Chosen Solution
I know how to use a multimeter and handle a soldering iron, and I’m not terrible at component level repair, but that’s about the extent of my skill. I have an ancient Hanimex 777 home Pong-type console that I’m trying to get working again. (It’s a bit of childhood nostalgia that I’m trying to revisit.) It came to me with exploded batteries and no video. I disassembled it, thoroughly cleaned everything inside and out (lots of crystalized battery liquid in the battery compartment, and lots of flux and old fashioned grime on everything else), and repaired a power lead coming off the battery compartment. On my first test there was audio (it comes from the unit, not the TV) but no video. Found out the RCA plug and about 3" of the end of the TV cable were corroded so I cut the cable and soldered on a shiny new RCA plug. Inside, the signal lead for the RCA plug was damaged so I desoldered it from the logic board, retrimmed the cable, and resoldered it to make a good connection. Second test gave me video but the game wasn’t coming in clear. The walls, ball, and paddle were scrambled, almost like the game was caught partway between two games. I discovered the switch (to change gaming mode) was absolutely filthy so I scrubbed it clean with a toothbrush and 99% IPA. Afterwards I just kept going and cleaned the entire logic board, both sides, with a toothbrush and 99% IPA. Third test solved that issue but left me with some very distracting white noise. I thought maybe it was a battery issue so I cleaned the DC-In power jack with a tiny brass brush on a Dremel, adapted a modern power supply to feed it the correct power, and tried that way (on the plug with no batteries installed). Same issue. So that’s where I am now. It works absolutely perfectly except for some distracting white noise in the video. On the logic board there’s a small shielded area where the channel selector switch is, and the RF output is right next to it, so I’m guessing this shielded area is where the TV signal is generated and therefore the issue might be in there. Trouble is, I have no idea how to troubleshoot it. The physical repair I can handle; if I know what’s bad I can get a replacement part and affect the change. It’s the diagnosis that I’m weak on. There’s a picture and video here: https://imgur.com/a/JGeeHOK If anyone can help me get a clean image, I’d appreciate it.
=== Update (06/18/2022) === @oldturkey03: I know it’s been awhile but I finally had some time to work on this today. I pulled the motherboard from the unit and gave it a thorough ultrasonic cleaning. After cleaning and drying, I’m pretty sure I’ve discovered the culprit. There’s a or transformer (I think?) which looks completely disintegrated. I didn’t see it before because the board was absolutely covered in flux and I thought it was just flux build-up (which I’m sure was part of it), but after the ultrasonic bath it stands out in stark relief. Now I just have to identify that component, find its specs, source a replacement, and hope swapping it will do the job. I also bought a new output cable, just in case, and I’ll install that at the same time. I’ve added new pics to the Imgur album: https://imgur.com/a/JGeeHOK The bad component is marked 2T1380 and there’s a picture of it in the Imgur library. So far I’ve been unable to learn anything about it; Googling 2T1380 just brings up a bunch of house floor plans.
UPDATE: A clean transformer.
@steve_g first thing I‘d to is to replace the RF cable since both ends were corroded which leads me to think that there is a whole lot more corrosion. Clean the potentiometers in the shielded area of your board as well. Check the underside of your board and I would do a quick resolder of the components. Take a careful looks at all the trace and components and check for fractures, corrosion and yes, solder whiskers as well. Lets see more of the complete console. I had to learn about Hanimex777and being a clone (wonder what they cloned from) Interesting history and great project. Update (05/30/2022) @steve_g take your time. No rush but I love this beast already. little bit of info The 777, would be from around 1977, being an early AY-3-8500 based system.There was also the colour model 7771-C, which used a AY-3-8515 in addition. You do want to check on here for some great info on the RF generation etc. Great read.
