JPH0612865B2 - Synthesizer receiver - Google Patents

Description

The present invention relates to a synthesizer type receiver.

[Conventional technology]

Manual tuning and scan tuning are available as channel selection methods for synthesizer-type receivers.

In other words, manual tuning, when you press the manual tuning up key (or down key),
While this button is being pressed, the reception frequency rises (or decreases) step by step. If you stop pressing the button at any point, the change in the reception frequency will stop, and thereafter, reception will continue at the reception frequency at the time of the stop. It is a thing.

Further, in scan tuning, the reception frequency is continuously increased (or decreased) by one step only by temporarily pressing the scan tuning up key (or down key). Scanning stops at the frequency, and the signal continues to be received thereafter.

Therefore, by using this manual tuning and scan tuning together, tuning can be performed easily regardless of the known frequency or unknown frequency, and it is very convenient to use for reception of short-wave band and aviation radio. is there.

[Problems to be solved by the invention]

If both manual tuning and scan tuning can be performed with one receiver, an up key and down key for manual tuning, and an up key and down key for scan tuning are required, and four keys are required on the operation panel. A tuning key must be provided. However, in a small receiver such as a portable receiver, it is not preferable to provide four tuning keys because the operation panel is narrow.

[Means for solving problems]

A detection circuit (21) for detecting the reception level of the reception signal, a level setting means (23), and a comparison circuit for comparing the setting signal from the level setting means (23) with the detection signal from the detection circuit (21). (22), the up key (43) and the down key (44), the comparison signal of the comparison circuit (22) and the up key (4)
3) and a control circuit (30) that raises or lowers the reception frequency at a predetermined frequency based on the output of the down key (44) and presses the up key (43) or the down key (44) In this case, the reception frequency is increased or decreased by one step, and at this time, the detection signal is larger than the setting signal based on the comparison signal, and the up key (4
3) Or when the down key (44) is pressed and the detection signal is smaller than the setting signal, the reception frequency continues to increase or decrease, the detection signal is larger than the setting signal, and the up key (43) Alternatively, when the down key (44) is not pressed, the rising or falling of the reception frequency is stopped.

[Action]

When the up key (43) or the down key (44) is pressed, the reception frequency increases or decreases by one step, and the detection signal is larger than the setting signal based on the comparison signal at this time, and the up key When the (43) or down key (44) is pressed and the detection signal is smaller than the setting signal, the reception frequency continues to rise or fall, the detection signal is larger than the setting signal, and the up key When the (43) or down key (44) is not pressed, the rise or fall of the reception frequency is stopped.

〔Example〕

In FIG. 1, (10) shows a receiving system, and an antenna (1
The received signal from 1) is supplied to the mixer circuit (13) through the pre-recessor (12), and a local oscillation signal of a predetermined frequency is formed in the PLL (14) and supplied to this signal mixer circuit (13). Then, only the signal of the frequency desired to be received is converted into the intermediate frequency signal. Then, the intermediate frequency signal is supplied to the demodulation circuit (16) through the intermediate frequency amplifier (15) to demodulate the audio signal, and the signal is passed through the squelch circuit (squelch gate circuit) (17),
Further, it is supplied to the speaker (19) through the low frequency amplifier (18).

Further, the intermediate frequency signal from the intermediate frequency amplifier (15) is supplied to the detection circuit (21) to be a DC signal SGNL having a level corresponding to the reception level, and this signal SGNL is supplied to the voltage comparison circuit (2
2), the setting signal SQ for setting the squelch level is supplied from the variable resistor (23) to the comparison circuit (22), and the comparison output COMP is supplied to the microcomputer (30).

This microcomputer (30) constitutes a control circuit for tuning, etc. In the microcomputer (30), (31) is a 4-bit CPU, (32) is a ROM, and this ROM (32) is a tuning channel. With the program written for etc.,
The routine (60) of the flowchart shown in FIG. 2 is written. Furthermore, in the microcomputer (30), (33)
Is a work area RAM, (34) is an output port, (3
5) is an input port. And this microcomputer (30)
A ten key (41), an enter key (42), an up key (43), a down key (44), and an LCD (50) are connected to the. The keys (41) to (44) are non-lock type push switches. Also, LCD (50)
Is for displaying the frequency and the like.

Further, data of a predetermined frequency division ratio is taken out from the microcomputer (30) and supplied to a variable frequency division circuit (not shown) of the PLL (14). Therefore, the local oscillation signal from the PLL (14) is transmitted. The frequency is the local oscillation frequency corresponding to the frequency desired to be received as described above. Further, in the microcomputer (30), a squelch control signal CTRL is formed based on the comparison output COMP of the comparison circuit (22), and this is supplied to the squelch circuit (17) as its control signal. When SGNL <SQ, the squelch ( Prevent sound from being emitted from the speaker (19))
Is done.

Then, for example, press the numeric keypad (41) in order of the key "1",
Press "2", "3", "4" and then press the Enter key (4
When 2) is pressed, the frequency division ratio data Ni for receiving the frequency 1234 kHz is formed, and this data Ni is stored in the RAM (33).
It is stored in BUFR address and loaded into the variable frequency divider of PLL (14).
Will be in the receiving state.

At this time, if the reception level is high and SGNL> SQ, a predetermined control signal CTRL is generated based on the comparison output COMP of the comparison circuit (22), and this signal CTRL turns off the squelch circuit (17). Squelch is released). If the reception level is low and SGNL ≦ SQ, the squelch circuit (17) is turned on (squelch operation) by the signal CTRL.

The manual tuning and the scan tuning are performed by the microcomputer (30) processing the routine (60). Note that in this example the key (43)
Or if you continue pressing (44) for 0.5 seconds or longer,
Manual tuning or scan tuning is performed, but when it is less than 0.5 seconds, it is fine tuning, that is, the reception frequency is increased or decreased by one step (9 kHz for medium-wave broadcasting).

That is, this routine (60) is a subroutine which is periodically called from a main routine (not shown) at a short cycle, and when called, starts from step (61). Then, in step (62), it is checked whether the key (43) or (44) is pressed, and if neither is pressed, the process proceeds to step (88) to reset the key flag KFLG. Then, this routine (60) is ended by the step (89).

However, when either the key (43) or (44) is pressed, the process proceeds from step (62) to step (63) to set the flag KFLG, and then at step (64) by the signal CTRL. Turn on the squelch operation of the squelch circuit (17), and then check in step (65) whether the key pressed is the up key (43) or the down key (44), and then press the up key (43). If so, in step (66), the data of the division ratio of the value for increasing the reception frequency by one step from the current frequency is formed, and P is formed.
Load the LL (14), and if the down key (44), set the reception frequency to 1 from the current frequency in step (67).
The data of the division ratio of the value to be lowered by the step is formed and loaded into the PLL (14). Therefore, the reception frequency is increased or decreased by one step by steps (66) or (67). When the reception frequency changes to the upper limit or the lower limit, it is set to the lower limit or the upper limit frequency and rises or falls again.

Then, the process proceeds from step (66) or (67) to step (68), and in this step (68), when the reception frequency is changed by the manual tuning and the scan tuning, it corresponds to the speed, that is, each frequency. The timer operation (delay) corresponding to the period when the scan is stopped is performed.

Then, the process proceeds to step (71) to check the signal COMP, and when SGNL <SQ, the process directly proceeds to step (73), and when SGNL ≧ SQ, the process proceeds to step (7).
Proceed to 2), turn off the squelch operation of the squelch circuit (17) by the signal CTRL, and proceed to step (73). Therefore, when SGNL ≧ SQ, that is, when the received signal level is high, the sound of the received signal is obtained from the speaker (19) in step (72).

Then, the process further proceeds to step (73) to set the flag KF.
If LG is checked and the flag KFLG is set, the timer operation (delay) of 0.5 second is performed in step (74), and then the process proceeds to step (81). When the flag KFLG is reset, the direct step ( Continue to 81).

Then check the signal COMP in step (81),
If SGNL ≧ SQ, the process proceeds to step (82) to check whether the key (43) or (44) is pressed. If so, reset the flag KFLG in step (83). Return to step (64), and if not pressed, flag KF in step (88).
After resetting LG, step (89) terminates this routine (60). In step (81), SG
When NL <SQ, the flag KFLG is reset in step (83) and then the process returns to step (64).

Therefore, when the squelch level is set low (the signal SQ is small) by the variable resistor (23), SGNL ≧ SQ, and the processing of the microcomputer (30) moves to step (82) after step (81). So, if you keep pressing the key (43) or (44), steps (64) to (81) → (82) →
The loop of (83) → (64) will be repeated,
The reception frequency is increased or decreased step by step according to the key (43) or (44) each time the loop is completed. Then, when the pressing of the keys (43) and (44) is stopped, the process proceeds from the step (82) to the step (89) through the step (88), so that the change of the reception frequency is stopped.

That is, when the squelch level is set low, the reception frequency increases or decreases by one step only while the key (43) or (44) is held down, and when the push is stopped, the reception frequency at that time To enter the receiving state. That is, in this case, manual tuning is performed.

During this manual tuning, the routine (60)
When step (73) is executed for the first time after is called, the flag KFLG is set by step (63). Therefore, when step (73) is executed for the first time, step (74) is executed subsequently. Then, the 0.5 second timer operation is performed. Therefore, if the user stops pressing the key (43) or (44) within 0.5 seconds, the process moves from step (82) to step (88) to step (89). Only the steps will change. That is, if the period during which the key (43) or (44) is pressed is less than 0.5 seconds, the reception frequency can be changed by one step. That is, fine tuning can be performed.

On the other hand, when the squelch level is set high (the signal SQ is large) by the variable resistor (23), SGNL <SQ, and the processing of the microcomputer (30) moves to step (83) after step (81). So, just press the key (43) or (44) temporarily, and steps (64) to (81) → (83) →
The loop of (64) is repeated, and the reception frequency is increased or decreased step by step according to the key (43) or (44) each time the loop is cycled.

However, at a certain reception frequency, the signal is received and SGNL
When ≧ SQ, the process proceeds from step (81) to step (82), and since the key (43) or (44) was temporarily pressed, the process further proceeds to step (88), This routine (60) is terminated at (89).

In other words, if the squelch level is set high, the reception frequency will continuously increase or decrease by one step only by temporarily pressing the key (43) or (44). It becomes the receiving state of. That is,
In this case, scan tuning has been performed.

Even during this scan tuning, step (73)
When is executed for the first time, step (74) is executed, so the period during which the key (43) or (44) is pressed is 0.
Within 5 seconds, the reception frequency increases or decreases by one step. That is, fine tuning can be performed.

Thus, according to the present invention, the two keys (43), (4
Only 4), the up-scan and down-scan of manual tuning, the up-scan and down-scan of scan tuning, and the up-and-down of fine tuning are performed.

〔The invention's effect〕

Up-scan and down-scan for manual tuning and up-scan and down-scan for scan tuning can be performed with only two keys (43) and (44), and the operability is good. Also, fine tuning can be performed.

In addition, the operation panel becomes simple.

Also, the operability of manual tuning is alive when performing scan tuning. Further, if the key (43) or (44) is held down, the frequency can be passed even when the squelch is turned off (a signal is received) during the scan tuning, and the scan tuning can be advanced.

[Brief description of drawings]

FIG. 1 is a system diagram of an example of the present invention, and FIG. 2 is a diagram for explaining it. (10) is a receiving system, (30) is a microcomputer, and (41) to (44) are operation keys.

Claims (1)

[Claims] 1. A detection circuit for detecting a reception level of a reception signal path, a setting means for adjusting and setting a squelch level, and a comparison circuit for comparing a setting signal from the setting means with a detection signal from the detection circuit. A squelch circuit provided in the reception signal path and performing a squelch operation when the comparison circuit detects that the detection signal is smaller than the setting signal; an up key and a down key; and a comparison signal of the comparison circuit. And a control circuit which raises or lowers the reception frequency in predetermined frequency steps based on the output of the up key or the down key, and when the up key or the down key is operated, the reception frequency is only one step. Based on the comparison signal at this time, the detection signal is higher than the setting signal and the up signal is increased. When working with over or Dan'uki, and when the detection signal is smaller than the set signal, to proceed with the raising or lowering of the reception frequency, the detection signal is greater than the set signal, and,
When the above Up or Down keys are not operated,
A synthesizer receiver configured to stop the rise or fall of the reception frequency.