¢VCS FUTURA¢¢2600 VIDEO MODIFICATION¢Version 0.3¢by Ye Olde Atari 8-bit owner¢¢Tools required:¢¢Philips screwdriver¢Small pair of pliers¢Soldering iron and solder¢¢Parts required:¢¢R1 & CAP combo:¢1 x small capacitor 220uf @ 16v¢1 x 1.1K OHM resistor¢¢R2 & R3 combo:¢1 x 10 OHM resistor¢1 x 22 OHM resistor¢¢1 x diode (for 9v)¢¢ Firstly, refer to the Audio modification (see last issue) on opening up your unit. While you are there read up on the same resistor formation as mentioned in the article and reference it to your VCS circuit board.¢¢ Now that you have your board in front of you and are looking at the vertical formation of components you must locate two places on your board:¢¢1) The first is a component labelled as R55, the sixth component from the left hand side of the formation.¢¢2) The second is a location, and will be called point X. Go to the start of the component formation. To the right is a large chip. Point X is the vacant hole just to the right of this chip. This hole lies at the end of a large area of trace that tapers to form a triangle, with the hole at the end, and should be blocked.¢¢¢Work off board¢¢¢R1 & CAP combo:¢¢ Find the negative lead of the capacitor and one of the lead ends of R1 (any one will do). Place both lead ends together and twist them so both body parts are close to each other. Now solder at the top of the twist near the body parts of the components so there is next to no lead between them. Now snip off the twisted lead ends after the solder joint so you end up with two components, a small blob of solder in the middle (minus lead ends just snipped off) and a single lead end coming out of each component.¢¢¢R2 & R3 combo:¢¢ Place both of these resistors together in parallel. Slightly twist the lead ends of both resistors (close to the components bodies) so that it is enough to hold them together. Now solder either side close to the component body parts so you have two resistors in parallel in the middle and two slightly twisted lead ends either side of them. Now snip off one lead end either side of the two resistors, just after both of the solder joints. You should now have two resistors in parallel with a single lead end either side.¢¢¢Work on board:¢¢¢ Solder the diode in parallel with R55. The diode should be positioned to allow voltage to flow top to bottom. It should have a band on the component body on one end and should be at the bottom to show the voltage is blocked.¢¢ Solder the positive lead of R1 & CAP combo to the top of the R55 & diode combo (the positive lead end is the lead on the capacitor side).¢¢ Solder either end of the R2 & R3 combo to the bottom of the R55 & diode combo.¢¢ You are now left with the negative lead end of the R1 & CAP combo and a lead end from the R2 & R3 combo. Both ends will now be soldered to point X. The hole size limits you to one lead end so either solder one of them in the hole and the other in parallel on top or twist both together with one lead slightly longer (so it can go in the hole and the other just outside). Then solder this twist together to Point X (making sure the leads are also soldered together in the process).¢¢ You will have to prevent some wires from touching by deliberately bending them, thus allowing for the shielding to fit on top. You can either hot glue or position the components you have added to secure them safely.¢¢ If you want you can put your VCS together and call it a day. Or you can hook up your bare board with a rom and study the picture, it could be possible that the picture can still be improved!¢¢ Locate your RF modulator (the shiny metal box to the north east of where you have been working) and with the aid of a trimmer you can tweak your picture. Looking at the top of your modulator you will see a hole. Inside is a trimmer (if you are not gentle in hand weight and movement PUT YOUR VCS BACK TOGETHER). I will now describe how it affects your picture:¢¢If you turn it clockwise you will enhance shadowing to the right of an object on screen.¢¢If you turn it anti-clockwise you will enhance the colour smear to the left of an object on screen.¢¢If you turn too much in either direction the picture will fuzz away.¢¢ When tweaking you should first make sure that all your TV controls are set equally as:¢¢Contrast: hides shadowing, shows colour smear/saturation, plus it sharpens the picture while making it grainy.¢¢Brightness: hides colour smear, shows shadowing, plus it reduces clarity.¢¢Colour: increases colour saturation.¢¢ When tweaking it is best to view a solid colour object on screen, with straight edges and try to achieve an equal balance either side of the object (so find a ROM with a decent screen object).¢¢Example:¢¢ Going clockwise with blatant colour smear. As I turn, the colour smearing to the left of my solid colour object will reduce, while at the same time the effects of shadowing will begin to appear to the right, so I will go back and forth to find a balance. At the same time the solid colour object will suffer from an un-even colour distribution over itself, so this will also have to be balanced out.¢¢ To the west of our present position on the opposite side of the board is the colour trimmer which can be used to increase colour to hide any uneven colour distribution of the object on screen. If you trim to increase colour you will also add to the colour saturation, so it will not better the picture quality. If the left side of your object's colour is a slightly lighter shade than the right do not worry.¢¢If you are satisfied you can finish.¢¢NOTE: Most VCS units are adequately set up so tweaking should not really be necessary.¢¢The picture quality you end up with will be worth the effort. Oh yes, the mod does look funny!¢¢¢Any blunder(s) you make are of your own doing, so congratulations!¢
