Atari 2600 light-sixer composite/s-video AV mod dim on first powerup?

unusedowl · October 16, 2016

I recently purchased a pre-assembled 2600 AV mod kit from electronicsentimentalities. I had no issues with the installation. The board was installed into a Taiwan light-sixer (late 1977, RevB.CO10433, not 2600A). The installation was done per the documentation and verified that everything is clean with no shorts. The 75 Ohm resistors on the composite jack+Ground and Luma+Ground are also in place per the documentation. I am using Composite video output.

It seems like the image is extremely dim when the system is first powered on. If I power off the system and immediately power it back on, the brightness/contrast is where I would expect it to be.

Prior to the install of the AV mod, I replaced all of the caps in the system with a cap kit from Console5 (https://console5.com/store/atari-2600-total-refresh-kit-new-capacitors.html). I have not replaced the 4050 IC.

Any suggestions about other remaining caps that may need to be replaced or is this an issue with the AV board?

The only other caps that need to be replaced are C215 and C216 (Cap. Epoxy Dipped .068uF 100V), not sure about C217/C218 -- or if these even matter?

Thanks for your help

unusedowl · October 20, 2016

Update: I've replaced the 4050 IC and cleaned up a few of the solder joints. The image does look a little cleaner, but the double-power-on is still required to get to where it needs to be. electronicsentimentalities suggested it may be a weak TIA. I have an order for some .068uF 100V caps, so I'll try replacing those next.

This system needs some TLC.