GB2331650A

GB2331650A - VCR with wireless connection to tv

Info

Publication number: GB2331650A
Application number: GB9811311A
Authority: GB
Inventors: Sung-Kyu Park
Original assignee: Daewoo Electronics Co Ltd
Current assignee: WiniaDaewoo Co Ltd
Priority date: 1997-11-19
Filing date: 1998-05-26
Publication date: 1999-05-26
Also published as: KR19990019476U; GB9811311D0

Abstract

A video cassette recorder (VCR) incorporates a wireless radio frequency (RF) modulating device. In the wireless RF modulating device, video and audio signals read from a magnetic tape are modulated by using a predetermined carrier frequency for a channel to output modulated video and audio signals, wherein the channel is a channel that is not used for broadcasting. The power of the video and audio signals is amplified by a predetermined level to generate amplified video and audio signals. The amplified video and audio signals or an antenna input signal applied to an antenna input terminal of the VCR received is selected in response to an instruction of the VCR user. The selected amplified video and audio signals or antenna input signal is transmitted to one or more receiver sets.

Description

2331650 VIDEO CASSETTE RECORDER INCORPORATING THEREIN A WIRELESS RADIO

FREQUENCY MODULATING DEVICE The present invention relates to a video cassette recorder (VCR); and, more particularly, to the VCR incorporating therein a wireless radio frequency (RP) modulating device.

As is well known, antenna signal for a television (TV) receiver is routed through a VCR to the TV receiver. In general, the VCR comprises a splitter, a tuner and an intermediate frequency (IF) section. The splitter provides is parallel paths for signals to the tuner in the VCR and a tuner in the TV receiver. In the VCR tuner and the IF section, RP picture and associated sound signals are converted to baseband video and audio signals to be recorded on a magnetic tape. In this case, the TV receiver can be either on or off. - For playback, the VCR is equipped with an RP modulator that puts out video and audio signals on RP carrier frequency for a certain channel, e. g., 3 or 4. A modulator switch, which is a part of the RP modulator, is set to a channel which is not being used for broadcasting. Therefore, the TV receiver is also set to the same channel as the VCR, either 3 or 4, for the VCR playback. Also, a VCR switch on the front -1 panel of the VCR enables a user of the VCR to choose either the video and audio signals from the RF modulator or - an antenna input signal from the splitter. From the VCR switch, either one of the video and audio signals reproduced and the antenna input signal goes to an output jack of the VCR which is connected by a cable to antenna input terminals of the TV receiver.

Since, however, the prior art VCR so constructed transmits either the video and audio signals reproduced or the antenna input signal to the TV receiver through the cable, there exists the limitation of a distance between the VCR and the TV receiver. Further, in case the VCR is to be associated with one or more TV receivers, it becomes messy and complicated to connect cables therebetween; and there may occur a signal interference problem due to the complicated cable connections.

It is, therefore, a primary object of the present invention to provide a VCR incorporating therein a wireless RF modulating device for transmitting from the VCR either video and audio signals reproduced or an antenna input signal to one or more receiver sets by radio.

In accordance with one aspect of the invention, there is provided a video cassette recorder (VCR) incorporating therein a wireless radio frequency (RF) modulating device, the wireless RF modulating device comprising:

an RF modulator for modulating video and audio signals read from a magnetic tape by using a predetermined carrier frequency for a channel to output modulated video and audio signals, wherein the channel is a channel that is not being used for broadcasting; power amplifying means for amplifying the power of the video and audio signals to a predetermined level to generate amplified video and audio signals; means for selecting either the amplified video and audio signals or an antenna input signal applied to an antenna input terminal of the VCR in response to an instruction of the VCR user, and antenna for transmitting either the amplified video and is audio signals or antenna input signal, whichever selected, to one or more receiver sets.

In accordance with another aspect of the invention, there is provided a receiving system comprising a video cassette recorder (VCR) and one or more receiver sets, the VCR incorporating therein a wireless radio frequency (RF) modulating device, wherein the wireless RF modulating device includes:

an RF modulator for modulating video and audio signals read from a magnetic tape by using a predetermined carrier frequency for a channel to output modulated video and audio signals, wherein the channel is a channel that is not being used for broadcasting; power amplifying means for amplifying the power of the video and audio signals to a predetermined level to generate amplified video and audio signals; means for selecting either the amplified video and audio signals or an antenna input signal applied to an antenna input terminal of the VCR in response to an instruction of the VCR user; and antenna for transmitting either the amplified video and audio signals or antenna input signal, whichever selected, to one or more receiver sets; and wherein each of said one or more receiver sets includes:

receiving antenna for receiving either the amplified video and audio signals or antenna input signal transmitted through the sending antenna; and means for demodulating either the video and audio signals or antenna input signal, whichever received, to display a demodulated video signal on a monitor of each of said one or more receiver sets and sound the demodulated audio signal through a speaker thereof.

The above and other objects and features of the present invention will become apparent from the following description of preferred embodiments given in conjunction with the accompanying drawings, in which:

Figs. 1A and 1B show block diagrams of a VCR incorporating therein a wireless RP modulating device and a TV receiver associated with the VCR in accordance with the present invention, respectively.

Referring to Figs. 1A and IB, there is shown a schematic block diagram of a receiving system 100 having a VCR 200 and a TV receiver 300 in accordance with the invention. Fig. 1A illustrates a block diagram of the VCR 200 incorporating therein a wireless RP modulating device 260 and Fig. IB is presents a schematic block diagram of the TV receiver 300. As will be described below, the wireless RP modulating device 260 of the present invention is used to transmit from the VCR 200 either audio and video signals reproduced or an antenna input signal to a TV receiver 300 by radio. Although Fig. 1A illustratively shows only one TV receiver 300 for -he sake of simplicity, it should be noted that there can be provided a plurality of TV receivers for receiving the audio and video signals or the antenna input signal transmitted from the VCR 200. The VCR 200 comprises a splitter 210, a very high frequency (VHF) tuner 230, a recording/playback device 250 and the wireless RP modulating device 260. The wireless RP modulating device 260 of the present invention includes an RP modulator 262, a power amplifier 264, a VCR switch 266 and a sending antenna 268. For the purpose of simplicity, only a VHF signal path is illustratively shown in Fig. 1A, but duplicate signal paths are provided for ultra high frequency (UHF) channels.

As shown in Fig. 1A, a VHF channel is connected to a VHF input jack of the VCR 200. Conventionally, a balun is used to convert a 300-0 twin-lead cable to 750 coaxial jack. The VHF channel connected to the VHF input jack is then applied to the splitter 210. The splitter 210 provides parallel paths for signals travelling to the VHF tuner 230 and the VCR switch 266 for transmission thereof to a VHF tuner (not shown) in an audio/video signal demodulating device 330 of the TV receiver 300.

For recording, the VHF tuner 230 and an IF section (not shown) supply baseband video and audio signals to be recorded on a magnetic tape (not shown) prepared in the recording/playback device 250.

audio signals recorded on the magnetic tape are read therefrom; and are transferred to the RF modulator 262. The RF modulator 262 modulates the video and audio signals by using a predetermined carrier frequency for a certain channel. In other words, the RF modulator 262 supplies RF picture and sound carrier signals for the TV receiver 300 on a channel, e.g., 3 or 4, and provides them to the power amplifier 264. as modulated video and audio signals. A modulator switch (not shown), which is part of the RF modulator 262, can be set for either one of the two channels- On playback, the video and The power amplifier 264, equipped with a high power output amplifier, amplifies the power of the modulated video and audio signals from the RF modulator 262 to a predetermined level. As can be inferred from the above, the purpose of such a power amplifying is to transmit the signals from the RF modulator 262 to the TV receiver 300 through the sending antenna 268 without forming any cable between the VCR 200 and the TV receiver 300. Since power amplifying scheme is widely used in, e.g., a conventional broadcast transmitting system, more details thereof are omitted here for the sake of simplicity.

is The amplified video and audio signals are provided from the power amplifier 264 to the VCR switch 266. In Fig. 1A, the VCR switch 266, located on the front panel of the VCR 100, is also set to the VCR position for playback. The VCR switch 266 enables one to choose either the amplified sictnals from the power amplifier 264 or the antenna input signal from the splitter 210; and then a chosen signal, either the amplified signals or antenna input signal, is transmitted to the TV receiver 300 through the sending antenna 268.

Turning now to Fig. 1B, there is shown a schematic block diagram of the TV receiver 300 associated with the VCR 200 in accordance with the invention. The TV receiver 300 includes a receiving antenna 310, an audio/video signal demodulating device 330, a monitor 350 and a speaker 360. Either one of the amplified signals and the antenna input signal transmitted through the sending antenna 266 is received first by the receiving antenna 310. And then, either the amplified signals or the antenna input signal that is received by the receiving antenna 310 is processed to demodulate at the audio/video signal demodulating device 330 having a tuner, an IF amplifier and an audio/video detection circuit. Details of the audio/video signal demodulating device 330 are omitted here for the purpose of simplicity as it is well known in the art. Thereafter, the audio and video signals demodulated at the audio/video signal demodulating device 330 are sounded through the speaker 360 and displayed on the monitor 350, respectively. As shown above, therefore, the present invention is capable of transmitting from the VCR either the amplified signals or the antenna input signal to one or more is receiver sets by radio by employing the novel wireless RF modulating device.

while the present invention has been shown and described with respect to the particular embodiment, it will be apparent to those skilled in the art that many changes and modifications may be made without departing from the scope of the invention as defined in the appended claims.

Claims

Claims:

1. A video cassette recorder (VCR) incorporating therein a wireless radio frequency (RF) modulating device, the wireless RF modulating device comprising:

an RF modulator for modulating video and audio signals read from a magnetic tape by using a predetermined carrier frequency for a channel to output modulated video and audio signals, wherein the channel is a channel that is not being used for broadcasting; power amplifying means for amplifying the power of the video and audio signals to a predetermined level to generate amplified video and audio signals; means for selecting either the amplified video and audio is signals or an antenna input signal applied to an ancenna input terminal of the VCR in response to an instruction of the VCR user; and antenna for transmitting either the amplified video and audio signals or antenna input signal, whichever selected, to one or more receiver sets.

2. The VCR of claim 1, wherein each of said one or more receiver sets is a television (TV) set.

3. A receiving system comprising a video cassette recorder (VCR) and one or more receiver sets, the VCR incorporating therein a wireless radio frequency (RF) modulating device, wherein the wireless RF modulating device includes: an RF modulator for modulating video and audio signals read from a magnetic tape by using a predetermined carrier frequency for a channel to output modulated video and audio signals, wherein the channel is a channel that is not being used for broadcasting; power amplifying means for amplifying the power of the video and audio signals to a predetermined level to generate amplified video and audio signals, means for selecting either the amplified video and audio signals or an antenna input signal applied to an antenna input terminal of the VCR in response to an instruction of the VCR user; and is antenna for transmitting either the amplified video and audio signals or antenna input signal, whichever selected, to one or more receiver sets; and wherein each of said one or more receiver sets includes: receiving antenna for receiving either the amplified videoand audio signals or antenna input signal Cransmitted through the sending antenna; and means for demodulating either the video and audio signals or antenna input signal, whichever received, to display a demodulated video signal on a monitor of each of said one or more receiver sets and sound the demodulated audio signal through a speaker thereof.

4. The receiving system of claim 3, wherein each of said one or more receiver sets is a television (TV) set.

5. A receiving system constructed and arranged substantially as herein described with reference to or as shown in Figs. 1A and 1B of the accompanying drawings.

is