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Not guilty hehehe.😁 Nice work Bob. Great read,and as always I am none of the wiser lol. If only I had Half a brain!

Brilliant work bob and more great detective work .love the liqourish allsort terminology too!😁

Haven't done a good horror story for a while and as the Mecca's been off the air this one would be a good 'welcome back' to the trials and tribulations in the workshop. This one came in with a few parts missing, a couple of triacs, T60/61 and the usual corroded resistors. It also still had an old battery on it! IC9 (74LS138) and IC24 (74LS12) were both corroded as were the RAM sockets. Once all the bad bits had been replaced and powered up it booted (big surprise) but stopped at a 'MUX Clock Fast' failure. This was due to the timing components around IC10 (555). On the next boot it looked like all was good but there were no lamps at all. This was caused by IC21 (8602) being faulty. The next fault was incorrect button operation and this turned out to be IC22 (4049). Another triac was also faulty and quite a few of the 0.1uF liquorice allsort caps were falling apart so they were all changed. 5 triac driver transistors were also faulty (BCX38). As the corrosion had got in to all the triac pads and gone to that horrible grey crumbly stuff they all had to be removed, pads cleaned and resoldered. No easy task as they are a devil to remove. Back on test and it then wouldn't boot?? The diags showed a Mux clock fast failure again. I had already changed all the timing components and the 555 was running bang on at 500Hz. This time it turned out to be a bad joint on R85 which supplies the 100Hz pulse. Not sure why that should give that error but hey ho it was now sorted. So back to the test machine and all the tests run perfectly, so shut the back door and put a coin in. All the alarms go off and the machine locks up!! Back to the test rig with the diagnostic software and no sign of any problems when operating the coin switches?? I've seen something similar to this before and it was due to bad RAM and sure enough that's what it was. Just goes to show you can't trust the diags for everything.

Just right for a ploggy dx???