JPH0523525B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to an earphone type radio receiver.

Background technology and its problems As a radio receiver exclusively for earphones (headphones): (i) All circuits are housed in one case (casing), and the earphones are connected to this through a cord.

(ii) A type of headphone that has all the circuits integrated into it and is worn on the head.

has been put into practical use.

However, in the receiver of type (i), there is a limit to miniaturization and thinning due to the built-in battery. Furthermore, if you operate the receiver while it is in your pocket, it may be difficult to find the position of the knobs, and you may not be able to tune in to the desired station because you cannot check the tuning position unless you take it out of your pocket. Also, with type (ii) receivers, it is not possible to select a station while looking at the dial scale, so it is not possible to confirm the received station, and the correct selection may not be possible. Furthermore, it is not easy to operate.

Purpose of the Invention This invention attempts to solve these problems.

SUMMARY OF THE INVENTION Therefore, in the present invention, the receiver is composed of a receiver main body, an operation section, and an earphone section,
This earphone section has a built-in battery, and the voltage of this battery is supplied to the receiver body as an operating voltage, and the tuning voltage is supplied from the operation section to the receiver body for tuning. be.

Embodiment That is, in FIG. 1, 1 is a receiver main body, 2 is an operating section, and 3 is an earphone section.

In the main body 1, 11 indicates a receiving circuit (tuner circuit) having from a high frequency tuning circuit to a demodulation circuit, and 11A indicates the high frequency tuning circuit;
11B is a resonant circuit of the local oscillation circuit.

These circuits 11A and 11B are connected to the coil
Variable capacitance diodes D 1 and D ₂ are connected in parallel to L _{1 and} L 2 through bypass capacitors C _{1 and} C ₂ , and buffer resistors R ₁ and R ₂ are connected to diodes D 1 and D _{2 .} A tuning voltage Ec is supplied. In this way, the target broadcast is selected by the channel selection voltage Ec, and the audio signal from the broadcast is extracted from the receiving circuit 11.

In addition, 12 is a low frequency amplifier, 13 is a 3-terminal earphone jack, and R ₃ is a variable resistor for main volume adjustment. ₃ is connected, and the output terminal of the amplifier 12 is connected to the hot side output terminal _13B of the jack 13 through a DC cut capacitor C3.

Furthermore, terminal 13B of jack 13 and circuit 1
A resistor _R4 having a predetermined value for separating the audio signal and the DC voltage (operating voltage) is connected between the hot side power supply lines 18 of No. 1 and 12, and
The ground side output terminal 13C of the jack 13 is connected to the ground side power supply line 19 of the circuits 11 and 12, and a decoupling capacitor _C4 is connected between the lines 18 and 19. In addition, resistors R ₁ and R ₂ are connected to the output terminal 1 of the jack 13.
Connected to 3A.

Note that the above circuits and elements are housed integrally in one case 10 as shown by the chain line.

In addition, in the operation unit 2, 21 is a three-terminal earphone plug, 22A to 22C, 23A to 23C.
is a 3-core earphone cord, 24 is a constant voltage circuit,
_R5 is a variable resistor for channel selection, and _R6 is an auxiliary variable resistor for volume adjustment.

Then, the hot side terminal 21B of the plug 21 is
It is connected to the input end of the constant voltage circuit 24 through the cord 22B and further through the variable resistor _R6 , and the ground side terminal 21C of the plug 21 is connected to the ground side power line 29 of the constant voltage circuit 24 through the cord 22C. In addition, the constant voltage circuit 24
Between the output terminal of and the line 29, a variable resistor R ₅
is connected, and the movable element is connected to the cord 22A.
The terminal 21A of the plug 21 is connected through the terminal 21A of the plug 21.

In addition, the above constant voltage circuit 24 and variable resistor
R ₅ and R ₆ are for one case 20 as shown by the chain line.
Although not shown, the case 20 is provided with, for example, a clip.
This allows the operating unit 2 to be kept in a chest pocket or the like.

Further, in the earphone section 3, numeral 31 indicates an earphone unit (earphone body) that converts an audio signal into reproduced sound, and this is of a dynamic type (magnetic type) so that a direct current can flow therethrough. Furthermore, 32 indicates a battery that serves as an operating power source for this receiver, and this is a flat battery such as a G-13 type battery, a so-called button battery.In this example, this battery 32 is 2. Several button batteries are connected in series.

These units 31 and batteries 32 are connected in series, and this series circuit is connected to the earphone cord 2.
It is connected to the movable element of the variable resistor _R6 and the power supply line 29 through 3A and 23C. Furthermore, the connection point between the unit 31 and the battery 32 is connected to the input end of the constant voltage circuit 24 through the earphone cord 23B.

Further, in this case, the battery 32 is housed in a housing 30 integrally with the unit 31, and the cords 23A to 23C are drawn out from the housing 30. Therefore, earphone cords 22A to 22C and 2
The operating section 2 is provided between the terminals 3A to 23C, and the plug 21 and the earphone section 3 are provided at both ends thereof.

According to this configuration, when the plug 21 is inserted into the jack 13, the ground side power lines 19, 29 and the ground side electrode of the battery 32 are connected to each other through the terminals 13C, 21C and the cords 22C, 23C. Also, at this time, the hot side electrode of the battery 32 is connected to the cord 23B → resistor R ₆ → cord 22B → terminal 21B → terminal 13B → resistor
Since the circuits 11 and 12 are connected to the power supply line 19 through the current path R ₄ , the circuits 11 and 12 operate using the battery 32 as a power source.

Therefore, the audio signal from the receiving circuit 11 is transmitted through the variable resistor R ₃ → amplifier 12 → capacitor C ₃
→Terminal 13B → Terminal 21B → Cord 22B → Variable resistor R ₆ → Cord 23B is supplied to the unit 31 through the signal line, and at this time, since the impedance of the battery 32 is generally sufficiently low, the reproduced sound is output from the unit 31. can get.

In this case, the series circuit of resistor R ₄ and capacitor C ₄ becomes the AC load of amplifier 12.
Resistor for variable resistor R ₆ and unit 31
By keeping R ₄ at a relatively large value, resistor R ₄ and capacitor C ₄ as AC loads can be ignored.

Moreover, the resistors R ₄ and R ₆ are connected to the battery 32 and the circuit 11,
Since the circuit 11 is connected in series to the current path between the power supply line 18 of the circuit 12, a voltage drop occurs in the resistors R ₄ and R ₆ , and the operating voltage supplied to the circuits 11 and 12 becomes lower accordingly. , 12 can each be about 1 mA, and therefore, the voltage drop across the resistors R ₄ and R ₆ is also extremely small, so there is no problem. Furthermore, for the same reason, there is no problem even if a direct current flows through the unit 31.

At this time, the voltage of the battery 32 is supplied to the constant voltage circuit 24 through the cord 23B, stabilized, and then supplied to the variable resistor _R5 , and the channel selection voltage Ec is taken out from the movable element. and,
This voltage Ec is supplied to diodes D ₁ and D ₂ through cord 22A → plug 21A → jack 13A → resistors R ₁ and R ₂ . Therefore, the variable resistor R ₅
By adjusting the voltage Ec, the voltage Ec changes and tuning can be performed.

Also, if you adjust variable resistor R ₃ or R ₆ ,
You can adjust the volume.

As described above, broadcasting can be received. In this case, in particular, according to the present invention, the battery 32 is stored in the earphone part 3 and not in the main body part 1, so the size of the battery 32 can be adjusted. The size and shape of the main body part 1 are not affected by the shape, and the main body part 1
can be made smaller and thinner.

In addition, since the tuning knob is provided on the operation section 2, the user can tune the channel while looking at the dial scale even when the main body section 1 is in the pocket, thereby correctly selecting the desired station. Furthermore, it does not impair the operability of channel selection and volume.

In the example shown in FIG. 2, an amplifier 12 is provided in the earphone section 3. That is, in this example, capacitors C ₆ and C ₈ are for DC cut,
Capacitor C ₇ is for bypass, resistor R ₈ is for controlling the audio signal level together with variable resistor R ₆ , resistor R ₉ is for separating the audio signal and DC voltage as well as resistor R ₄ . Reference numerals 38 and 39 are power supply lines for the hot side and the ground side. Further, the operation 2 and the earphone section 3 are connected by two-core earphone cords 23A and 23C.

Therefore, the voltage of the battery 32 is supplied to the amplifier 12 through the line 38, and also from the resistor R ₉ to the cord 23A to the cord 22B to the terminal 21.
The signal is supplied to the receiving circuit 11 through the current path B→terminal 13B→resistor _R4 , and the circuits 11 and 12 operate.

The audio signal from the receiving circuit 11 is then supplied to the unit 31 through the signal path of capacitor C ₆ → resistor R ₈ → terminal 13B → terminal 21B → code 22B → code 23A → capacitor C ₈ → amplifier 12 → capacitor C ₃ . The reproduced sound is obtained from the unit 31.

At this time, since the capacitor C ₇ is working as a bypass, the audio signal from the receiving circuit 11 is divided by the resistors R ₈ and R ₆ and supplied to the amplifier 12. , the volume can be adjusted using the variable resistor _R6 .

Also, the battery 32 obtained through the code 23A
voltage is applied to constant voltage circuit 2 through variable resistor _R6 .
3, the tuning voltage Ec is obtained from the variable resistor _R5 , and this voltage Ec is supplied to the main unit 1 to perform tuning.In addition, in the above, the resistors _R4 , _R9 A coil or constant current circuit may be used instead.
Furthermore, when the output stage of the amplifier 12 operates in class A mode, the capacitor _C3 is not necessarily required. Further, the receiving circuit 11 may be of an electronic tuning type that can select a channel using a channel selection voltage Ec. Also,
The amplifier 12 can also be provided with a tone control circuit, a tone quality changeover switch, and the like. Furthermore, the upper limit of the voltage Ec can be increased by providing the constant voltage circuit 24 with the function of a DC-DC converter.

Effects of the Invention The shape and size of the receiver main body are not limited by the shape and size of the battery, making it possible to achieve miniaturization and thinning. In addition, you can tune in while looking at the tuning position, allowing you to tune in to the desired station correctly.

[Brief explanation of the drawing]

1 and 2 are connection diagrams of an example of the present invention. 1 is a receiver body, 2 is an operating section, 3 is an earphone section, 11 is a receiving circuit, and 32 is a battery.

Claims (1)

[Claims] 1 Consists of a receiver main unit, an operation unit, and an earphone unit, and the receiver main unit has a receiving circuit that receives broadcasts and extracts audio signals, and this receiving circuit selects a channel by a channel selection voltage. The operating section has a forming means for forming the tuning voltage, and the earphone section has an earphone unit that converts the audio signal into a reproduced sound, and the receiving circuit and A built-in battery that serves as an operating power source for the forming means is provided, and the operation section is provided between the earphone cord of the earphone section, and the voltage of the battery is supplied from the earphone section to the forming means and the receiving circuit through the earphone cord. and the tuning voltage from the forming means is supplied to the receiving circuit through the earphone cord, and the audio signal from the receiving circuit is supplied to the earphone unit through the earphone cord.