Sources of hum.

pre65 · Post by **pre65** » Mon Sep 09, 2013 5:02 pm

ed wrote: or call a priest

Any particular denomination ?

Post by **Nick** » Mon Sep 09, 2013 7:49 pm

All the AC/DC button does is put a blocking cap in the way to remove DC. Play with the trigger control and you will find that display cleans up.

If it is 60kHz I would not call it hum. but its more than I would have expected from the DAC.

pre65 · Post by **pre65** » Tue Sep 10, 2013 8:37 am

The DAC board is as built (ie standard) apart from a different op-amp.

Any suggestions as to my next step ?

Is it worth getting an AK4396 board to replace the AK4393 board ?

pre65 · Post by **pre65** » Tue Sep 10, 2013 8:50 am

Here is a picture of my DAC, to see if the way it's laid out is at fault ?

Post by **Nick** » Tue Sep 10, 2013 7:46 pm

The problem is, we have not seen what that signal is actually like, and we also don't know what the output of that board is like as standard.

Is it possible the op amp is singing along to itself.

pre65 · Post by **pre65** » Tue Sep 10, 2013 8:50 pm

I'll try the original opamp , if I can remember where it is, and see if it makes a difference.

Post by **Nick** » Tue Sep 10, 2013 9:08 pm

Well, first, why not try and get the scope trigger to lock on the signal?

pre65 · Post by **pre65** » Tue Sep 10, 2013 10:59 pm

Nick wrote:Well, first, why not try and get the scope trigger to lock on the signal?

I'm still trying to find the Babani book that tells me how to use the scope.

Post by **Nick** » Tue Sep 10, 2013 11:11 pm

There are loads of guides on the net

pre65 · Post by **pre65** » Tue Sep 10, 2013 11:15 pm

Nick wrote:There are loads of guides on the net

Fair point.

audio-talk

Sources of hum.

#16

#17

#18

#19

#20

#21

#22

#23

#24

#25