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peter_scott · 2nd Oct 2019, 4:11 pm

Hi David,

My interlace was poor with the 0.001uF filter but with 0.002uF it's pretty clean and solid but drops out occasionally. I think the occasional frame twitch is due to a noisy height pot and this might be a factor in the interlace drop-outs.

The frame sync at C16 0.001uF on the circuit looks stable to me. See below.

VR9 in the top left is described as an interlace adjustment but it doesn't alter much over the course of its range except when taken to its lowest resistance at which point the frame frequency takes a jump. I think it just adjusts the amplitude of the sync pulse and presumably the effective threshold point.

Peter

2nd Oct 2019, 4:11 pm	#95
peter_scott Dekatron Join Date: May 2003 Location: Edinburgh, UK. Posts: 3,274	Re: Bush TV22 with TC184 B3 converter. Hi David, My interlace was poor with the 0.001uF filter but with 0.002uF it's pretty clean and solid but drops out occasionally. I think the occasional frame twitch is due to a noisy height pot and this might be a factor in the interlace drop-outs. The frame sync at C16 0.001uF on the circuit looks stable to me. See below. VR9 in the top left is described as an interlace adjustment but it doesn't alter much over the course of its range except when taken to its lowest resistance at which point the frame frequency takes a jump. I think it just adjusts the amplitude of the sync pulse and presumably the effective threshold point. Peter Attached Thumbnails __________________ http://www.nostalgiatech.co.uk https://www.youtube.com/c/PeterScott/videos Last edited by peter_scott; 2nd Oct 2019 at 4:19 pm.