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Old 07-07-2015, 09:39 PM
Findm-Keepm's Avatar
Findm-Keepm Findm-Keepm is offline
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Quote:
Originally Posted by rca2000 View Post
This sounds a LOT like the loss of the video bias voltage to the collectors of the V-out transistors on the CRT board(possible one or three IC'S istead). This is around 200 volts, sometimes as high as 250, sometimes as low as 170. it almostr ALWAYS comes from the flyback--through a rectifier and cap.

Thee is a resistor in line with the diode from1 ohm to 10 ohms usually.. and it sometimes OPENS, sometimes due to a shorted diode. . As a result...the cathode does NOT get its "positive bias" and tends to float towards ground through the driver. This results in excessive broght ness and weak, often negative video.
+1 - the diode, the resistor or both. NTE552, we used an RCA diode (Thomson made BYV26D/E, 1A, 800V or so, fast recovery).

As to the image rotation, it's set by modern digital cameras in the EXIF file. AK and VK for some reason either strip it, or reassign landscape/portrait. No worry - we all need the exercise...altogether now..and a TILT, 1, TILT, 2, TILT, 3...
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