JPH084752Y2 - Telephony mode receive tuning display - Google Patents

Description

[Detailed description of the device]

[0001]

[Industrial application] Telegraph (CW) in wireless communication equipment
The present invention relates to a reception tuning display during communication.

[0002]

2. Description of the Related Art In a radio communication device, the same frequency communication in which the transmission frequency and the reception frequency are completely matched is normally performed. However, in the case of telegraph (CW) communication, the transmission side carrier signal of the transmitting side is the local station. It is extremely difficult to match the transmission carrier signals of the above. Therefore, first, the frequency of the received signal from the partner station is accurately matched by the receiver and received. In the next step, the transmission frequency is made to match the received frequency, but since the received frequency alone does not produce sound, beat detection is performed using a signal with a certain frequency difference. Since matching the transmission / reception frequencies causes a difference in frequency for beat detection, various circuits have been proposed as a matching method, but in the case of the present invention, the field of matching the transmission frequencies is not included. Only the reception tuning part will be described.

Since no audible sound can be obtained even when the frequency of the telegraph signal is received and detected, a BFO signal having a frequency difference of about 800 Hz with respect to the frequency of the received telegraph signal is supplied to the mixer to obtain the difference frequency. Get the beat signal of. This is amplified and sounded by the speaker. The BFO oscillator that outputs the BFO signal has a function that allows the oscillation frequency to be slightly changed to produce a desired sound. Actually, even if the oscillation frequency is set so that the BFO oscillator has a desired beat sound, if the reception frequency of the telegraph signal is out of synchronization, the desired sound will not be obtained and the tone will be different. Therefore, there is also used a method in which a reception tuning indicator capable of displaying the reception frequency of the telegraph signal in the frequency order of low-frequency sounds obtained by beat detection is used to accurately tune the telegraph signal.

FIG. 4 is a block diagram of a reception tuning indicator for a telegraph signal. The figure will be described. The frequency of the received telegraph signal is input to the mixer 7 through the RF amplification and intermediate frequency circuit. The BFO output from the BFO oscillator 8 is input to the mixer 7 as a local signal, and the telegraph signal received and converted into the intermediate frequency is subjected to beat detection to cause the speaker to sound. A part of this beat detection signal is branched so as to be a display signal and is input to the frequency-voltage conversion circuit 2. Here, the signal converted into the DC voltage is input to the window comparator 3, and is output from the corresponding decoder output terminal of the window comparator 3 by the voltage converted according to the frequency. The decoder terminals of the window comparator 3 are connected to a reception tuning display in which the same number of light emitting elements are arranged.

In the above-mentioned circuit, the display at the center of the display 4, that is, the display point when the received frequency matches the set frequency, depends on the timbre of the frequencies detected by beat detection of the signal of this position display. When the frequency is converted to, for example, 600 Hz, the frequency-voltage conversion circuit 2 sets the frequency-converted voltage to a voltage that can be output to the center in the decoder output terminal order of the window comparator 3.

[0006] Actually, in the case where the beat-detected signal of the telegraph signal becomes the decoded signal after the frequency / voltage conversion, the BF is selected according to the operator's preference when the display 4 emits light.
The tuning display point of the display 4 changes depending on two factors, that is, the frequency selected by the O oscillator 8 and the tuning accuracy of the reception frequency at which the telegraph signal is received.
If the oscillation frequency adjustment of the oscillator 8 and the center point setting voltage of the integrating circuit 2 are configured to interlock with each other, the center of the display 4 lights up when the frequency of the telegraph signal is accurately tuned. When the display is turned on outside the center of the display 4, the frequency is shifted upward or downward.

[0007]

In the above-mentioned display method, even if a telegraph signal is not received, due to noise or the like, light-emission display or blinking light-emission display is generated at the portion displaying the reception tuning point. Is. For this reason, when the actual telegraph signal is received, it is often difficult to see the lighting display received and the light emission or blinking light emission display due to noise or the like. In order to improve this problem, the purpose is to display only the mark signal of the received telegraph signal.

[0008]

[Means for Solving the Problem] Is the reception frequency at the receiver?
PLL circuit and frequency voltage conversion of the demodulation frequency obtained from
Converted to DC voltage in the circuit and forwarded in the window comparator
Means for controlling a plurality of light emitting elements using direct current voltage
And controlling the light emitting element in the locked state of the PLL circuit
And the reception frequency only when the telegraph signal is a mark signal.
The telephony mode reception is characterized by displaying the tuning status of
A signal tuning display device is provided.

[0009]

The beat output signal, which is received by receiving the telegraph signal and is subjected to the beat detection, outputs the beat sound from the speaker through the low frequency amplifier, and at the same time, a part of the beat output signal is output only in the frequency range of 400 Hz to 800 Hz by passing through the PLL circuit. To do. This output is converted into a DC voltage by the frequency-voltage conversion circuit, input to the window comparator, and output to the light-emitting element of the display connected to the decoder terminal whose output terminal is different due to the voltage difference. Is input to the display as a display control signal, the display is off while the unlock signal is present, and the display emits light when the PLL circuit is locked. Therefore, the noise and space signals of the telegraph signal are not displayed.

[0010]

1 is a block diagram of a reception tuning display device in a telegraph communication mode according to an embodiment of the present invention. 1 will be described. Reference numeral 1 is a PLL circuit, and 2 is a frequency voltage conversion circuit. Reference numeral 3 is a window comparator, and 4 is a display. The receiving circuit is beat-detected by the local signal of the BFO oscillator 8 in the mixer 7 from the antenna through the high frequency circuit 5 and the intermediate frequency circuit 6. This beat detection signal is the P
LL1 and low-frequency amplifier 9 are branched and one is for display,
The other sounds from the speaker as a beat sound.

Next, the reception tuning display device will be described. The PLL circuit 1 which inputs the beat detection signal is 400 Hz to 8 Hz.
Since the signal is locked at the frequency of 00 Hz band, signals within this range are output. This output is converted by the frequency-voltage conversion circuit 2 into a voltage proportional to the level of the input frequency. At this time, the voltage converted between the window comparator 3 in the next stage is BF as described in the prior art.
The frequency difference between the O oscillator 8 and the received signal is set to the best, and the voltage converted by the beat detection signal frequency when the frequency of the received telegraph signal matches the set frequency is the decoder output of the window comparator 3. The reference value of the frequency-voltage conversion circuit is set to be the center of the terminal group and the center of the light emitting display element group of the display unit 4. Further, the display 4 is provided with a light emitting display element so as to display the best point of the beat detection signal, that is, the center of the display, and within the range of ± 100 Hz around the frequency at which the central display element 4a emits light in the figure. It is an indicator 4 having a structure.

In addition to the above circuits, the unlock signal of the PLL circuit 1 is supplied as a display control signal of the display 4. This unlock signal is locked when a frequency between 400 Hz and 800 Hz is input, the unlock signal changes to a lock signal, and the display 4 is illuminated and displayed only during this lock period. That is, the display 4 is displayed only during the mark signal period of the mark and space signals of the telegraph signal, and blinking display is performed by the mark and space of the telegraph signal. The central display element 4a of the display unit 4 has a shape different from that of other display elements or is marked so that it can be distinguished from other portions.

FIG. 2 shows a reception tuning display 4 provided on a part of a frequency display liquid crystal panel on the front panel of a wireless communication device.

FIGS. 3a and 3b show indicators having different structures.

[0015]

The reception tuning display device for displaying a telegraph signal using the beat detection signal according to the present invention branches the beat detection output from the PLL circuit to the frequency voltage conversion circuit and the window comparator, and a plurality of output terminals thereof. Since the unlock signal is supplied from the PLL circuit and the circuit that supplies the display device to which the display element is connected, respectively, the display signal is displayed only when the mark signal of the telegraph signal is displayed. It is eliminated, and even if a narrow band filter is used, the frequency can be adjusted accurately, so that the practical effect is great.

[Brief description of drawings]

FIG. 1 is a block diagram of a reception tuning display device in a telegraph communication mode according to an embodiment of the present invention.

FIG. 2 is an external view in which a liquid crystal panel for frequency display on a front panel of a wireless communication device is provided with a reception tuning indicator in a telegraph communication mode.

FIG. 3a is a view showing a shape of a display in which a plurality of light emitting display elements are linearly arranged. FIG. 3b is a diagram showing the shape of a display in which a plurality of light emitting display elements are arranged in an arc shape.

FIG. 4 is a block diagram of a conventional reception tuning display circuit for receiving a telegraph signal.

[Explanation of symbols]

 1 PLL circuit 2 Frequency voltage conversion circuit 3 Window comparator 4 Display 4a Center display point 5 High frequency circuit 6 Intermediate frequency circuit 7 Mixer 8 BFO oscillator 9 Low frequency amplifier 10 Speaker

Claims (1)

[Scope of utility model registration request] 1. A demodulation frequency obtained from a reception frequency at a receiver.
Converts the wave number into a DC voltage with a PLL circuit and frequency voltage conversion circuit
Convert and use the DC voltage in the window comparator
Means for controlling a plurality of light emitting elements, and the PLL circuit
With the means for controlling the light emitting element in the locked state of the road,
Displays the tuning status of the received frequency only when the mark signal of the signal is received
A reception tuning display device in a telegraph mode characterized by: