Repairing ZX Spectrum +2A, composite video mod

I have purchased ZX Spectrum +2A to my collection and as with +3 decided to add a composite video out.

First what I did I made this RGB mod to get s-video out, by:

1. Removing the 12V from pin 1 by removing resistor R44 (should be the same for +2A, +2B and +3, and very close to the RGB connector).
2. Adding this circuit

Also detached audio from video by removing C24 and shorting from R46 to R56:

I got the video out and it seemed ok at first, but when doing self-tests the result was a washout picture:

ZX Spectrum +2A/+3 Schematic:

Z70830

ZX Spectrum 128K video fixes and video cables:

ZX Spectrum 128K video fixes and video cables

Some useful links:

ZX Spectrum 128k +2 repairs

Removing Blue/Yellow Ghosting from the 128/+2’s Video Output

 

https://sites.google.com/site/lost8bits/sk/sk-zx-spectrum/sk-datacoder-fix