Atari 2600 4 Switch TFW8b Composite Video Mod

Old page follows TFW8b mod install guide.

The corner of the PCB (PAL) we are interested in. Before.

Q201, L201, R222, R209, C209 and RF modulator removed (PAL)

NTSC is slightly different , Remove R209, Q201/Q202 (label changes, location doesn’t) L201 and RF box

PAL PCB shown. Conections for both PAL & NTSC PCBs are the same. Video mod installed. Use a cable tie or sticky pad to secure the PCB.

And a cable tie or hot glue is a good idea here.

Want a PCB.. Get it here

Now back to the old page!

 

Atari 2600 (PAL) Composite Mod

(Transistor based)

 

It’s been a long while since I modded my own 6 switcher to S-Video out.. Way back when, I tried a selection of mods, from a bunch of resistors to transistor and finally chippage (CD4050 i think)

Only the CD4050 gave an output that I found acceptable for my own woody. But after seeing some posts on twitter of a transistor mod, I thought it was time to give it a go again as I had a Vadar waiting for it’s new home. So anyway, I got a couple of transistor mod’s from a kind chap on twitter that he had use himself to give a good output on his Jr. So what do I have to loose right?

 

Atari 2600 4 switcher PAL Darth Vader PCB with Tin Hat removed

Donor PCB via dude on twitter. The results on his Jr look great.. Can’t wait 😀

Skipping a load of pictures as the disappointment is just around the corner

Terrible

Terrible

And on a different TV.. Lemon, Terrible

Tried the second PCB sent to me, you know just in case. Went as far as trying to remove any noise from the switch mode PSU.. Made no difference 🙁

 

Sod it I thought. I’ll make my own. The donor PCB used 3 resistors and a something or other transistor. The mod I know of used two transistors and a 2n3904 and I know I’ve got a tray full of those.. Time to get on with it 😀

 

 

Top tip. Make something that’ll work and then make something that looks tidy before you forget what you did!

Tiny 😀 Anyone trying to copy this. NOTE: Only one drill hole required. #Handy 2k2, 3k3, 2n3904 and thats it.

 

Bit’s and bobs removed… RF modulator, R222, R209, C209 and Q201

Added a bit of copper to reduce noise (well it might)..

 PCB, Copper soldered to GND pads, Hot glue, Paper, Hot glue PCB sandwitch 😀 – Yum

Not so tidy PCB used for this install (I’m keeping the nice looking on for me.. HA!)

Tin hat reinstalled. BTW, the video out cable is secured in the existing strain relief with the aid of some hot glue

Yay.. Thats more like it 😀

Do you know, for such a simple mod thats a bloody good result. Would I use a CD4050 on future mods, well maybe not. I’ll have to try both side by side at some point IN THE FUTURE.

And I’d also like to find out of the 3 resistor mod works ok on a Jr and not a 2600. The inscuction said it would work, but my results proved different in this case.

Thanks again to twitter user for his donation. I’ll revist it as soon as I pick up a Jr ;D

I went back to this a second time and added the 75r resistor over the cut track. Composite video expects 75ohm impedance, it’s not made a noticable difference on my sets, but it is the “correct” way. 75r’s are the future

Can’t be arsed to make your own? Click here ot buy a pre-built PCB.