Correct on both counts. Keep in mind that it was common with cross hatch
& dot patterns to get a ghost to the right. Turning down the brite
eliminates most of & & FT can also. Also if the set has AFT or any other
auto color buttons turn them OFF til the set is repaired.
To inject to the 1st IF input you can make a tuner subber.
Take almost any solid state click type VHF tuner. Get Sams for the
set to get the B+ & AGC voltages. Make a supply for B+ & an
adjustable divider for AGC. Ground the AFT input.
73 Zeno
LFOD !
Quote:
Originally Posted by Electronic M
I'm pretty sure what he means is disconnect the detector diode on whichever side is easiest, hook composite video to the grid of the 1st video amp and see what happens...it's a good signal injection troubleshooting approach. If it gives you video then everything between the ant terminals and detector diode is suspect, but if it doesn't give you video then the video amp stages are suspect.
BTW good idea to not crank brightness too high when looking for video if video is weak you'll see it best with the raster slightly brighter than the minimum brightness needed to perceive that the screen is lit...many properly working sets with strong CRTs will totally wash out the video if brightness is set to max.
If you have video, and good IF voltages but no reception AGC might be improperly adjusted.
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