JPS6017199B2 - Switching device for television receiver with magnetic recording and reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for switching the screen of a television receiver from a playback screen to a broadcast screen with a single operation of stopping playback in a television receiver with a magnetic recording and reproducing bag counterfeit.

Conventionally, when switching from the playback screen of a magnetic recording/reproducing device (hereinafter abbreviated as VTR) to the TV broadcast screen, a changeover switch was used to switch the input signal of the television (hereinafter abbreviated to TV) receiver between the TV broadcast signal and the signal from the VTR. (
The operation was complicated because it was necessary to separately operate three things: the TV/VTR switch (hereinafter abbreviated as "TV/VTR switch"), the tuner of the TV receiver, and the stop button of the VTR.

As a device for improving this, there is a device shown in FIGS. 1 to 3.

In FIG. 1, 1 is a circuit for detecting that the reproduction mode of the VTR has been stopped, 2 is a circuit for selecting a preset specific channel, 3 is a TV tuner, and 4 is a TV/VTR switch. V at playback stop detection circuit 1
It is detected that the reproduction mode of the TR is stopped, and a specific channel selection circuit 2 selects a specific channel of the TV tuner 3. When the TV tuner 3 is switched from the playback mode, the TV/VTR switch 4 is switched to the TV side. With the above operation, the screen of the TV receiver can be switched from the playback screen to the broadcast screen with a single operation. It is clear that similar effects can be obtained with the configurations shown in FIGS. 2 and 3. 1 to 4 in FIGS. 2 and 3 are the same as in FIG. 1. A detailed explanation of the block diagram of FIG. 1 will be given using FIG. 4.

In FIG. 4, 1 to 4 correspond to 1 to 4 in FIG.

6 is a capacitor that blocks direct current; 1 is a playback stop detection transistor that is activated when VTR playback is stopped; 2 is a channel selection transistor; 10 to 22 are electronic tuning tuners; 10 is a VTR signal 11 and 12 are TV receiver channel selection switches, 13 to 15 are input detection circuits, 16 to 18 are memory circuits, 19 and 21 are voltage setting circuits, 22 is the tuner body, 7 is a buffer circuit, 8 is a selector switch, 9 is RF
Converter shown.

Any number of pairs of channel selection switches, input detection circuits, memory circuits, and voltage setting circuits corresponding to numbers 10 to 21 may be connected.

Here, a is a broadcast reception signal, b is a VTR output signal, and c is a signal that has a voltage of, for example, 10 B when the VTR is playing, and has a ground potential at other times. With this circuit, VTR
When the VTR is tuned in the playback mode and a voltage is generated at the output of the memory 16, the buffer circuit 7 causes the changeover switch 8 to switch off to the RF converter 9 leg and supply power to the RF converter 9. , RF converter 9
operates and the VTR playback output is applied to the tuner body 22.

If you stop playing the VTR in this state, the potential of e will be 10B.
Since the voltage drops to ground potential, a current flows through the capacitor 6, and the regeneration stop detection transistor 1 becomes conductive, and the selection transistor 2 also becomes conductive. Therefore, the input detection circuit 14
An input is applied to the memory circuit 17, and a voltage for operating the voltage setting circuit 20 is generated at the output of the memory circuit 17. At the same time, the memory circuit 16 is reset because a reset pulse is applied to each memory. Therefore, the output of the buffer circuit 7 becomes 0, the changeover switch 8 is switched to the external antenna side, and the RF converter 9 also stops operating, so a broadcast signal is applied to the tuner body 22, and the voltage setting circuit 2 sets the voltage in advance. Select a channel and switch from the playback screen to the broadcast screen. In this way, the playback screen of the VTR can be switched to the broadcast screen with a single operation of operating the stop button on the VTR, improving operability.
At this time, if you are on the broadcast screen during VTR playback and stop playback, or if you have a configuration in which the VTR stops when you select a channel during VTR playback, the disadvantage is that when the VTR stops, the channel will automatically change to a specific channel. was there.

The object of the present invention is to eliminate the above-mentioned drawbacks of the prior art and to
To provide a switching device for a TV receiver with a VTR that can switch from a playback screen to a broadcast screen with a single operation of stopping playback of a TR, and does not malfunction when playback is stopped in other states.

The present invention provides an apparatus having the configuration shown in FIGS.
It is characterized by the insertion of a gate circuit that is opened by a signal that detects that the TR is being tuned.

By inserting this gate circuit, even if a playback stop operation is performed in a state other than when the VTR is playing, there will be no malfunction such as switching to a specific channel.

Furthermore, it goes without saying that if a playback stop operation is performed during playback of a VTR, the channel can be switched to a specific channel with a single operation. FIG. 5 shows an example of a block diagram of the present invention.

1 to 4 are similar to those shown in FIG.

5 indicates a gate circuit.

Gate circuit 5 turns 0 when tuning the VTR using tuner 3.
is open. When the reproduction of the VTR is stopped at this time, a pulse is generated by the reproduction stop detection circuit 1, and the gate circuit 5
The channel selection circuit 2 is operated through the channel selection circuit 2. tuner 3
A specific channel is selected, and this output allows the TV/V
The TR switch 4 is switched, and the TV receiver is switched from the playback screen to the broadcast screen. Since the gate circuit 5 is closed when the tuner 3 is receiving broadcasts,
Even if reproduction of the VTR is stopped, the channel selection circuit 2 does not operate and the station o selected by the tuner 3 does not change. Fifth
An example of the details of the diagram is shown in FIG.

In FIG. 6, circuits having the same contents as those in FIG. 4 are given the same numbers. Note that 5 indicates an AND gate. When the VTR signal output to the memory circuit 16 is received, the AND gate 5 is open, and when VTR playback is stopped, a specific channel of the tuner 3 is selected and the TV/VTR signal is output.
Switch 4 is switched to the TV side, but memory circuit 1
There is no output on 6. Since the AND gate 5 is closed (0) when receiving a broadcast signal, the selection transistor 2 does not operate. With the above operation, if you stop playing the VTR when receiving a broadcast, or if you select a channel while playing the VTR,
If the configuration is such that the TR stops, there will be no malfunction in which the channel changes even if the reproduction of the VTR is stopped. As described above, according to the present invention, the single operation of stopping VTR playback switches from the VTR playback screen to the broadcast screen, and the malfunction of selecting a channel does not occur in other situations, improving operability. .

[Brief explanation of the drawing]

Figures 1 to 3 are block diagrams showing examples of a device that switches from a VTR playback screen to a broadcast screen with a single operation in a TV receiver with a VTR, Figure 4 is a detailed circuit diagram of Figure 1, and Figure 5 is a detailed circuit diagram of Figure 1. The figure is a block diagram of a device for switching from a VTR playback screen to a broadcast screen with one operation according to the present invention, and FIG. 6 is a detailed circuit diagram of FIG. 1: Playback stop detection circuit, 2: Specific channel selection circuit,
3: TV tuner, 4: TV/VTR switch, 5: gate circuit. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1. In a television (abbreviated as TV) receiver with a magnetic recording and reproducing device (abbreviated as VTR), there is a circuit that detects that the reproduction mode of the VTR is stopped, and a detection signal from the detection circuit that enables the TV tuner to be activated in advance. Equipped with a circuit that selects a specific channel that has been set, and a switch that switches the input signal of the TV receiver from a VTR signal to a TV broadcast signal when the TV tuner is switched from playback mode, the TV receiver can be switched on with a single operation to stop VTR playback. In a device for switching the screen from a playback screen to a broadcast screen, a T is provided on the output side of the detection circuit.
A switching device characterized in that a gate circuit is inserted which opens in response to a signal detecting that a VTR is selected from a V tuner.