Can I see what the bottom of your upgrade board looks like? You should just be able to pop off the connections on the front of the board and bend it up.
Audio issue a couple of weeks after Moreplay Upgrade [resolved]
- Thread starter Galluch57
- Start date
I think you have some cold solder joints. You can leave the joints for the LEDs alone, but everything else should be reheated and flowed out.
https://www.youtube.com/watch?v=EN16Pi7pcfk
https://www.youtube.com/watch?v=EN16Pi7pcfk
Yes, those haven't been heated enough and should be reflowed (excluding the LEDs, which take very little heat to solder properly).
Heat the existing solder, provided it has lead and is rosin core solder. Adding more solder will just add more metal that needs to be heated to flow out properly.
You will need to take the board out and show us a picture of the entire bottom of it.
You have excessive current flow where current should be regulated. If there were soldering issues present, it's possible that a transistor or two have shorted out from that fault, and you can check this by setting your meter to beep when you touch the leads together, then touch each pair of leads on each transistor (Q1/Q2-B &C) to see if there are shorts.
It's also possible that your main C4S board is working properly, but that there's a soldering issue related to the balance pot and the input/output wiring there, and the 6V6 grids are losing their ground reference and this is causing extremely screwy DC voltages. I would evaluate this by temporarily soldering one bare wire across the L-Out, R-Out, and ground lugs next to the balance pot. That will provide a DC short to ground, and if your voltages move dramatically, then you know the issues is in the input/balance pot wiring.
You have excessive current flow where current should be regulated. If there were soldering issues present, it's possible that a transistor or two have shorted out from that fault, and you can check this by setting your meter to beep when you touch the leads together, then touch each pair of leads on each transistor (Q1/Q2-B &C) to see if there are shorts.
It's also possible that your main C4S board is working properly, but that there's a soldering issue related to the balance pot and the input/output wiring there, and the 6V6 grids are losing their ground reference and this is causing extremely screwy DC voltages. I would evaluate this by temporarily soldering one bare wire across the L-Out, R-Out, and ground lugs next to the balance pot. That will provide a DC short to ground, and if your voltages move dramatically, then you know the issues is in the input/balance pot wiring.
That is all correct.
Galluch57
New member
One last question before I proceed. I labeled and desoldered all the leads running to the PC board to remove it so I could reflow the board on my work station. How many times can I remove the board without damaging the pads etc.? Seems to me I now have to remove the board again so I can desolder the transistors for testing
The board can come on and off 5-10 times most likely. A lot of it depends on how gentle you are pulling the wires out.
Definitely test all the transistors, I've seen both the PN2907 and the MJE5731A transistors short previously.
Definitely test all the transistors, I've seen both the PN2907 and the MJE5731A transistors short previously.
