So Some unfortunate event, I fried one of the amplifier boards on my nap 110 when trying to repair my power switch Led. Not sure if the fault was from me using the incorrect resistor or making some sort of mistake replacing the caps on that board. The day before I recapped the left board and power supply and had no issues. Played wonderfully. I was thinking that maybe one or more of the new tant my have failed or some other component? Now that I have replaced the led and am using the correct resistor ( 3k3) Is it possible to place the left board in place of the right one and power it on with 1 board ? What should I be checking ? Does anyone have a list of components for those boards ?
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Nap 110 amplifier board failure
- Thread starter Milspec1
- Start date
The position of the boards should make little difference as the power is fed directly from the reservoir caps as I recall. You can check continuity of the power rails with the amp off, you should have continuity from positive of one board to positive of the other, negative to negative and the 0 volt returns; green to green on each board. Also check you have the screen on the input side on the correct terminal as these are the 0 volt returns from the input stages. If that's all good then check the speaker outputs with a meter to see what dc offset you have (with no speakers attached) and the amp switched on. You can check the rail voltages at this point too. You should be able to get your meter probes on the board plugs without disconnecting anything. Do not run the amp with only one rail powered as the protection circuits will kick in! Good luckSo Some unfortunate event, I fried one of the amplifier boards on my nap 110 when trying to repair my power switch Led. Not sure if the fault was from me using the incorrect resistor or making some sort of mistake replacing the caps on that board. The day before I recapped the left board and power supply and had no issues. Played wonderfully. I was thinking that maybe one or more of the new tant my have failed or some other component? Now that I have replaced the led and am using the correct resistor ( 3k3) Is it possible to place the left board in place of the right one and power it on with 1 board ? What should I be checking ? Does anyone have a list of components for those boards ?
It will be fine to run just one amp board to check the ps voltages ,should be about 35+ 0 35- dc. bare in mind the reservoir caps might still be charged with no load ie an amp board attached.
I sounds like you have shorted a power transistor as the 3 w wire wound resistors have heated up.
When I have repaired this circuit that fault usually takes out a few other transistors so you end up removing and checking the hfe on each on compared to the data sheet.
I sounds like you have shorted a power transistor as the 3 w wire wound resistors have heated up.
When I have repaired this circuit that fault usually takes out a few other transistors so you end up removing and checking the hfe on each on compared to the data sheet.
I check continuity and everything seemed ok. So installed the one board and it was fine. No high DC on the output. I think I must have connected something wrong. I could not see anything out of place on the boards . Funny thing is, now the led is working I find it a bit too bright. Sometimes things are better left alone.