I was Composite AV modding 2 Intellivisions, and now neither have picture or sound

[livingonwheels]

I used a kit very similar to the kits pictured below. I've done these AV kits installs a few times before without issue, it's a very easy procedure. Both consoles were working fine before the install. I started with an Intellivision I. Upon completion, no picture, no sound (but you see the TV screen turn black). Double checked everything, all fine. Got fed up after an hour or so of troubleshooting and removed the kit from the Intellivision I console. STILL no picture or sound. I installed the same kit into an Intellivision II (very stupid mistake). Same thing. No picture, no sound. Even with the kit removed. Something must be wrong with this kit. Any ideas what could have blown on both these consoles? I see no physical damage anywhere on either board.

[+wongojack]

Tagging @-^CrossBow^- who has a TON of experience and might be able to help.

[ApolloBoy]

Do you have any pics of your work?

[+-^CrossBow^-]

I've never had these kits cause any issues like what is being described. But I also never liked their output quality either and that is why on the Intellivison consoles I'm ONLY offering Crayon's boards now since they output much better quality and much more consistent composite output along with the s-video and RGB. And they only cost me about $5 - $10 more per board vs the composite only kits in the past and to me, getting good and consistent results each time is worth that small extra cost.

 

But... @livingonwheels as you now how two dead Intellivisions it is time to troubleshoot them a bit to see what is up. On the model 1 units the black screen condition is usually caused by one or both of the twin 3906s transistors going bad and yes it can suddenly happen. It can also be caused by the clock frequency being too far off that the console isn't able to function logically. You need a Freq counter to verify this. There is a variable capacitor located just below the U10 color IC chip that sets and adjusts this. The model II has one as well, but most of the model 2 units I've seen, actually do NOT have the C2 variable cap and it appears to be locked.

 

[livingonwheels]

I'm not near my consoles at the moment, but here are pictures of exactly how the mod was done on the Intellivision 2 (it has been totally removed and cleaned up at this point). I had yet to drill any holes for the plugs.

 

https://postimg.cc/B85Ftdcw

 

https://postimg.cc/rzZrdGxc

 

Edit: I do have that adjustable dial below the U10 color IC chip that you mention (on the Intellivision 2)

 

Edited March 22 by livingonwheels

[ApolloBoy]

4 hours ago, -^CrossBow^- said:

I've never had these kits cause any issues like what is being described. But I also never liked their output quality either and that is why on the Intellivison consoles I'm ONLY offering Crayon's boards now since they output much better quality and much more consistent composite output along with the s-video and RGB. And they only cost me about $5 - $10 more per board vs the composite only kits in the past and to me, getting good and consistent results each time is worth that small extra cost.

I did try one of these AV mods out again recently since it's the only mod that works with the System Changer, and I was pretty quickly reminded of just why I haven't tackled one of these in so long. I wound up adding a 1000 uF filter cap which cleaned up almost all of the noise, but it's still got some pretty severe ghosting that I don't think is fixable with this mod.