Maker Pro
Maker Pro

Oscilloscope Help

Sadlercomfort

Ash
Feb 9, 2013
424
Joined
Feb 9, 2013
Messages
424
Hi Guys,

I'm trying to measure a small signal change when i connect a 9v battery to a remote while nothing is pressed, to see how the remote discharges the battery when sitting.

I cant seem to get a good signal on my oscillate and there seems to be a lot of noise. Any ideas?

See a pic:

http://s29.postimg.org/52h888jp3/20160330_141547.jpg
 

shrtrnd

Jan 15, 2010
3,876
Joined
Jan 15, 2010
Messages
3,876
I can't see your picture because of my computer set-up.
Have you set your scope for 'DC'?
 

Sadlercomfort

Ash
Feb 9, 2013
424
Joined
Feb 9, 2013
Messages
424
Yeah its set to DC

8da31c1.jpg
 

BobK

Jan 5, 2010
7,682
Joined
Jan 5, 2010
Messages
7,682
What is it you are measuring on the scope?

The remote will likely draw uAmps when no button is pressed.

Bob
 

Sadlercomfort

Ash
Feb 9, 2013
424
Joined
Feb 9, 2013
Messages
424
Thats exactly what I'm trying to measure.. uA's.

I measured a current draw of less than 1.4uA on a digital multi-meter. I was hoping to confirm/verify my results.

Somehow the lines have disapeared and i can now see a continuous signal, but I still can't see the difference when i connect the battery to the remote.

Perhaps I over estimated the sensitivity of the oscilloscope, it seems to go as low as 20mV/Div. I need something like 1mV/Div
 

dorke

Jun 20, 2015
2,342
Joined
Jun 20, 2015
Messages
2,342
I wouldn't go this way at all.
The standby current of remote controls is sub-mA you wouldn't be able to see any change in the Battery Voltage with a scope.

What you can do is use a sensitive Ampere-meter(μA).
If you don't have a digital one, you can use an old analog Ampere-meter or just a "bare meter"(50μA FS).

Or a sensitive DVM(μV scale preferable ) with say a 1-ohm or 10-ohm series resistor to measure the Vdrop on the resistor and calculate the current.
e.g assuming your Stby current is 100μA
you would get a 100μV with 1-ohm and 1mV with 10-ohm.
 

Sadlercomfort

Ash
Feb 9, 2013
424
Joined
Feb 9, 2013
Messages
424
Yeah think your right dorke, isnt going to work out.

I have already obtained some results in (μA) using a multimeter.. this will have to do!
 
Top