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Heatercathodeshort · 26th Feb 2015, 8:25 pm

Hello again Mark,
My therapist is paying an emergency visit tomorrow morning..
OK I have posted the vision IF chain and video amplifier minus the sound channel. The two resistors you mention are in fact inductors, L17 L19. Also check L18 on the top tag panel all in the video amplifier and should read S/C. I bet one or both of them is O/C. I had this recently with the earlier 1805.
An audio signal fed to pin 1 of V6 should produce black 'disturbance' bars on the screen that can be adjusted with the brilliance control. Start here and get this right first. The chokes can be shorted as a test. John

26th Feb 2015, 8:25 pm	#89
Heatercathodeshort Dekatron Join Date: Jun 2005 Location: Warnham, West Sussex. 10 miles south of DORKING. Posts: 9,147	Re: Marconiphone VRC74DA Hello again Mark, My therapist is paying an emergency visit tomorrow morning.. OK I have posted the vision IF chain and video amplifier minus the sound channel. The two resistors you mention are in fact inductors, L17 L19. Also check L18 on the top tag panel all in the video amplifier and should read S/C. I bet one or both of them is O/C. I had this recently with the earlier 1805. An audio signal fed to pin 1 of V6 should produce black 'disturbance' bars on the screen that can be adjusted with the brilliance control. Start here and get this right first. The chokes can be shorted as a test. John Attached Thumbnails