the ordering station (cradle  40 ). Further, this forced dichotomy in range eliminates potential confusion from more than one person talking with the person in the ordering vehicle and eliminates the danger of the person in the ordering vehicle from hearing an inappropriate comment from a restaurant employee who does not realize that their microphone is live.  
         [0055]    However, in a preferred embodiment, to reduce power consumption and prevent any possibility of a person wearing ear set  44  from being accidentally overheard by the person in the ordering vehicle, ear set  44  contains a three position switch, namely OFF, RECEIVE ONLY and TRANSMIT/RECEIVE. Only in the TRANSMIT/RECEIVE mode would ear set  44  be able to talk to cradle  40  and, hence, to the person in the ordering vehicle. In RECEIVE ONLY mode, power to transmitter portion of transceiver in ear set  44  is disabled.  
         [0056]    The operating range of “talk mode” of F2 wireless communication frequency may be extended by electrically coupling the F2 signal to the retail establishment&#39;s electrical wiring which then serves as a large antenna. Further, several belt pack  22  and cradle  40  combinations may be located in a building to increase coverage. In this case, one or more of belt packs  22  would communicate with base station  18 .  
         [0057]    [0057]FIG. 4 is an illustration of cradle  40  having a back plane  46  and a lower lip  48 . Back plane  46  allows cradle  40  to be easily mounted to a wall. Lower lip  48  allows belt pack  22  to be placed into and secured by cradle  40 . As noted above, cradle  40  contains electronics allowing cradle  40  to wirelessly communicate with ear set  44 . Preferably, the physical connection between belt pack  22  and cradle  40  is a modular telephone connector. FIG. 5 is an illustration of cradle  40  holding belt pack  22 .  
         [0058]    [0058]FIG. 6 is a close-up view of ear set  44  having a main body  50  acoustically coupled to an ear piece  52 . Tether  54  is secured to ear set  44  through hole  56 . Clip  58 , at one end of tether  56 , helps to secure ear set  44  to the wearer. This is important to help prevent ear set  44  from inadvertently falling into a piece of equipment, such as a French fry fryer, or falling onto the floor and being destroyed.  
         [0059]    [0059]FIG. 7 is a diagrammatic illustration of the signal path of an embodiment of the intercom system of the present invention in “listen” mode, i.e., when ear set  44  wearers are listening to the person in the ordering vehicle. In listen mode, microphone  14  picks up the voice of the person ordering. This audio signal is sent via cable  16  (FIG. 3) to base station  18 . A radio frequency signal is then transmitted via wireless frequency F1 to belt pack  22  being held in cradle  40 . The transmitter/receiver in belt pack  22  is in receive mode. Belt pack  22  plugs into cradle  40  and the radio frequency signal is sent wirelessly at frequency F2 via secondary transceiver  60 , set in transmit mode, to ear set  44 .  
         [0060]    [0060]FIG. 8 is a block diagram of base station  18  showing the signal path in listen mode in more detail. Again, the audio signal is obtained from microphone  14  and amplified by amplifier  62  and sent to transmitter  64  for conversion to radio frequency. Note that receiver  66  of base station  18  is not utilized in listen mode.  
         [0061]    [0061]FIG. 9 is a block diagram of belt pack  22  showing the signal path in listen mode in more detail. The radio frequency signal is received by receiver  68 , converted to an audio signal, amplified by amplifier  70  and sent to a modular telephone connector for direct connection to cradle  40 . Note that transmitter  72  of belt pack  22  is not utilized in listen mode.  
         [0062]    [0062]FIG. 10 is a block diagram of secondary transceiver  60  of cradle  40  showing the signal path in listen mode in more detail. The audio signal is obtained, via a modular telephone connector, from belt pack  22  (FIG. 9) and is amplified in amplifier  74  and converted to radio frequency and sent via frequency F2 via transmitter  76  to ear set  44 . Note that receiver  78  of secondary transceiver  60  is not utilized in listen mode.  
         [0063]    [0063]FIG. 11 is a diagrammatic illustration of the signal path of an embodiment of the intercom system of the present invention in “talk” mode, i.e., when an ear set  44  wearer is talking to the person in the ordering vehicle. In talk mode, ear set  44  picks up the voice of ear set  44  wearer and wirelessly transmits at frequency F2 to secondary transceiver  60  in cradle  40 . Transceiver  60  in cradle  40  receives the radio frequency signal from ear set  44  and sends an audio signal to belt pack  22 , plugged into cradle  40 . The transmitter/receiver in belt pack  22  is in talk mode. The signal is then transmitted via wireless frequency F1 to base station  18 . Base station  18  receives the radio frequency signal and sends an audio signal via cable  16  (FIG. 3) to speaker  12 , remotely located near a menu board.  
         [0064]    [0064]FIG. 12 is a block diagram of secondary transceiver  60  of cradle  40  showing the signal path in talk mode in more detail. The wireless radio frequency signal at frequency F2 is obtained from ear set  44  by receiver  78 , converted to audio and amplified in amplifier  80 . In a preferred embodiment, the audio signal is then sent to two places. First, the audio signal is sent, via a modular telephone connector, to belt pack  22  (FIG. 13). Second, the audio is also sent to transmitter  76  of secondary transceiver  60  for transmission at a third frequency.  
         [0065]    [0065]FIG. 13 is a block diagram of belt pack  22  showing the signal path in talk mode in more detail. The audio signal is received via a modular telephone connector, amplified in amplifier  82  and sent to transmitter  72  for radio frequency transmission at wireless frequency F1 to base station  18 . Note that receiver  68  of belt pack  22  is not utilized in talk mode.  
         [0066]    [0066]FIG. 14 is a block diagram of base station  18  showing the signal path in talk mode in more detail. The radio frequency signal is obtained by receiver  66 , converted to audio and, in a preferred embodiment, is sent to two places. First, the audio signal is amplified in amplifier  84  and sent, via cable  16  (FIG. 3) to remotely located speaker  12 . Second, the audio signal is sent to transmitter  64  for conversion to radio frequency at frequency F1 for transmission to other belt packs  22  which may be utilized in a multiple belt pack  22  installation.  
         [0067]    In an embodiment of the present invention, it is recognized that, particularly in new installations not already having existing belt packs  22 , that the functionality of base station  18  and belt pack  22  could be combined into a single unit. In this situation, it would not be necessary to use a first wireless frequency F1 since the requirement for wireless communication between a separate base station  18  and a separate belt pack  22  would be eliminated. As shown in FIG. 15, combined base station  86  communicates with speaker  12  and microphone  14  as described above. However, instead of communicating with belt pack  22  on wireless frequency F1, combined base station  86  may communicate directly with ear sets  44  on wireless frequency F2. Many of the advantages of the present invention arising from the dichotomy in “listen mode range” and “talk mode range” are still obtained and one less component is required. The disadvantage, of course, is that retrofitting into existing installations is more difficult.  
         [0068]    Alternatively, it is also recognized that the function of secondary transceiver  60  could be located inside belt pack  22  allowing belt pack  22  to wireless communicate on wireless frequency F2 with ear sets  44 . The advantage would be in the elimination of a component. Again, the disadvantage is that retrofitting existing installations is more difficult.  
         [0069]    The present invention provides a significant comfort advantage. The relatively small ear set  44  can be clipped onto the ear and typically weighs less than one ounce (28 grams). This size and weight are similar to wireless ear pieces commonly used with a mobile telephone in automobiles.  
         [0070]    The present invention also provides a significant advantage in being unobtrusive. The relatively small ear set  44  can be hidden in the hair and generally not noticeable by observers making the invention useful to users who would not normally accept a standard prior art head set.  
         [0071]    The present invention also provides a significant cost advantage. The relatively small ear set  44  is expected to cost less than one-half of the cost of a prior art belt pack  22 . Since a single belt pack  22  can communicate with a plurality of ear sets  44 , many more people in retail establishment  10  can wear ear sets  44  and have access to the communication link increasing efficiency of operation for retail establishment  10  and potentially lowering prices for customers.  
         [0072]    The present invention also provides a significant advantage in being able to be easily retrofitted into existing installations currently utilizing conventional prior base station/belt pack/head set technology.  
         [0073]    While the invention has been mostly described in terms of a retail establishment having a drive up lane, particularly a restaurant or a fast food type restaurant, it is recognized and understood the present invention may find utility in other intercom environments in which one or more people communicate with one or more people at a remote location. It is neither necessary nor required that the people or the equipment be located in a particular building, or any building, or be performing any particular function.  
         [0074]    While the invention has been described mostly in terms of employees of a retail establishment, it is recognized and understood that the present invention is useful in other environments in which people communicating over the intercom would not necessarily be employees of the same organization, or any organization.  
         [0075]    While the invention has been mostly described in terms of communication between a remotely located person presenting an order to an order taker located inside a restaurant, it is recognized and understood that the utility of the present invention is not limited to order takers and could be utilized by any person communicating with another individual at a remote location.  
         [0076]    Various modifications and alterations of this invention will be apparent to those skilled in the art without departing from the scope and spirit of this invention. It should be understood that this invention is not limited to the illustrative embodiments set forth above.