Video Transcript
Troubleshooting Strategies
4m 27s
0:08
Welcome back! Let’s continue.
0:12
We’re going to open up our Audio Player and we’re going to play some classical music,
0:18
and just for the sake of our example we’re going to hit Loop so we can continuously have this music playing.
0:24
Now in our example our design doesn’t have any loudspeakers hooked up to it so you can’t hear the audio,
0:31
so actually this is a good time for us to go over the Hover Monitor.
0:35
When your system is running on a Core, you can hover the mouse over any input or output
0:39
and you’ll get this little RTA meter that will appear above the signal at any given point.
0:44
So if you put it over here, or here, here, any time you hover over it and you’re on the Core, it’s going to run.
0:52
Now, if you notice, when you move your mouse away from it, the Hover Monitor disappears.
0:57
But if we hover over and we click this little Pin here,
1:00
it will stay pinned to your Schematic even if you move your mouse away.
1:05
And then if you click the Unmute button,
1:07
the audio will then play through your computer’s onboard loudspeakers.
1:11
Okay, let’s set up a little possible scenario. Let’s go into our Audio Player and hit the Mute button.
1:18
And let’s pretend that we don’t remember that we hit the Mute button.
1:22
So now we’re sitting here looking at our design, and we don’t know if the signal path is broken,
1:27
if the amplifier has failed, or if there is an error in the Audio Player, it really could be anything
1:33
all we know is that it’s not playing any music.
1:36
So let’s take our Signal Injector and inject White Noise into our system.
1:41
If we connect it to the output of the Parametric Equalizer, then we hear the white noise,
1:46
so we know that our amplifiers are probably fine.
1:49
So let’s inject some noise into the output of the Audio Player– that still sounds good.
1:57
That means that the Parametric Equalizer is probably fine too.
2:00
The only possible point of failure is your audio player, and if we crack open our audio player
2:05
yup, there it is. There’s your problem.
2:08
You can see how this injector is a really great tool for quick and easy troubleshooting.
2:14
Now, let’s take our injector out, and we’ll go over the Signal Probe.
2:19
Now the Signal Probe works in the opposite way – rather than inputting noise into the signal,
2:23
it extracts the signal for detection. Now let’s wire our Signal Probe to our RTA,
2:29
so that we get a complete graph on the audio wherever we attach the Signal Probe.
2:34
Now we can use the Signal Probe in much the same way we used the Signal Injector.
2:39
Let’s simulate another issue. First let’s move this probe over, and load our design to the Core.
2:47
And then we’re going to open up our Audio Player, and play some music again. Close that.
2:55
And then let’s create some distortion on our Parametric Equalizer.
2:59
Let’s do that, that should sound pretty crunchy.
3:05
Now let’s pretend that we don’t know why our audio sounds so bad.
3:08
We can use our signal probe to hunt down the source of the problem.
3:12
Alright so first we’re going to open up our RTA so that way we can get a visual representation
3:17
of anything we have our signal probe connected to. And on top of that let’s go ahead
3:22
and pin open our hover monitor and unmute it, that way we can hear anything that we
3:28
have our signal probe connected to. So, next, let’s go ahead and go hunting for our problem.
3:34
First let’s connect our Signal Probe to the output of our Audio Player – that looks and sounds pretty good.
3:41
So let’s go ahead and take that off and connect this to the Parametric Equalizer’s input
3:48
alright, still. We’re still looking and sounding really good, so let’s disconnect.
3:52
And let’s connect our Signal Probe to the output of the Parametric Equalizer – aha!
3:59
That sounds pretty crunchy, that must be where our problem is.
4:03
And if we open up our Parametric Equalizer and we click the Bypass, aha
4:10
our RTA returns to normal, so our problem must be in our Parametric Equalizer.
4:15
You can see how easy it is to diagnose some specific components with just these two tools,
4:20
without ever having to disconnect your design leaving your signal path untouched.
Lesson Description
Troubleshooting Strategies
4m 27s
This video teaches you how to implement the various Test and Measurement tools to troubleshoot your audio and identify the source of problems in a signal path.
Tips and Definitions
Troubleshooting Strategies
4m 27s
Hover Monitor: A miniature RMS meter that appears when the mouse hovers over an input or output pin, displaying the audio signal at that point. The hover monitor can be pinned open and unmuted to be sent through your computer’s speakers.
Signal Probe: This component contains a tool that can be attached to any input or output pin, which will duplicate the audio at that point and send it to whatever is wired to the Signal Probe component.
Downloads and Links
Troubleshooting Strategies
4m 27s