JPS63185230A - Radio receiver adapter - Google Patents

Abstract

PURPOSE:To listen to public address without modifying a general radio receiver, by constituting a device in such a way that a received FM signal for the public address is converted to a general broadcasting wave, and it is transmitted to a radio receiver with electromagnetic coupling. CONSTITUTION:A radio receiver adapter 1 inputs the FM signal Fi transmitted from the antenna 2a of a transmitter 2 for the public address to a terminal 1b via an antenna 1a. An inputted FM signal Fi is converted to a voice signal Fa at an RF module 3a and a detector 3b, and is sent to an AM modulator 4 and an FM modulator 7, and corresponding to the operation of a power source switch 10, an AMRF signal Fo or an FMRF signal F'o is sent to the terminal 5a of an AM output part 5 or the terminal 8a of an FM output part 8. An AM radio 6 is housed in the receiver housing part 1c of the radio receiver adapter 1, and also, the coil L2 of an antenna circuit of the AM radio 6 is coupled with the coil L1 of the AM output part 5. Meanwhile, if an FM radio 9 is housed in the housing part 1c, the coil L2 of the FM radio 9 is coupled with the coil L3 of the FM output part 8, and either case, it is possible to receive the FM signal Fi.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a radio receiver adapter, and more particularly to a radio receiver adapter used in the Kinai Broadcasting Receiving System.

[Technical background of the invention and its problems]

When simultaneously transmitting the same information to people dispersed over a wide area at a baseball stadium, racetrack, golf course, amusement park, or event venue, a plurality of loudspeakers are usually used. However, the loudspeaker broadcasts were noisy;
It is difficult to hear in a dark environment, and in a quiet environment, it becomes a noise for third parties outside the venue, so a method has been proposed in which the public address is broadcast wirelessly and attendees can listen to it using regular earphone-type pocket radios.

However, since ordinary earphone-type portable radios are designed to receive broadcast waves with strong electric fields, they have low sensitivity, and it would be a violation of the Radio Law if they were to transmit with antenna power that would provide the electric field strength necessary for this type of radio. Become. Therefore, the facility operator will broadcast using antenna power (hereinafter referred to as weak radio waves) pursuant to Article 6, Paragraph 1 of the Radio Law Enforcement Regulations. The range that can be received by ordinary earphone-type portable radios when broadcasting using weak radio waves is limited to several tens of meters, so in the case of large facilities, there are disadvantages such as the need to install a large number of weak radio wave transmitting equipment. Furthermore, when using the same frequency, there are technical problems such as the need to synchronize with each other using weak radio waves, which makes it impractical regardless of whether it is a fixed venue or a temporary venue.

[Object of the Invention] The present invention has been made in view of the above-mentioned points, and provides a radio reception device that allows a normal relatively insensitive and inexpensive earphone-type portable radio to be used as a high-sensitivity receiver for public address broadcasting. The purpose is to provide machine adapters.

[Summary of the invention]

The radio receiver adapter according to the present invention receives and detects a frequency modulated signal using a highly sensitive receiving circuit to obtain a low frequency signal. Using this low frequency signal, a medium wave band modulation signal and a very high frequency band modulation signal are generated, and through electromagnetic coupling, an AM radio receiver can be called an FM radio receiver or simply an AM radio.
The signal is sent to the antenna circuit of an FM radio. The AM radio or FM radio used may be for normal general broadcast reception, and since it is M-coupled, there is no need to provide special signal exchange means such as a plug jack between it and the radio receiver adapter.

[Embodiments of the invention]

EMBODIMENT OF THE INVENTION Hereinafter, one embodiment of the radio receiver adapter according to the present invention will be described in detail with reference to the drawings.

In FIG. 1, 1 is a radio receiver adapter. The radio receiver adapter 1 receives an FM signal F1 transmitted from an antenna 2a of an FM transmitter 2 for public address broadcasting through an antenna 1a to a terminal 1b.

FM signal Fi is a radio wave from a wireless station that does not require a license as stipulated in Article 6, Paragraph 2 of the Radio Law Enforcement Regulations, and uses, for example, 40.68W (z).The antenna power is 200W at a distance of 500m.
It is μη. The radio receiver adapter 1 includes an FM receiving section 3 as a frequency modulated signal receiving means, an AM modulator 4 as a medium wave band RF signal converting means, an FM modulator 7 as a very high frequency band RF signal converting means, and an AM output section 5 as an electromagnetic converting means. and an FM output section 8. The FM receiving section 3 includes an RF module 3a and a detector 3b. The FM signal Fi input to the terminal 1b is converted into an audio signal Fa by the RF module 3a and the detector 3b, and sent to the AM modulator 4 and the FM modulator 7. The AM modulator 4 and the FMK modulator 7 are selectively supplied with power via the switch 10, so that depending on the operation of the switch 10, either the F signal Fo or the FMRF
The signal F'o is sent to the terminal 5a of the AM output section 5 or the FM output section 8
The signal is sent to terminal 8a.

Receiver storage part 1 of radio receiver adapter l shown in Fig. 2
When the eiCAM radio 6 is stored, the coil L of the antenna circuit consisting of the coil L2 of the AM radio 6 and the capacitor C2
2 and the coil Ll of the AM output section 5 to be coupled with the AM
The AM radio 6 tuned to the RF signal Fo can receive the FM signal Fi.

On the other hand, when the CFM radio 9 is stored in the receiver storage section 1cl, the coil L4 of the FM radio 9 and the coil L3 of the FM output section 8 are M-coupled.
You can receive FM signal Fi with M Radio 9.

The frequency of the FM signal Fi is preferably a VHF band or a UHF band outside the cover band of the FM radio 9, taking into account the shape of the antenna 2a of the FM transmitter 2 for public broadcasting.

〔Effect of the invention〕

The radio receiver adapter according to the present invention is characterized in that it is configured to convert a received FM signal for public broadcasting into a normal broadcast wave and transmit it to a radio receiver by electromagnetic coupling. Therefore, it is possible to listen to in-house broadcasts without modifying a general radio receiver.

Further, when a means for integrating the radio receiver adapter and the radio receiver is provided, the electromagnetic coupling is stabilized.

Further, if a switch means is provided to make either the AM side or the FM side inactive, it is possible to reduce power consumption and prevent the occurrence of spurious signals.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a radio receiver adapter according to the present invention, and FIG. 2 is a perspective view of FIG. 1. Code 1 in the diagram
is a radio receiver adapter, 2 is a public address transmitter, 3 is an FM receiver, 3a is an RF module, 3b is a medical examiner, 4
is AM modulation section, 5 is AM output section, 6 is AM radio, 7 is FM modulation section, 8 is FM output section, 9 is FM radio, 10 is switch, 11 is power supply, CZm"4 is capacitor, Ll
. Lx sLs *L4 is a coil. Patent applicant Yaesu Musen Co., Ltd. Figure 1

Claims (3)

[Claims] (1) In a radio receiver adapter that sends a medium wave band RF signal or a very high frequency band RF signal to the antenna circuit of a medium wave band radio receiver and a very high frequency band radio receiver, a frequency band different from the medium wave band and the very high frequency band is used. a frequency modulated signal receiving means for receiving a frequency modulated signal to generate an audio signal; a medium wave band RF signal converting means for converting the audio signal obtained by the frequency modulated signal receiving means into the medium wave band RF signal; Very high frequency band RF that converts the audio signal into the above-mentioned very high frequency band RF signal
It is characterized by comprising a signal conversion means and an electromagnetic conversion means for electromagnetically converting a medium wave band or very high frequency band RF signal, and configured to send the RF signal to the antenna circuit of the radio receiver via electromagnetic coupling. radio receiver adapter. (2) In the statement of claim 1, it is stated that means for integrating the radio receiver adapter and the medium wave band radio receiver or the very high frequency band radio receiver is provided so that the electromagnetic coupling is stabilized. Features a radio receiver adapter. (3) The electromagnetic conversion means is provided with a switch means for activating either the medium wave band RF signal electromagnetic conversion means or the short wave band RF signal electromagnetic conversion means, and the RF signal is transmitted to the corresponding radio receiver. 3. The radio receiver adapter according to claim 1, wherein the radio receiver adapter is configured to transmit.