JPH0761028B2 - Synthesizer tuner - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a synthesizer tuner using a PLL (phase locked loop) as a local signal oscillator, and is particularly suitable for manual tuning and seek by a combination of a small number of operation keys. The feature is that a plurality of tuning operations such as tuning and preset channel recall tuning can be switched and used.

[Conventional technology and its problems]

2. Description of the Related Art Synthesizer tuners that use a PLL as a local signal oscillator and call out a desired reception frequency by changing the frequency division ratio data N given to a programmable divider of the PLL are widely used.

As described above, since this synthesizer tuner can select the reception frequency by changing the frequency division ratio data N given to the programmable divider, the frequency division ratio data N is increased step by step by operating the up or down key, for example. Alternatively, by decreasing the value, manual tuning can be performed.

In addition, the frequency division ratio data N is automatically increased or decreased step by step, and the received electric field strength is detected.
It is also possible to stop the change of the frequency division ratio data N when the received electric field strength is equal to or higher than a predetermined value, and perform seek tuning so that the received frequency is received.

Furthermore, it is possible to receive relatively well in the area.
It is also possible to preset about 6 broadcast reception frequencies, and perform preset recall tuning in which the preset number of preset recall keys are pushed to directly recall preset reception frequencies.

In a conventional synthesizer tuner, if you try to configure so that you can select multiple types of tuning methods as described above, you need an up / down key to perform manual tuning and seek tuning, and preset channel recall tuning. It is necessary to have about 5 to 6 preset recall keys for performing the operations.

For example, in an in-vehicle tuner, these various keys are operated while the vehicle is being driven, and when trying to operate the keys by groping, satisfactory operation may not be obtained, and there is a hindrance to safe driving. May occur.

[Object of the Invention]

Therefore, an object of the present invention is to solve the above-mentioned conventional problems, and it is possible to easily switch and select a plurality of tuning means described above by a combination of a small number of keys and to perform tuning in each mode. An object of the present invention is to provide a synthesizer tuner that is easy to operate and has a reduced number of necessary operation keys to improve operability.

[Outline of Invention]

In order to achieve the above-mentioned object, in a tuner made according to the present invention, manual tuning for operating the up and down control keys to sequentially increase or decrease the frequency division ratio data N by one step, and its operation. Seek tuning, in which the frequency division ratio data N is automatically increased or decreased sequentially and the change of the frequency division ratio data N is stopped and the reception frequency is received when the received electric field strength is above a predetermined level. It is characterized in that the frequency division ratio data N corresponding to a plurality of broadcast reception frequencies preset by the operation are used for the preset recall tuning operation.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention. That is, 1 indicates a receiving antenna and RF from this antenna 1
The signal is amplified by the RF amplifier circuit 2 and applied to the mixer 3. A local signal obtained from a local signal oscillator 4 is applied to this mixer 3.

The local signal oscillator 4 is composed of a PLL. That is, 41 is a reference signal oscillator using a crystal or the like, and the output of this oscillator 41 is applied to one input end of the phase comparator 42.

On the other hand, the output from the programmable frequency divider 43 is applied to the other input terminal of the phase comparator 42,
42 compares the phases of these two outputs and produces a DC output based on their phase difference.

The DC output from the phase comparator 42 is applied to a low pass filter (hereinafter referred to as LPF) 45 via a charge pump 44, and the DC output obtained by this LPF 45 is a voltage controlled oscillator (hereinafter referred to as VCO). Applied to 46. The VCO 46 applies an oscillation output based on the DC output VT from the LPF 45 to the mixer 3 and a prescaler 47.

The output of the VCO 46 divided by the prescaler 47 is applied to the programmable frequency divider 43 to form a PLL loop.

The IF signal obtained by the mixer 3 is amplified by the IF amplification circuit 5 and then FM-detected by the FM detection circuit 6. The demodulated output FM-detected by the FM detection circuit 6 is applied to an MPX (stereo multiplex) circuit 7, and after being separated into right and left, a voice signal is output to output terminals Lout and Rout.

On the other hand, the programmable frequency divider 43 of the PLL 4 is adapted to be supplied with the frequency dividing rate data N of the frequency divider 43 from the control circuit 8 composed of a microprocessor. Detect the IF level in 5,
The output of the station detection circuit 9 that generates an output when the level is equal to or higher than a predetermined level is applied.

A keyboard 10 is connected to the control circuit 8, and tuning and memory operations are performed by the keyboard 10.

That is, the keyboard 10 is provided with the up and down control keys 101, and each time the control key 101 is operated by one step, the frequency division ratio data is controlled to be up or down by one step. As a result, the tuner is manually selected. It can be performed.

When any one of the up and down keys is pushed for a predetermined time or more, the frequency division ratio data N is automatically increased or decreased sequentially. At this time, the station detection circuit 9
When the output is obtained from, the seek tuning is performed so that the change of the frequency division ratio data N is stopped and the reception frequency is received.

The frequency division ratio data N corresponding to the tuned broadcast frequency can be preset in one of the station keys 103 by operating the memory key 102 and the station key 103. By operating again, it is possible to perform preset recall tuning in which the frequency division ratio data N corresponding to a plurality of preset broadcast reception frequencies are sequentially called.

The reception frequency tuned by these tuning operations is displayed by the display 11 connected to the control circuit 8.

On the other hand, the control circuit 8 includes a remote control device 12
Is also applied.

The remote control device 12 is provided with an up and down control key 121, and the manual tuning mode, the seek tuning mode, and the preset station recall tuning mode are cyclically switched by pushing the up and down two keys at the same time. Is done as

By operating one of the up and down keys in each tuning mode, the tuning operation in each mode is performed.

That is, one end of each up / down control key 121 is connected to the + B power source, and the other end is connected to each input end of the AND circuit 122.

The output terminal of the AND circuit 122 is connected to the ternary ring counter 123, and therefore the output terminals Mu, Se, P of the ring counter 123 are connected.
For r, the counter 123 is operated only when the UP U and DOWN D keys are operated at the same time, and the levels of the respective output terminals sequentially become high levels, and the manual tuning mode Mu, seek tuning mode Se, preset station recall are sequentially performed. A command is applied to the remote controller control circuit 123 to switch to the tuning mode Pr.

The other ends of the up U and down D keys are connected to the other ends of the exclusive OR circuits 124 and 125, respectively. Therefore, when one of the up U and down D keys is operated, the exclusive OR circuits 124 and 125 One input terminal has a high level and the other input terminals of the exclusive OR circuits 124 and 125 have a low level, so that the up signal or the down signal is applied to the remote control circuit 126. At this time, due to the action of the exclusive OR circuits 124 and 125, even if both up / down keys U and D are pushed at the same time, the ring counter 123 only operates and the remote controller control circuit 126 goes up and down. No signal is applied.

Remote control circuit that received up signal or down signal
In the manual tuning mode Mu, the 126 is
Every time the up / down key 121 is operated by one step, the control circuit 8 on the tuner main body side is driven so as to control the frequency division ratio data by one step up or down, and as a result, the tuner can perform manual tuning.

Also, in seek tuning mode Se,
Each time the down key 121 is operated, the frequency division ratio data N is automatically and sequentially increased or decreased. At this time,
When an output is obtained from the station detection circuit 9, the frequency division ratio data N
Then, the control circuit 8 on the tuner main body side is driven so as to stop the change of the signal and receive the reception frequency.

Further, in the preset recall tuning mode Pr, every time the up / down key 121 is operated, the control circuit 8 on the tuner body side is driven so as to sequentially call the frequency division ratio data N corresponding to a plurality of preset broadcast reception frequencies.

FIG. 2 shows a second embodiment of the present invention,
Only the remote control operation part is shown.

In FIG. 2, the same parts as those in FIG. 1 are designated by the same reference numerals, and therefore, the description of the same parts as those in FIG. 1 will be omitted.

In this device, a tuning mode changeover switch 127 is connected between the power source + B and the ring counter 123, so that each time the switch 127 is pushed, the tuning mode can be changed over in sequence.

In this embodiment, the remote control device basically requires three keys.

In the above description, the remote control device 12 is provided with a function of switching between the three tuning modes, and the up / down keys are used to perform the tuning operation in each tuning mode. Of course, it may be provided on the side.

Further, the key operation by the key matrix may be fetched in timing by the CPU operation of the remote controller control circuit 126, and the up / down / ternary counter may be detected by the CPU by inputting the up / down key.

[Effect]

As is clear from the above description, according to the present invention, it is possible to select a plurality of tuning modes by a combination of a few keys, and the tuning operation is performed by the up / down keys in each tuning mode, and necessary operation is performed. Since the number of keys can be reduced, it is extremely easy to operate.

Therefore, for example, when it is used for a vehicle-mounted tuner, it is preferable for safe driving.

[Brief description of drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention, and FIG. 2 is a block diagram showing a second embodiment of the present invention. 1 ... Antenna, 2 ... RF amplifier circuit, 3 ... Mixer,
4 ... Local signal oscillator (PLL), 5 ... IF amplification circuit, 6 ... FM detection circuit, 7 ... MPX circuit, 8 ... Control circuit, 9 ... Station detection circuit, 10 ... Keyboard, 11 ... … Display, 12 …… Remote control device.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koichi Miyano 25 Nishi Nishimachi, Kawada City, Saitama Prefecture 1 1 Nishikawa, Pioneer Co., Ltd. Kawagoe Factory (72) Isao Matsumoto 1 25 Nishimachi Nishi Yamada, Kawagoe City, Saitama Prefecture Pioneer Co., Ltd. Kawagoe Factory (56) References: 1-122628 (JP, U) 1-162934 (JP, U) 1-162934 (JP, U) 55-33560 (JP, U)

Claims (1)

[Claims] 1. A manual tuning mode in which a constant frequency is increased or decreased every time the up control key or the down control key is pressed, and a received electric field strength is a predetermined value or more by continuously increasing or decreasing the frequency. In the synthesizer tuner of the receiving device, which has a seek tuning mode for stopping when a read operation is performed and a preset tuning mode for oscillating a frequency corresponding to the read value by reading or reading up or down a plurality of preset recorded values, The manual tuning mode, the seek tuning mode, or the press tuning detecting means for detecting that both the key and the down control key are pressed, and the manual tuning mode, seek tuning mode or Preset Chu Synthesizer tuner characterized by comprising a mode selection means for selecting a ring mode, a.