Analog Tvs

Analog Tvs

Can the analog pass-through signal in a digital TV converter box be fed through the composite output?

Does the pass-through signal only work through a coax output from the converter box? On my VCR (with tuner) the analog tv signal can be passed through the composite cables.

A baseband composite video signal (or CVBS) contains video picture information only and does not include the audio signal and RF carrier. With respect to analog television broadcasting in North America, an audio signal is combined with a composite video signal and modulated onto an RF carrier to form an NTSC broadcast television signal. It is the RF modulated analog video signal that applies to the ‘antenna’ pass-through option on coupon-eligible converter boxes (CECBs) and not the baseband composite video signal, which has its own dedicated Composite Video Out connection on CECBs.

Your VCR contains an internal RF demodulator to extract the composite video signals (along with the audio signals) so that they can be recorded. The video output from your VCR will be a baseband composite video signal on the (yellow color-coded) Composite Video Out connection. (In some cases, if the VCR is equipped with a mini-DIN S-Video (or Y/C) Out connection, you may also have the choice of using a Y/C video signal.)

As it relates to coupon-eligible converter boxes, the RF-modulated digital ATSC and analog NTSC signals collected by a UHF/VHF television antenna travel along the downlead to the CECB. From there, if the CECB is so equipped, the analog RF NTSC signal is passed through the converter box, unaltered, to the Pass-Through output on the back of the converter box for connection to the RF antenna input(s) on analog TVs and VCRs. The analog RF signal from the Pass-Through output on the back of a converter box should only be connected to an analog “RF” or “ANTENNA” input on a TV or VCR. You should never connect an analog “RF” or “Antenna” television signal directly to a composite video input without first demodulating the RF television signal.

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I am looking for a converter box to combine with a “rabbit ear” antenna that has a HDMI input?

http://answers.yahoo.com/question/index?qid=20090105152519AAEQsmX

Wiki: Composite Video

http://en.wikipedia.org/wiki/Composite_video

Wiki: NTSC

http://en.wikipedia.org/wiki/NTSC

Color Television, NTSC Tutorials

http://www.ntsc-tv.com

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AN734 - Video Basics

http://www.maxim-ic.com/appnotes.cfm/appnote_number/734/