There are people much more knowledgeable than me here, but from what I can see from your pic it seems that as you said just the electrolytic capacitors need replacing.
Some other precautions such as cleaning the board surface with isopropyl alcohol and/or similar, and then checking if the tracks are intact.
Some other precautions such as cleaning the board surface with isopropyl alcohol and/or similar, and then checking if the tracks are intact.
Nothing wrong there. The Caps are almost certainly ok too.
This is just glue placed around larger Electrolytic Caps to mechanically fix them to the PCB.
This glue can though in my experience become conductive so I would remove it. But nothing else looks amiss to me.
This is just glue placed around larger Electrolytic Caps to mechanically fix them to the PCB.
This glue can though in my experience become conductive so I would remove it. But nothing else looks amiss to me.
Nothing wrong, just the poo glue they used to hold down the caps. There's a major issue with that glue though, it gets conductive. I would scrape it away and use hot glue.
That glue not only gets conductive, but corrosive as well. I've seen capacitors with the legs completely rotten away and tracks dissolved from the pcb because of that stuff. I would temporarely take the caps of the board so you can check underneath and remove all glue, including what has ended up under the caps. When the caps look fine and there is no sign of leakage or corrosion on the leads, reuse them. Measuring them first is better of course when you have the equipment. But as already said, when they look ok and they don't leak, they're probably fine.
The board is likely not ruined, you can see the traces through the glue as undamaged. It may well deteriorate over time without removing the glue. If the capacitors failed the circuit wouldn't work properly and the tops of the caps would probably be bulging...
There have been known issues with this stuff since the early 90's.
As it aged, the dielectric properties changed to form enough capcitance between traces to cause trouble with VHF circuits.
A Sony tech who serviced our broadcast video gear told me they learned it caused problems and had to replace it in the field with a new version.
It's likely the modern stuff is much better and no longer a concern, even though it's still ugly when misapplied.
FWIW, I've never seen it get corrosive as described above, however we can be fairly certain not everyone is using the same glue, so the results will vary.
As it aged, the dielectric properties changed to form enough capcitance between traces to cause trouble with VHF circuits.
A Sony tech who serviced our broadcast video gear told me they learned it caused problems and had to replace it in the field with a new version.
It's likely the modern stuff is much better and no longer a concern, even though it's still ugly when misapplied.
FWIW, I've never seen it get corrosive as described above, however we can be fairly certain not everyone is using the same glue, so the results will vary.
I would probably just put the board back/cover on and forget about it.
Only time I have seen a corrosion problem was in car amps that were subjected to extreme environmental conditions. It can turn very dark looking, if it is even the same as mentioned above.
Can easily do more harm trying to remove it in many cases.
Also, typical hot melt isn’t a good solution, is for paper arts and crafts, will release due to normal humidity in a few weeks. Many commercial products use a urethane glue that looks like it however, so that may be why it is perceived to be the same.
Only time I have seen a corrosion problem was in car amps that were subjected to extreme environmental conditions. It can turn very dark looking, if it is even the same as mentioned above.
Can easily do more harm trying to remove it in many cases.
Also, typical hot melt isn’t a good solution, is for paper arts and crafts, will release due to normal humidity in a few weeks. Many commercial products use a urethane glue that looks like it however, so that may be why it is perceived to be the same.