So I just finished cleaning my Color Classic boards that were very dirty in the ultrasonic cleaner and now when I go to boot them neither boot!
- Power Button on KB works for both of them
- HV turns on and display turns on with the grey background
- No Chime
What part could the cleaner have broken? I have replaced the crystals and the roms were not present during cleaning. Are there any parts that are particularly suceptible to the ultrasonic?
Any help would be great!
Did you allow the boards to touch the bottom of the tank? That should be avoided as it puts a huge amount of vibration into the board.
Ultrasonic cleaning works by cavitation: small bubbles are created and collapse, blasting debris from hard surfaces. Vibration of the workpiece is an undesired side effect and must be minimized. Cavitation can be a very powerful force: it can even produce temperatures several times the surface of the Sun, as seen in sonoluminescence.
Besides crystals, ceramic capacitors could also be negatively affected by vibration. They might have developed shorts which would show as a low resistance (< 10 Ω) or beep with a continuity tester. It is also possible to damage IC bond wires with vibration.
Nope they sit in a basket a couple of inches off the bottom. I will check some ceramic caps next I guess. Hopefully its not an IC!
Did you remove any/all of the socketed chips? Leaving them in allows the solution to build up in the sockets and that could cause damage. I am assuming you used distilled (ionized) water and not tap water? What cleaning solution did you mix with the water?
Hopefully if you did damage an IC is isn't an ubobtanium one like your SWIM or one of the other custom ASICs.
Yup all socketed chips were removed beforehand.
And used de-ionized water with Shesto UTFLU05 flux and pcb cleaner from Element 14. Let everything dry for 4 days as well.
Thats what I am hoping for as well. Going to reflox some chips and see if I find any bad solder joints.
Something weird happens with the power on these... Leave it plugged into the wall for a day or so and try it again.
A bit of an update. I got 1 of the 2 boards going. It was bad connections on the ram chips. Figured it out after putting in the external ram sticks and it chimed. Reflowed it and its now away.
There is still an issue with the analog board ( the original fault ). Can anyone tell me where a test point is for the B+
I have a working board and want to compare them to see whats going on.