CA2220312C - Radio receiver and rebroadcaster - Google Patents
Radio receiver and rebroadcaster Download PDFInfo
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- CA2220312C CA2220312C CA002220312A CA2220312A CA2220312C CA 2220312 C CA2220312 C CA 2220312C CA 002220312 A CA002220312 A CA 002220312A CA 2220312 A CA2220312 A CA 2220312A CA 2220312 C CA2220312 C CA 2220312C
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Classifications
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- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D1/00—Detergent compositions based essentially on surface-active compounds; Use of these compounds as a detergent
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- C—CHEMISTRY; METALLURGY
- C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
- C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
- C11D2111/00—Cleaning compositions characterised by the objects to be cleaned; Cleaning compositions characterised by non-standard cleaning or washing processes
- C11D2111/10—Objects to be cleaned
- C11D2111/14—Hard surfaces
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- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
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- Circuits Of Receivers In General (AREA)
Abstract
A radio receiver and rebroadcaster comprises a first receiver for FM Radio signals, a frequency synthesizer and microprocessor controller, a subcarrier select filter and amplifier which filters out all signals from the composite baseband signal except for a desired subcarrier signal, a second receiver which converts the subcarrier signal to a recovered audio signal, a lowpass active filter which filters the recovered audio signal, a varactor modulator and rebroadcast transmitter which receives the filtered audio signal and varies the frequency of the signal emanating from the rebroadcast transmitter proportional to an audio wave form, and a band selector which is controlled by the microprocessor controller for controlling gain in the varactor modulator and for selecting a rebroadcasting frequency.
The microprocessor controller provides tuning information to the frequency synthesizer, and the frequency synthesizer cooperates with the first receiver to provide a composite baseband signal. The subcarrier signal is selected by the microprocessor controller.
The microprocessor controller provides tuning information to the frequency synthesizer, and the frequency synthesizer cooperates with the first receiver to provide a composite baseband signal. The subcarrier signal is selected by the microprocessor controller.
Description
RADIO.P0003 RADIO RECEIVER AND REBROADCASTER
FIELD OF THE INVENTION
The present invention relates to a combination 5 receiver and rebroadcaster for FM Radio signals, especially for receiving and rebroadcasting so-called SCA or SCMO subcarrier signals.
BACKGROUND TO THE INVENTION
As is known, radio signals from FM radio stations 10 comprise composite signals. For example, the composite signal contains the left and right audio information from 20 Hz up to 15 kHz, a pilot carrier (typically 19 kHz) and a double side band suppressed carrier, (typically from 23 kHz to 53 kHz centred at 38 kHz).
Radio stations may be authorized to also broadcast signals known in the U.S.A. as Subsidiary Communication Authorization (SCA) signals. In Canada, such signals are known as Subsidiary Communication Multiplex Operation (SCMO), and in Australia, such signals are 20 known as Auxiliary Communication Services (ACS), but for reference purposes herein, such signals are referred to as SCA signals. If the main radio channel is broadcasting SCA signals, then the composite signal also contains a subcarrier, typically at 67 kHz and/or 92 25 kHz. As is known, the SCA subcarriers are narrow band FM signals, usually with a deviation of + 7.5 kHz and are not used for high fidelity service. The subcarriers are usually only about 10% of the signal deviation that a radio station transmits, which makes the subcarriers 30 unusually weak and inherently noisy. They are suitable, however, for programs to limited audiences, e.g. ethnic broadcasting. Use of the SCA subcarriers is a cost-effective way of transmitting programs to limited audiences because it is not necessary to build a 35 transmission system specifically for such limited-distribution programming. In addition, such signals may be carried into homes by means of cable systems, typically used for TV transmission.
As radio receivers, which are commonly available in stores, are adapted and manufactured to receive only the main signals, it is not possible to pick up the subcarriers on such radio receivers. In order for a person to listen to the subcarrier signal, it is 5 necessary to purchase a specially adapted single channel radio receiver. Commercially, such receivers are only able to receive one signal. This creates a number of difficulties for the person listening to the subcarrier signal.
The disadvantages are now described and exemplified with respect to foreign-language subcarrier signals.
For example, in Toronto, Canada, the Tamil-language subcarrier signal may be a 67 kHz signal subcarrier on a main signal of 100.5 MHz. In Montreal, Canada, if there 15 is SCA being broadcast, the Tamil-language subcarrier signal may be a 92 kHz subcarrier signal on a 89.7 MHz main signal. A Tamil-language listener in Toronto would have a radio receiver adapted to play the Toronto subcarrier signal, and thus the listener would be unable 20 to take the radio receiver to Montreal and listen to the Montreal subcarrier signal without having a separate radio receiver to do so. In another example Greek-language listeners in Toronto have three radio stations that they can listen to, but they need three separate 25 radios, each attuned to a particular subcarrier signal.
As will be appreciated, for the listener this can be expensive and inconvenient.
In addition, although the single channel radios can be used in an automobile, it presents several problems.
30 Among them is the fact that there is poor sound quality and volume, and the radio is bulky and awkward to use in the automobile. Even with single channel radios, there is a need to improve the quality and volume of the sound, and to enhance the portability of the radio For all of the above reasons and more, the current situation is unsatisfactory and the present invention is intended to overcome the problems.
SUMMARY OF THE INVENTION
Accordingly, the invention provides a receiver and rebroadcaster which comprises:
(a) a first receiver for FM signals;
(b) a frequency synthesizer and microprocessor controller, said microprocessor controller providing tuning information to the frequency synthesizer, and the frequency synthesizer cooperates with the first receiver to provide a composite baseband signal;
(c) a subcarrier select filter and amplifier which filters out essentially all signals from the composite baseband signal except for a desired subcarrier signal, said subcarrier signal being selected by the microprocessor controller;
(d) a second receiver which converts the subcarrier signal to a recovered audio signal;
(e) a lowpass active filter which filters the recovered audio signal;
(f) a varactor modulator and rebroadcast 20 transmitter which receives the filtered audio signal and varies the frequency of the signal emanating from the rebroadcast transmitter proportional to an audio wave form; and (g) a band selector which is controlled by the 25 microprocessor controller for controlling gain in the varactor modulator and for selecting a rebroadcasting frequency.
In one embodiment, the first receiver is adapted to receive FM signals from radio signals.
In another embodiment, the first receiver is adapted to receive FM signals from cable transmissions.
In a further embodiment, the first receiver has a selector for receive FM signals from either radio signals or from a cable transmission.
In one embodiment, the microprocessor controller and frequency synthesizer is set to select subcarrier signals at one of several predetermined frequencies, for example either 67 kHz or 92 kHz.
In another embodiment the microprocessor controller is manually settable with user selectable switches which select combinations of a main channel carrier and a 5 subcarrier.
In a further embodiment, the microprocessor controller is settable with a scanner and locking means for selecting a particular combination of main channel carrier and subcarrier.
In yet another embodiment the rebroadcasting frequency may be in an FM band or in an AM band.
The invention also provides a receiver and rebroadcaster which comprises:
(a~ a first receiver for FM signalsi (b) a frequency synthesizer which cooperates with the first receiver to provide a composite baseband signal;
(c) a subcarrier select filter and amplifier which filters out all signals from the composite baseband 20 signal except for a desired preselected subcarrier signal;
(d) a second receiver which converts the subcarrier signal to a recovered audio signal;
(e) a lowpass active filter which filters the 25 recovered audio signal;
(f) a varactor modulator and rebroadcast transmitter which receives the filtered audio signal and varies the frequency of the signal emanating from the rebroadcast transmitter proportional to an audio wave 30 form; and (g) a band selector which is controlled by a microprocessor controller for controlling gain in the varactor modulator and for selecting a rebroadcasting frequency.
The drawing is a schematic block diagram of a multi-channel receiver/rebroadcaster of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The basic premise of the present invention is that the composite signal from a radio station or cable 5 service is received and the SCA subcarrier is converted to a frequency suitable for rebroadcasting. The rebroadcasted signal is directed to a frequency on a regular radio receiver which is not assigned to any other radio station. In addition, the rebroadcasted 10 signal is sufficiently strong to be picked up by a regular AM or FM radio receiver within a limited radius of the receiver/rebroadcaster of the present invention but sufficiently weak not to interfere with reception by a neighbour. For example, it would be sufficiently 15 strong to be picked up by any radio in a normal household but sufficiently weak that it could not be picked up by a neighbour in a house or apartment nearby.
It will be understood that in many jurisdictions, the receiver/rebroadcaster may need to comply with 20 governmental regulations regarding rebroadcasting.
The signal that is allowed to pass through the subcarrier select filter and amplifier is fed into a second receiver. This second receiver converts the subcarrier to an intermediate frequency, e.g. 455 kHz, 25 by means of heterodyning a second local oscillator with the subcarrier. The second receiver also contains a narrow bandpass filter for the intermediate frequency and a quadrature detector which recovers the audio information. In a multi-channel receiver and 30 rebroadcaster, the second local oscillator frequency is selected by the microprocessor using the user selectable switches, e.g. dip switches. In a single channel receiver and rebroadcaster, the first and second local oscillator frequencies are preselected. The recovered 35 audio signal is then coupled to a lowpass active filter, e.g. a seventh order lowpass active filter. This filtering is required because there are many high frequency components in the recovered audio signal.
After filtering through the lowpass active filter, the signal may be split into two paths. One path is to an audio power amplifier which allows the user to connect 5 headphones or a speaker. This is not essential for the present invention, although it is a desirable option for the user. A second path is to a varactor modulator which varies a rebroadcast transmitter frequency proportional to the audio waveform. The microprocessor 10 also controls a band select circuit which is required in order to avoid rebroadcasting onto the main channel that contains the SCA signal. The microprocessor also controls the varactor modulator gain. This is required, in order to maintain the + 75 kHz frequency deviation 15 standard for commercial FM radio receivers. It is usually not necessary for the rebroadcast transmitter to use an antenna to radiate the signal, as the signal is intended for FM radio receivers in close proximity, e.g.
in the home or in an automobile. It will also be 20 understood that although rebroadcasting for reception on an FM radio receiver is preferred, the present invention could be adapted to rebroadcast onto an AM band frequency or for reception by any other suitable receiver, e.g. a television set.
The microcontroller has software which initializes the system. Additionally, after the user has selected a frequency with the switches or with the scanner, the software selects the appropriate subcarrier circuit, e.g. 67 kHz or 92 kHz carrier. It also decodes the 30 frequency of the broadcasting radio station and programmes the frequency synthesizer. In addition, the software is used to provide the appropriate rebroadcasting frequency and selects the appropriate circuit.
The receiver/rebroadcaster of the present invention is powered by a power supply which is usually a 12v power supply. For example, the power may be provided by .
a transformer from the main electricity or from a car cigarette lighter outlet or a battery. The power is fed into a filter and voltage regulator to minimize any noise that may be generated by a car ignition or various 5 other sources, as well as maintaining a stable voltage level to supply the receiver rebroadcaster.
The composite signal transmitted by a radio station is received by the antenna and first receiver and is then coupled to a subcarrier select filter and 10 amplifier. The function of the subcarrier select filter and amplifier is to filter out undesired signals from the composite signal. This is achieved by high Q passive elements arranged in two bandpass filters, as will be understood by one skilled in the art. In a multi-15 channel receiver and broadcaster the desired filter isselected by a microprocessor after the user has selected a particular desired signal using user selectable switches, e.g. dip switches. It will be understood that the user selectable switches may be replaced by a 20 scanner with a locking device. In this instance, the user would allow the scanner to scan from one subcarrier frequency to another and when the desired station is reached, e.g. a Tamil-language frequency, then the microprocessor would lock the scanner to that particular 25 subcarrier frequency. For example, the scanner may be set up to first scan the 67 kHz subcarrier band and then the 92 kHz subcarrier band and then return to scanning the 67 kHz band of the next main channel until the microprocessor locks in a particular combination of main frequency and subcarrier frequency. The scanner may also be associated with a memory device for memorizing several subcarrier signals of interest to the user.
Switches and scanners may be dispensed with for a single channel receiver and rebroadcaster because the 35 main channel and subcarrier frequencies would be preselected.
~ hen radio signals are transmitted by cable, it is common for the cable service to transmit the signal on a different frequency than the original radio signal. For known radios adapted for picking up SCA signals, it is therefore not possible to connect them to a cable 5 service and expect to receive the broadcast on the original frequency. With an embodiment of the present invention which has a scanner, the scanner will automatically search out the frequency assigned by the cable transmitter. This is an additional advantage of 10 the present invention which cannot be addressed by prior SCA radios.
As will be clear from the above, a user would only require one of the multi-channel receiver/rebroadcasters of the present invention in order to be able to listen 15 to any number of the programs carried by the subcarriers. In addition, the present receiver/rebroadcaster allows a user to take the receiver/rebroadcaster from one community to another and be able to listen to programs of choice as long as the 20 dip switch combination is known for that community, or if the receiver/rebroadcaster is equipped with a scanner, then by using the scanner. The present invention is particularly useful in home environments and for use in automobiles.
FIELD OF THE INVENTION
The present invention relates to a combination 5 receiver and rebroadcaster for FM Radio signals, especially for receiving and rebroadcasting so-called SCA or SCMO subcarrier signals.
BACKGROUND TO THE INVENTION
As is known, radio signals from FM radio stations 10 comprise composite signals. For example, the composite signal contains the left and right audio information from 20 Hz up to 15 kHz, a pilot carrier (typically 19 kHz) and a double side band suppressed carrier, (typically from 23 kHz to 53 kHz centred at 38 kHz).
Radio stations may be authorized to also broadcast signals known in the U.S.A. as Subsidiary Communication Authorization (SCA) signals. In Canada, such signals are known as Subsidiary Communication Multiplex Operation (SCMO), and in Australia, such signals are 20 known as Auxiliary Communication Services (ACS), but for reference purposes herein, such signals are referred to as SCA signals. If the main radio channel is broadcasting SCA signals, then the composite signal also contains a subcarrier, typically at 67 kHz and/or 92 25 kHz. As is known, the SCA subcarriers are narrow band FM signals, usually with a deviation of + 7.5 kHz and are not used for high fidelity service. The subcarriers are usually only about 10% of the signal deviation that a radio station transmits, which makes the subcarriers 30 unusually weak and inherently noisy. They are suitable, however, for programs to limited audiences, e.g. ethnic broadcasting. Use of the SCA subcarriers is a cost-effective way of transmitting programs to limited audiences because it is not necessary to build a 35 transmission system specifically for such limited-distribution programming. In addition, such signals may be carried into homes by means of cable systems, typically used for TV transmission.
As radio receivers, which are commonly available in stores, are adapted and manufactured to receive only the main signals, it is not possible to pick up the subcarriers on such radio receivers. In order for a person to listen to the subcarrier signal, it is 5 necessary to purchase a specially adapted single channel radio receiver. Commercially, such receivers are only able to receive one signal. This creates a number of difficulties for the person listening to the subcarrier signal.
The disadvantages are now described and exemplified with respect to foreign-language subcarrier signals.
For example, in Toronto, Canada, the Tamil-language subcarrier signal may be a 67 kHz signal subcarrier on a main signal of 100.5 MHz. In Montreal, Canada, if there 15 is SCA being broadcast, the Tamil-language subcarrier signal may be a 92 kHz subcarrier signal on a 89.7 MHz main signal. A Tamil-language listener in Toronto would have a radio receiver adapted to play the Toronto subcarrier signal, and thus the listener would be unable 20 to take the radio receiver to Montreal and listen to the Montreal subcarrier signal without having a separate radio receiver to do so. In another example Greek-language listeners in Toronto have three radio stations that they can listen to, but they need three separate 25 radios, each attuned to a particular subcarrier signal.
As will be appreciated, for the listener this can be expensive and inconvenient.
In addition, although the single channel radios can be used in an automobile, it presents several problems.
30 Among them is the fact that there is poor sound quality and volume, and the radio is bulky and awkward to use in the automobile. Even with single channel radios, there is a need to improve the quality and volume of the sound, and to enhance the portability of the radio For all of the above reasons and more, the current situation is unsatisfactory and the present invention is intended to overcome the problems.
SUMMARY OF THE INVENTION
Accordingly, the invention provides a receiver and rebroadcaster which comprises:
(a) a first receiver for FM signals;
(b) a frequency synthesizer and microprocessor controller, said microprocessor controller providing tuning information to the frequency synthesizer, and the frequency synthesizer cooperates with the first receiver to provide a composite baseband signal;
(c) a subcarrier select filter and amplifier which filters out essentially all signals from the composite baseband signal except for a desired subcarrier signal, said subcarrier signal being selected by the microprocessor controller;
(d) a second receiver which converts the subcarrier signal to a recovered audio signal;
(e) a lowpass active filter which filters the recovered audio signal;
(f) a varactor modulator and rebroadcast 20 transmitter which receives the filtered audio signal and varies the frequency of the signal emanating from the rebroadcast transmitter proportional to an audio wave form; and (g) a band selector which is controlled by the 25 microprocessor controller for controlling gain in the varactor modulator and for selecting a rebroadcasting frequency.
In one embodiment, the first receiver is adapted to receive FM signals from radio signals.
In another embodiment, the first receiver is adapted to receive FM signals from cable transmissions.
In a further embodiment, the first receiver has a selector for receive FM signals from either radio signals or from a cable transmission.
In one embodiment, the microprocessor controller and frequency synthesizer is set to select subcarrier signals at one of several predetermined frequencies, for example either 67 kHz or 92 kHz.
In another embodiment the microprocessor controller is manually settable with user selectable switches which select combinations of a main channel carrier and a 5 subcarrier.
In a further embodiment, the microprocessor controller is settable with a scanner and locking means for selecting a particular combination of main channel carrier and subcarrier.
In yet another embodiment the rebroadcasting frequency may be in an FM band or in an AM band.
The invention also provides a receiver and rebroadcaster which comprises:
(a~ a first receiver for FM signalsi (b) a frequency synthesizer which cooperates with the first receiver to provide a composite baseband signal;
(c) a subcarrier select filter and amplifier which filters out all signals from the composite baseband 20 signal except for a desired preselected subcarrier signal;
(d) a second receiver which converts the subcarrier signal to a recovered audio signal;
(e) a lowpass active filter which filters the 25 recovered audio signal;
(f) a varactor modulator and rebroadcast transmitter which receives the filtered audio signal and varies the frequency of the signal emanating from the rebroadcast transmitter proportional to an audio wave 30 form; and (g) a band selector which is controlled by a microprocessor controller for controlling gain in the varactor modulator and for selecting a rebroadcasting frequency.
The drawing is a schematic block diagram of a multi-channel receiver/rebroadcaster of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The basic premise of the present invention is that the composite signal from a radio station or cable 5 service is received and the SCA subcarrier is converted to a frequency suitable for rebroadcasting. The rebroadcasted signal is directed to a frequency on a regular radio receiver which is not assigned to any other radio station. In addition, the rebroadcasted 10 signal is sufficiently strong to be picked up by a regular AM or FM radio receiver within a limited radius of the receiver/rebroadcaster of the present invention but sufficiently weak not to interfere with reception by a neighbour. For example, it would be sufficiently 15 strong to be picked up by any radio in a normal household but sufficiently weak that it could not be picked up by a neighbour in a house or apartment nearby.
It will be understood that in many jurisdictions, the receiver/rebroadcaster may need to comply with 20 governmental regulations regarding rebroadcasting.
The signal that is allowed to pass through the subcarrier select filter and amplifier is fed into a second receiver. This second receiver converts the subcarrier to an intermediate frequency, e.g. 455 kHz, 25 by means of heterodyning a second local oscillator with the subcarrier. The second receiver also contains a narrow bandpass filter for the intermediate frequency and a quadrature detector which recovers the audio information. In a multi-channel receiver and 30 rebroadcaster, the second local oscillator frequency is selected by the microprocessor using the user selectable switches, e.g. dip switches. In a single channel receiver and rebroadcaster, the first and second local oscillator frequencies are preselected. The recovered 35 audio signal is then coupled to a lowpass active filter, e.g. a seventh order lowpass active filter. This filtering is required because there are many high frequency components in the recovered audio signal.
After filtering through the lowpass active filter, the signal may be split into two paths. One path is to an audio power amplifier which allows the user to connect 5 headphones or a speaker. This is not essential for the present invention, although it is a desirable option for the user. A second path is to a varactor modulator which varies a rebroadcast transmitter frequency proportional to the audio waveform. The microprocessor 10 also controls a band select circuit which is required in order to avoid rebroadcasting onto the main channel that contains the SCA signal. The microprocessor also controls the varactor modulator gain. This is required, in order to maintain the + 75 kHz frequency deviation 15 standard for commercial FM radio receivers. It is usually not necessary for the rebroadcast transmitter to use an antenna to radiate the signal, as the signal is intended for FM radio receivers in close proximity, e.g.
in the home or in an automobile. It will also be 20 understood that although rebroadcasting for reception on an FM radio receiver is preferred, the present invention could be adapted to rebroadcast onto an AM band frequency or for reception by any other suitable receiver, e.g. a television set.
The microcontroller has software which initializes the system. Additionally, after the user has selected a frequency with the switches or with the scanner, the software selects the appropriate subcarrier circuit, e.g. 67 kHz or 92 kHz carrier. It also decodes the 30 frequency of the broadcasting radio station and programmes the frequency synthesizer. In addition, the software is used to provide the appropriate rebroadcasting frequency and selects the appropriate circuit.
The receiver/rebroadcaster of the present invention is powered by a power supply which is usually a 12v power supply. For example, the power may be provided by .
a transformer from the main electricity or from a car cigarette lighter outlet or a battery. The power is fed into a filter and voltage regulator to minimize any noise that may be generated by a car ignition or various 5 other sources, as well as maintaining a stable voltage level to supply the receiver rebroadcaster.
The composite signal transmitted by a radio station is received by the antenna and first receiver and is then coupled to a subcarrier select filter and 10 amplifier. The function of the subcarrier select filter and amplifier is to filter out undesired signals from the composite signal. This is achieved by high Q passive elements arranged in two bandpass filters, as will be understood by one skilled in the art. In a multi-15 channel receiver and broadcaster the desired filter isselected by a microprocessor after the user has selected a particular desired signal using user selectable switches, e.g. dip switches. It will be understood that the user selectable switches may be replaced by a 20 scanner with a locking device. In this instance, the user would allow the scanner to scan from one subcarrier frequency to another and when the desired station is reached, e.g. a Tamil-language frequency, then the microprocessor would lock the scanner to that particular 25 subcarrier frequency. For example, the scanner may be set up to first scan the 67 kHz subcarrier band and then the 92 kHz subcarrier band and then return to scanning the 67 kHz band of the next main channel until the microprocessor locks in a particular combination of main frequency and subcarrier frequency. The scanner may also be associated with a memory device for memorizing several subcarrier signals of interest to the user.
Switches and scanners may be dispensed with for a single channel receiver and rebroadcaster because the 35 main channel and subcarrier frequencies would be preselected.
~ hen radio signals are transmitted by cable, it is common for the cable service to transmit the signal on a different frequency than the original radio signal. For known radios adapted for picking up SCA signals, it is therefore not possible to connect them to a cable 5 service and expect to receive the broadcast on the original frequency. With an embodiment of the present invention which has a scanner, the scanner will automatically search out the frequency assigned by the cable transmitter. This is an additional advantage of 10 the present invention which cannot be addressed by prior SCA radios.
As will be clear from the above, a user would only require one of the multi-channel receiver/rebroadcasters of the present invention in order to be able to listen 15 to any number of the programs carried by the subcarriers. In addition, the present receiver/rebroadcaster allows a user to take the receiver/rebroadcaster from one community to another and be able to listen to programs of choice as long as the 20 dip switch combination is known for that community, or if the receiver/rebroadcaster is equipped with a scanner, then by using the scanner. The present invention is particularly useful in home environments and for use in automobiles.
Claims (5)
1. A receiver and rebroadcaster which comprises:
(a) a first receiver for FM signals;
(b) a frequency synthesizer and microprocessor controller, said microprocessor controller providing tuning information to the frequency synthesizer, to set to tune the first receiver and select subcarrier signals at predetermined frequencies to provide a composite baseband signal;
(c) a subcarrier select filter and amplifier which filters out all signals from the composite baseband signal except for a desired subcarrier signal, said subcarrier signal being selected by the microprocessor controller;
(d) a second receiver which converts the subcarrier signal to a recovered audio signal;
(e) a lowpass active filter which filters the recovered audio signal;
(f) a varactor modulator and rebroadcast transmitter which receives the filtered audio signal and varies the frequency of the signal emanating from the rebroadcast transmitter proportional to the filtered audio signal; and (g) a band selector which is controlled by the microprocessor controller for controlling gain in the varactor modulator and for selecting a rebroadcasting frequency.
(a) a first receiver for FM signals;
(b) a frequency synthesizer and microprocessor controller, said microprocessor controller providing tuning information to the frequency synthesizer, to set to tune the first receiver and select subcarrier signals at predetermined frequencies to provide a composite baseband signal;
(c) a subcarrier select filter and amplifier which filters out all signals from the composite baseband signal except for a desired subcarrier signal, said subcarrier signal being selected by the microprocessor controller;
(d) a second receiver which converts the subcarrier signal to a recovered audio signal;
(e) a lowpass active filter which filters the recovered audio signal;
(f) a varactor modulator and rebroadcast transmitter which receives the filtered audio signal and varies the frequency of the signal emanating from the rebroadcast transmitter proportional to the filtered audio signal; and (g) a band selector which is controlled by the microprocessor controller for controlling gain in the varactor modulator and for selecting a rebroadcasting frequency.
2. A receiver and broadcaster according to Claim 1 wherein the predetermined frequencies are 67 kHz and 92 kHz.
3. A receiver and broadcaster according to Claim 1 wherein the microprocessor controller is either i) manually settable with user selectable switches which select combinations of a main channel carrier and a subcarrier or ii) settable with a scanner and locking means for selecting a particular combination of main channel carrier and subcarrier.
4. A receiver and rebroadcaster which comprises:
(a) a first receiver for FM signals;
(b) a frequency synthesizer which tunes the first receiver to a desired channel on an FM band which provides a composite baseband signal;
(c) a subcarrier select filter and amplifier which filters out all signals from the composite baseband signal except for a desired preselected subcarrier signal;
(d) a second receiver which converts the subcarrier signal to a recovered audio signal;
(e) a lowpass active filter which filters the recovered audio signal;
(f) a varactor modulator and rebroadcast transmitter which receives the filtered audio signal and varies the frequency of the signal emanating from the rebroadcast transmitter proportional to the filtered audio signal; and (g) a band selector which is controlled by a microprocessor controller for controlling gain in the varactor modulator and for selecting a rebroadcasting frequency.
(a) a first receiver for FM signals;
(b) a frequency synthesizer which tunes the first receiver to a desired channel on an FM band which provides a composite baseband signal;
(c) a subcarrier select filter and amplifier which filters out all signals from the composite baseband signal except for a desired preselected subcarrier signal;
(d) a second receiver which converts the subcarrier signal to a recovered audio signal;
(e) a lowpass active filter which filters the recovered audio signal;
(f) a varactor modulator and rebroadcast transmitter which receives the filtered audio signal and varies the frequency of the signal emanating from the rebroadcast transmitter proportional to the filtered audio signal; and (g) a band selector which is controlled by a microprocessor controller for controlling gain in the varactor modulator and for selecting a rebroadcasting frequency.
5. A receiver and broadcaster according to Claim 1 or Claim 4 which has a selector for selecting the FM signal form a radio source or a cable source.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US6500697P | 1997-11-10 | 1997-11-10 | |
| US60/065,006 | 1997-11-10 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2220312A1 CA2220312A1 (en) | 1998-03-01 |
| CA2220312C true CA2220312C (en) | 1999-11-09 |
Family
ID=22059717
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002220312A Expired - Fee Related CA2220312C (en) | 1997-11-10 | 1998-01-20 | Radio receiver and rebroadcaster |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP1051470A1 (en) |
| JP (1) | JP2001522931A (en) |
| CA (1) | CA2220312C (en) |
| WO (1) | WO1999024539A1 (en) |
Families Citing this family (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AR017744A1 (en) * | 1999-02-08 | 2001-09-12 | Procter & Gamble | POLYMERIC GLYCOLS AND DIOLES FOR IMPROVED DETERGENT COMPOSITIONS FOR THE WASHING OF VAJILLA |
| WO2000063333A1 (en) * | 1999-04-19 | 2000-10-26 | The Procter & Gamble Company | Detergent composition comprising anti-hazing agent |
| US6653274B1 (en) | 1999-09-27 | 2003-11-25 | The Proctor & Gamble Company | Detergent composition comprising a soil entrainment system |
| WO2002008370A2 (en) * | 2000-07-19 | 2002-01-31 | The Procter & Gamble Company | Cleaning composition |
| WO2002008371A2 (en) * | 2000-02-17 | 2002-01-31 | The Procter & Gamble Company | Cleaning composition |
| MXPA03000488A (en) * | 2000-07-19 | 2003-06-24 | Procter & Gamble | Gel form automatic dishwashing compositions, methods of preparation and use thereof. |
| ATE350453T1 (en) * | 2000-07-19 | 2007-01-15 | Procter & Gamble | CLEANING SUPPLIES |
| JP4855022B2 (en) * | 2005-09-02 | 2012-01-18 | 花王株式会社 | Dishwashing composition for machine washing |
| JP4937728B2 (en) * | 2006-12-20 | 2012-05-23 | 花王株式会社 | Dishwashing composition for machine washing |
| JP5234568B2 (en) * | 2007-03-29 | 2013-07-10 | 株式会社Ａｄｅｋａ | Dishwashing detergent composition and precleaning detergent composition |
| EP2940116B1 (en) * | 2014-04-30 | 2018-10-17 | The Procter and Gamble Company | Detergent |
| JP6188236B2 (en) * | 2014-05-15 | 2017-08-30 | ライオン株式会社 | Liquid detergent and method for producing the same |
| JP2016145307A (en) * | 2015-02-09 | 2016-08-12 | 花王株式会社 | Detergent composition for liquid automatic dishwasher |
| JP7086585B2 (en) * | 2017-12-13 | 2022-06-20 | 花王株式会社 | How to clean dishes and / or hard items around the kitchen |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU463998B2 (en) * | 1971-04-12 | 1975-07-28 | Colgate-Palmolive Company | Cleaning composition with stabilized perfume |
| US4556509A (en) * | 1984-10-09 | 1985-12-03 | Colgate-Palmolive Company | Light duty detergents containing an organic diamine diacid salt |
| EP0232092A3 (en) * | 1986-01-28 | 1988-08-17 | Robert Goldman | Compositions and methods for removing tarnish from household articles |
| DD266805A1 (en) * | 1987-10-20 | 1989-04-12 | Leuna Werke Veb | CLEANER FOR DISHWASHERS |
| AU635774B2 (en) * | 1989-10-10 | 1993-04-01 | Colgate-Palmolive Company, The | Nonaqueous liquid automatic dishwasher detergent composition containing a dual bleach system |
| EP0588413A1 (en) * | 1992-09-15 | 1994-03-23 | Unilever N.V. | Detergent composition |
| GB9423234D0 (en) * | 1994-11-24 | 1995-01-04 | Unilever Plc | Cleaning compositions and their use |
| GB9423952D0 (en) * | 1994-11-24 | 1995-01-11 | Unilever Plc | Cleaning compositions and their use |
| BR9707951A (en) * | 1996-03-07 | 1999-07-27 | Procter & Gamble | Detergent compositions comprising improved amylases |
| DE59710275D1 (en) * | 1996-03-26 | 2003-07-17 | Basf Ag | IMPROVED DETERGENTS AND DISHWASHER |
-
1998
- 1998-01-20 CA CA002220312A patent/CA2220312C/en not_active Expired - Fee Related
- 1998-11-06 WO PCT/US1998/023657 patent/WO1999024539A1/en not_active Application Discontinuation
- 1998-11-06 EP EP98956645A patent/EP1051470A1/en not_active Withdrawn
- 1998-11-06 JP JP2000520535A patent/JP2001522931A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| CA2220312A1 (en) | 1998-03-01 |
| JP2001522931A (en) | 2001-11-20 |
| EP1051470A1 (en) | 2000-11-15 |
| WO1999024539A1 (en) | 1999-05-20 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |