JPH033012Y2 - - Google Patents

Description

[Detailed explanation of the invention] This invention performs threshold setting in the threshold setting/fixed squelch setting section during each operation of calling, capturing, and recalling, and also uses an external instruction during call operation. Threshold setting and fixed squelch setting section,
The present invention relates to a personal radio that can be used by switching between an adjustable external squelch setting section.

As shown in FIG. 1, in a conventional personal radio, when a call signal is input from an input terminal 1 during a call, a changeover switch circuit 3 switches a threshold value setting resistor 4 in response to a signal from a control circuit 2. It switches to the contact 5 side and searches for an empty channel at a preset threshold setting level. When I searched for an empty channel,
The group number and empty channel data are transmitted to the other party via the transmitter 6 and antenna 7. A signal from the other party is received by the antenna 8 and is further sent to a high frequency amplification circuit 9, a mixing circuit 10, an intermediate frequency amplification circuit 11, a detection circuit 12, an amplification circuit 13, a filter circuit 14, a detection circuit 15 and a level detection circuit 16. ,
When the received signal level is above a certain level, a detection signal from the level detection circuit 16 is input to the control circuit 2.
If a match is found with the other party, the other party is also set to the corresponding empty channel. When the channel is set to an empty channel and a call operation is started, the signal from the control circuit 2 switches to the contact 18 side of the external squelch setting resistor 17, and also switches the mute circuit 19.
The audio signal passes through the audio amplification circuit 20 to the speaker 21
The communication is performed between the two terminals. Then, the external squelch setting resistor 17 is adjusted depending on the strength of the radio waves.

However, in such a conventional circuit, the contact 5 on the side of the variable resistor 4 for setting the threshold value is switched only while the level of the empty channel is being set, and the variable resistor for setting the external squelch is switched to the contact 5 on the side of the variable resistor 4 for threshold setting during other call operations It returns to the contact 18 on the resistor 17 side. That is, since the threshold setting and the external squelch level setting each have only a single function, the setting of the external squelch level during a call must always be adjusted with the knob of the variable resistor 17.

However, in the present invention, the threshold setting section can also be operated as a fixed squelch during a call by an external command, thereby further improving the function.

An embodiment of the present invention will be described below with reference to FIG.

Antenna 8, high frequency amplification circuit 9, mixing circuit 1
0, intermediate frequency amplification circuit 11, detection circuit 12, mute circuit 19, audio amplification circuit 20, speaker 2
1. The amplifier circuit 13, filter circuit 14, detection circuit 15, level detection circuit 16, transmitter 6, and antenna 7 are the same as the conventional configuration shown in FIG.

The feature of the present invention is that the threshold setting section 4a can be used as a fixed squelch setting section even during a telephone call, so that it can be switched by a command from an external switch circuit 22 connected to the control circuit 2a. The circuit 3a can be switched.
That is, the control circuit 2a is composed of a CPU 23, a memory 24, and an interface circuit 25. This interface circuit 25 is coupled to a calling operation input terminal 1, an external switch circuit 22, a schematic changeover switch circuit 3a, a transmitter 6, a level detection circuit 16, and a mute circuit 19. Further, one contact 5a of the squelch changeover switch circuit 3a is coupled to a semi-fixed resistor 4a serving as a threshold value setting and fixed squelch setting section, and the other contact 18a is coupled to a variable resistor 17a serving as an external squelch setting section. , common contact 26 is coupled to level detection circuit 16. Further, in the external switch circuit 22, one switching contact 27 for threshold setting and fixed squelch is coupled to a power terminal (+B) via a resistor 28, and a switching contact 29 for external squelch is grounded. .

In the configuration described above, when a call signal is input from input terminal 1 at the time of making a call, the same action as shown in Fig. 1 is used to first switch to contact 5a, search for an empty channel, and send data to the other party. . When the other party agrees and an empty channel is set, the communication returns to the contact 18a side and the communication state is established. Next, in a call state, when the external switch circuit 22 is switched to one of the switching contacts 27, the switching switch circuit 3a is switched to the contact 5a side, and the semi-fixed resistor 4a is switched to the contact 5a side.
Since it is connected to the level detection circuit 16, it functions as a squelch at a constant level, that is, as a fixed squelch setting section, regardless of the variable resistor 17a as the external squelch setting section. When the external switch circuit 22 is switched to the other contact 29, the changeover switch circuit 3a returns to the contact 5a side, and the variable resistor 17 is switched as before.
a is for external squelch setting.

Since the present invention is configured as described above, the threshold value setting/fixed squelch setting section sets the threshold value during call origination, capture, or re-calling operation, and then sets the threshold value during call operation. It can be operated as a fixed squelch setting section by switching from the normal adjustable external squelch setting section to the threshold setting side in response to an external instruction. In other words, the threshold setting section can be shared as a fixed squelch setting section. Therefore, the original external squelch setting section can set the squelch level over a wide range, and the fixed squelch setting section can set the squelch level to a quasi-target level, thereby improving the function of the squelch circuit.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a conventional personal radio, and FIG. 2 is a block diagram of a personal radio according to the present invention. 1... Calling signal input terminal, 2a... Control circuit,
3a... Changeover switch circuit, 4a... Threshold setting and fixed squelch setting section, 16... Level detection circuit, 17a... External squelch setting section, 19... Mute circuit, 22... External switch circuit, 23...
...CPU, 24...Memory, 25...Interface circuit, 27...Switching contact for threshold setting and fixed squelch, 29...Switching contact for external squelch.

Claims (1)

[Claims for Utility Model Registration] (1) A signal for calling, capturing or recalling is transmitted by a transmitter, and the received signal level from the other party is equal to or higher than the threshold setting level in the level detection circuit, and the mutual empty channel is used. In the personal radio device, the mute circuit is controlled by a control signal from the control circuit to enable mutual communication and the level detection circuit is returned to the squelch setting section when the level detection circuit matches. A threshold setting/fixed squelch setting section and an adjustable external squelch setting section are connected in a switchable manner by a changeover switch circuit, and an external switch circuit for switching the changeover switch circuit is connected to the control circuit. A personal radio device characterized in that the switch circuit comprises a switching contact for the threshold value setting/fixed squelch setting section and a switching contact for the external squelch setting section. (2) Utility Model Registration Scope of Claim 1, the personal radio device in which the threshold value setting and fixed squelch setting section consists of a semi-fixed resistor, and the external squelch setting section consists of a variable resistor. (3) In paragraph 1 of the claims for utility model registration, the control circuit includes a CPU, a memory, and this CPU.
A personal radio device consisting of an interface circuit for coupling with an external circuit.