Hi and welcome to scope month! My name
is Daniel Bogdanoff and today is Friday,
March 24th which means we are giving
away six 1000 x-series scopes and two
1GHz 4000 x-series scopes. We had a
comment on a previous scope month video
asking if we could gate measurements and
Erin, the product manager for the
InfiniiVision scopes wanted to come
out and show that so I'm going to step
off and bring her on. So it's really easy
to make pulse width measurements when you
have an exactly repeating pulse every
time, but what do you do when the pulse
widths and the pulse characteristics are
different every time. That's where gated
measurements come into play. On the
screen we have a digital burst and we
can see there's seven different pulses
in there that all have different pulse
widths, so how do we actually measure
each of those different pulse widths?
That's when we use gated measurements.
We can see there's a flickering here. We
want to make sure we get a stable
trigger on that. So to do that we want to
use a trigger hold off. So Daniel showed
you how to do this the other day, but
we go into the mode coupling menu and
then select hold off, and I'm going to
set that hold off to 24 microseconds.
Because we're at one micro second per
division, we can see this is about four
divisions wide. So now we have a stable
trigger set up, we can go ahead and start
making our pulse width measurements. So to
do that we go into the measure menu and
then we change the type to "plus width" so
that's going to be our positive pulse
width. Now we can see the scope is making
a measurement on that first pulse there.
The pulse width is about 200 nanoseconds,
but now what do we do if we want to
isolate each of those other pulses? It's
really hard to make measurements on
those so we use the gated FFT to isolate
each of those and make measurements that
way. So to turn on the gated FFT. We press
the magnifying key on the top here. Now
we can see the longer time span along
the top of the screen and the zoomed in
portion along the bottom. And to adjust
that gate, you use the horizontal
positioning knobs. So we can make it a
little smaller and center it using the
horizontal offset. So now we can see it's
making the pulse width measurement on
that isolated first pulse. We already
know that's 200 nanoseconds. So now to
look at the second pulse we use that
horizontal offset to move this gated
window over to the second pulse. Now we have
the second pulse isolated on the bottom
of the screen and we're making a pulse
width just on that pulse. So now we can
see that pulse is 400 nanoseconds and we
can do the same thing with the third
pulse, we see that's a little bit smaller,
it's about 100 nanoseconds, and you can
continue doing the same thing with each
pulse after that. And by the way, you can
also change how the measurements are
gated by using the cursors. So to do that,
you go into the measurement menu and you
select "settings." Then we can go into the
measurement window soft key and we can
see "gated by cursors" as an option. So you
can actually manually move the cursors
around the screen and tell it where you
want to be making measurements. So making
gated measurements is really useful when
you want to isolate different portions
of your waveform and make measurements
on it that way. And you can gain
measurements on any of the InfiniiVision
x-series scopes. You can also gate
FFT measurements, so if you want to see
that, let us know in the comments and
we'll bring Erin out next week to show
that off. Let's go ahead and draw today's
winners. The first two names I say will
be for a 4000 x-series scope and the
other six will be for a 1000 x series
scope. So the 4000 x-series winners are
Igor Czerniawski and Jolyan Shaba. And
our 1000 x-series winners are Noah Aeillo,
Henry Ott, Jun Oh, Francois Barrillon,
William Craig and Robert Ronyecz. So
congratulations to our winners! We will be
in touch with you within three business
days. I also mentioned we'd be showing
some clips from the Test to Impress
contest so we're going to start adding a
clip into each day's scope month video.
Here's the first one. I've been an engineer
for over 20 years now, did a lot of
kind of different interesting projects,
but you know one thing that I did at
home when my daughter was born is this little
guy right here. This is an electronic
stethoscope, and this is a custom piezo
mic element thing that we did- that I
did, and it's got a little DSP and
microcontrollers and things like that,
but basically it records the parent's heartbeat,
strips out all the noise and everything,
and then white noise mixes in and plays
it back out for a little one to go to
sleep. So when I finish this I thought
it wouldn't really take too much to make
a small version of this
that was wireless and battery powered that
connects to a phone that people could
use anywhere to maybe record heart beats,
like maybe in remote areas or remote
countries where people didn't have
access to stuff. And I I thought it would
be cool to make like an open source
electronic stethoscope. And make sure you
get your Test to Impress entry in by
March 31st. Any videos over three
minutes long will not be eligible for
the competition. That's all for today.
Thanks for watching and make sure you
subscribe to the Keysight Oscilloscopes
youtube channel and tune in Monday for
some live scope month QA. I'll see you
then!