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Old 11-27-2021, 07:12 AM
vortalexfan vortalexfan is offline
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Join Date: Sep 2018
Location: Northern Indiana
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Quote:
Originally Posted by Electronic M View Post
That's not how it works let alone a valid test. The IF input takes an AM modulated 41MHz ish RF carrier. The yellow composite video output of a DTV box isn't ANYWHERE close to being that.

If you want to inject baseband composite video you can only do that at the output of the video detector diode in the TV (ideal injection site) or points in the video amplifier chain between that and the CRT.

The IF system will ONLY pass IF signal. It will NOT pass composite video.
Ok, then how do people like Shango and the others that I've seen repairing TVs on YouTube use a composite video signal to diagnose the functionality of the tuner and IF on their TVs when they're working on them?
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