My Ongoing Monitor Repair Logs
- Thread starter trashedcabs
- Start date
Agreed ^
Been enjoying this thread, and the straightforwardness of the info here.
It's also great to see repair logs of chassis that aren't usually talked about. I've got a few Neotec's that are on my workbench waiting to be repaired. Some of the info here on the various neotec chassis' you repaired is great info for when I tackle them.
Been enjoying this thread, and the straightforwardness of the info here.
It's also great to see repair logs of chassis that aren't usually talked about. I've got a few Neotec's that are on my workbench waiting to be repaired. Some of the info here on the various neotec chassis' you repaired is great info for when I tackle them.
trashedcabs
Grand Master
trashedcabs
Grand Master
Sanwa PFX KW0606A
Symptom: Transformer whining, then shutdown
I had this chassis out at an event for a few hours and it was reported as broken. Found Q408 shorted, also found D425, R484, R431, Q420, and Q421 bad. Had a suspicion of a bad flyback so I powered it up without the flyback primary connected and it was now working. Reconnected the flyback pins and all those components failed again. Replaced bad flyback and all those components again to fix.
Symptom: Transformer whining, then shutdown
I had this chassis out at an event for a few hours and it was reported as broken. Found Q408 shorted, also found D425, R484, R431, Q420, and Q421 bad. Had a suspicion of a bad flyback so I powered it up without the flyback primary connected and it was now working. Reconnected the flyback pins and all those components failed again. Replaced bad flyback and all those components again to fix.
Did you try one of the replacement flybacks from tecknoservice or one 'rescued' from another chassis ?
trashedcabs
Grand Master
I used one from another chassis that is a spare I haven't had a chance to look at yet. The teknoservice ones are way overpriced when you can get an entire PFX chassis from Xianyu for under $30.
trashedcabs
Grand Master
MS8-29
Symptom: Horizontal twitching, deflection protection being triggered randomly
I noticed if I maxed out H Subsize and the H Size pots the twitching problem went away, or if I maxed out the SPC control which is also connected to H size the problem would go away on the top and bottom. To me this indicated there's an issue in one of these circuits. Not many components in those circuits so checked every one and all tested good, so decided to revisit it later. Started working through the horizontal output section and found a cold solder joint on R546, reflowed this to fix the protection fault.
Twitching still present so kept working through the H output section. At this point since I checked everything I suspected two possible components: the EW transistor Q408 or the opamp on the pincushion board. I used freeze spray to freeze both and as soon as I hit the opamp the twitching went away. I ordered a new one and am waiting for it to arrive.
Symptom: Horizontal twitching, deflection protection being triggered randomly
I noticed if I maxed out H Subsize and the H Size pots the twitching problem went away, or if I maxed out the SPC control which is also connected to H size the problem would go away on the top and bottom. To me this indicated there's an issue in one of these circuits. Not many components in those circuits so checked every one and all tested good, so decided to revisit it later. Started working through the horizontal output section and found a cold solder joint on R546, reflowed this to fix the protection fault.
Twitching still present so kept working through the H output section. At this point since I checked everything I suspected two possible components: the EW transistor Q408 or the opamp on the pincushion board. I used freeze spray to freeze both and as soon as I hit the opamp the twitching went away. I ordered a new one and am waiting for it to arrive.