Restoring the TI 99/4A, ep. 3
Video hookup
In the previous episode, I got a live console and was able to test TI Basic as well as a few cartridges, connecting the PAL modulator to a modern LCD TV. It worked, but the colors were wayyyyyyy off.
Now, this is a European console with a TMS9929 VDP, and a 6 pin DIN video output socket, providing component video (YPbPr) with sync on Y. It was a pretty simple job to build a component cable with 5 RCA plugs, by beheading a Playstation cable and soldering a DIN plug instead.
I finally hooked that into a RetroScaler2x, and got beautiful HDMI output 
.
It worked beautifully, the boot screen with its rainbow stripes on cyan background brought fond memories. Small TI BASIC programs and game cartridges brought me back 40+ years ago. Wonderful time machine!
Kids come in, trouble is there!
One of the secret goals of this renovation was to put the console in the hands of my kids. My son played a while with Parsec, and then my daughter tried Alpiner…
And there, right in the midst of the game, the console 100% froze again, with the image still displaying, and a continuous tone playing. Not good.
I let it cool for several hours (the power supply board appears to be heating way more than I’d love it to after maybe 15-20 minutes of play), and I’m now back at the initial symptom: continuous random tone at startup, no display. 
Back to the bench!