Revision 16 NTSC Vader - Composite Video Mod / Recap - Not working. Worked before Mod.

[cleoo]

I have a Revision 16 NTSC Vader that I wanted to recap and add the composite video mod. Prior to doing the recap and mod, the Vader had bright colors, but had interference and distortion on the display. The sound was fine. After I recapped it and did the composite video mod, I connected it to the composite jacks of video 1 and all I get is a blank screen and a small pop from the TV speaker when I turn on the switch.

 

I bought this Ebay 2600/7800 Composite Video Mod.

 

But I chose to do DIY version.

 

I recapped it following this video guide:

 

I had actually recapped all the components in the video before proceeding on with the composite video mod.

-C241 .1uf

-C243 2200uf

-C214 4.7uf

-C206 820pf

-C207 820pf

 

It was working but was still had some interference and distortion.

 

So, I decided to install the composite video mod.

 

Console5 listed C201 as a capacitor to replace for the 4 switch, but I could not find it anywhere on the schematic. I saw CR201. I saw C200 then looked around for C201, but only saw C202. So, I was unable to change C201.

I additionally changed C242 with a .1uf like at C241.

I also changed the power port.

 

(CONSOLE 5)

For 4 Switch

• All new 2200uF and 4.7uF electrolytic capacitors: C201, C214, C243 (4.7uF caps are radial-type)
• C206, C207: Two new 820pF MLCC capacitors to replace failure-prone styrene caps: Frequently the cause of audio loss (see product images for install photo)
• C241 and/or C242: Two replacement .1uF (or .22uF) "chicklet" capacitors.  Some models have incorrect parts from the factory, or sometimes the original caps fail and cause "sparklies" in the video.  These are the non-electrolytic cap(s) near the voltage regulator.  The .1uF and .22uF are functionally identical for this purpose.

 

Composite Video Mod:

I removed the 3 legged transistor at Q202.

I removed the RF and the 5 hard pins.

I removed R209

I saw some video mod instructions that also removed C209, but they weren't Revision 16 boards, so I left this.

 

Left side of the composite video board:

I soldered the BLACK ground to RF Pin 1

I soldered the YELLOW VID-IN to RF Pin 4

I soldered the BLUE AUD-IN to the bottom leg of R206

I soldered the RED +5V to RF Pin 3

 

Right side of the composite video board:

BLACK GND soldered across the RED, WHITE, YELLOW RCA jack ground points

YELLOW VID-OUT soldered to YELLOW RCA jack pin

BLUE AUD-OUT soldered to the RED and WHITE RCA jack pins

 

Any help would be greatly appreciated. I'll post the pics of the board soon.

[Rom Collector]

Make sure you didn't install any of the electrolytic capacitors backwards.

[cleoo]

Thanks for the suggestion. The capacitors weren't backwards though. Initially, I thought that because C214 had the positive on the bottom of the board. But since posting, I removed the composite mod and re-installed the RF box and connectors. And it was working, but staticky and distorting.

[+-^CrossBow^-]

Just for giggles, try soldering directly off the v-out off the voltage regulator itself. You know that is putting out a solid +5 so there shouldn't be any issues there. Solder your ground along any point around the board or where the RF modulator was anchored to the main PCB along the edges.

 

[cleoo]

Prior to removing the mod, I tested the voltage leading to it on the board and it was putting out 4.94 volts (Same as at the Voltage Regulator, bottom pin). It seemed to be getting power. I'm going to try the mod on a woody 4 switcher and see if that one works. I read somewhere in this forum that Vader's have problems with video mods. I wasn't able to find what the reason was...yet.

 

If the mod doesn't work in the regular way then I'll try that option.