![\"tmht_fix1\"](\"https:\/\/blog.system11.org\/wp-content\/uploads\/2016\/11\/tmht_fix1.jpg\")
<\/a><\/p>\nWhile the screen is a complete mess, you can make out a number of ‘OK’ and ‘BAD’ messages.\u00a0 With this many problems and one ROM affected, it seemed best to start with address lines on the ROMs.\u00a0 Immediately the one at J15 turned out to have a disconnected pin 4.\u00a0 The address lines are shared between ROM and RAM near the CPU, which meant there needed to be a broken track somewhere.<\/p>\n
And this is what I found tracing a track just hidden under J17.\u00a0 This is very likely to be the result of someone trying to do a 4 player to 2 player ROM conversion, and being careless with a screwdriver.\u00a0 There’s a somewhat tidy way of fixing small track breaks like this without leaving a big jumper wire on the game.<\/p>\n First scrape some insulation off the track and ‘tin’ some of the copper – liquid flux will help here, just a tiny bit.<\/p>\n Next you need a couple of strands of thin wire – here I just split two off from some fine gauge multicore and twisted them together.\u00a0 Tin those too.<\/p>\n More liquid flux, and solder the exposed tinned wire to the tinned tracks.\u00a0 It’s usually easier to do than this but the socket was kind of in my way, and I didn’t want to go through the invasive and time consuming process of removing and refitting it.\u00a0 This is why we leave some insulation on the wire, to use as a handle.<\/p>\n Then use a razor blade to cut the handle off, leaving a few strands of wire as a track repair.<\/p>\n Tidy up your work by cleaning away the flux and using some masking fluid to cover up the exposed track.\u00a0 Again this can be done a little tidier when you don’t have a socket in your way.<\/p>\n<\/a><\/p>\n<\/a><\/p>\n<\/a><\/p>\n<\/a><\/p>\n<\/a><\/p>\n<\/a><\/p>\n