Owon 7102 Digital Oscilloscope problem

[Geo]

Hi.
For 1+ year now i havea mobile oscilloscope Owon 7102.
Problem is that it has a delay (maybe 0.5...1 sec) on the viewing signal.
For example when i move a coin over the coil of a metal detector and have the scope connected to the Rx coil, i see the change of signal when the coin is far from coil or when i stop to move it. Is this normal for a digital scope???
Another reason not to separate the old analog ..

[Monolith]

Hi.
For 1+ year now i havea mobile oscilloscope Owon 7102.
Problem is that it has a delay (maybe 0.5...1 sec) on the viewing signal.
For example when i move a coin over the coil of a metal detector and have the scope connected to the Rx coil, i see the change of signal when the coin is far from coil or when i stop to move it. Is this normal for a digital scope???
Another reason not to separate the old analog ..

Do you have AQUIRE set on average 128? Set it to sample to get instant response.

[Geo]

Thanks, i will try and inform

[Geo]

Do you have AQUIRE set on average 128? Set it to sample to get instant response.

I tried it.
Aquire was to sample. On average 128 waveform has big delay....
The onle set that gives instant responce is at TrigMod as Slope but this way it can't stabilize the waveform....
I am afraid that the delay is a problem of digital scopes.....

[WM6]

Geo you need to set shortest time /div.

Despite, if you have max. 10M of memory points with your model, you could at scanning time par example 50ms/div, sample with only 20MS/sec and not with declared max. 1GS/sec.

For IB coil to tune it is better to go to spectrum analyzer frequency domain mode (MATH/FFT) which is more informative than usual time domain scope mode.

[Monolith]

I tried it.
Aquire was to sample. On average 128 waveform has big delay....
The onle set that gives instant responce is at TrigMod as Slope but this way it can't stabilize the waveform....
I am afraid that the delay is a problem of digital scopes.....

I also have an OWON, no problems. Can you show a wave form that gives you problems?

[Geo]

Geo you need to set shortest time /div.

Despite, if you have max. 10M of memory points with your model, you could at scanning time par example 50ms/div, sample with only 20MS/sec and not with declared max. 1GS/sec.

For IB coil to tune it is better to go to spectrum analyzer frequency domain mode (MATH/FFT) which is more informative than usual time domain scope mode.

Problem is not how to use beter it for a coil calibration but what happens and it has delay...

[Old cart]

If there is way to shorten the record length( number of samples taken per acquisition) try to set it to 1024 or even 512 points per waveform.

[Geo]

I also have an OWON, no problems. Can you show a wave form that gives you problems?

I will try to give you an example....
I touch tightly the probe and i see a sine waveform at 50Hz. When i stop to touch the probe the oscilloscope still shows the same waveforms for about 0.5 ... 1 second.
On a analog scope when i stop to touch the probe, the oscilloscope stops the same time to shows anything.

[Geo]

If there is way to shorten the record length( number of samples taken per acquisition) try to set it to 1024 or even 512 points per waveform.

I have it at 10k or 100k (don't remember exactly).
Tommorow will try it to 1024 and i"ll inform.
Thanks

[Monolith]

I will try to give you an example....
I touch tightly the probe and i see a sine waveform at 50Hz. When i stop to touch the probe the oscilloscope still shows the same waveforms for about 0.5 ... 1 second.
On a analog scope when i stop to touch the probe, the oscilloscope stops the same time to shows anything.

What is your PERSISTENCE setting?

[Geo]

Ihave enough

[Old cart]

Geo, try the shorter record length. You should always keep it as short as possible for the application. Usually this is 1024 but is 1000 on your scope. Does your scope work Ok when there is a signal? For example do you see noise changing on the screen?

Your problem is when you take the probe away it takes the scope a long time to auto trigger which it must do to recognize that the signal has left. Usually this is not an issue becuase there is signal movement which causes a trigger. You might try to make sure the scope in AUTO and that there is no hold off set, or at least it is set to the minimum which is 100 nS.. On many scopes there are lots of settings that affect things. If you are not completely aware what everything does and where it is set you can have problems. You might try a default settings then set to auto trigger and an appropriate sweep speed and sensitivity setting. Let us know how this goes.

Other hints
Make sure the scope is in single trigger NOT alternate.
For metal detectors always use the bandwidth list of 20 MHz.
Persistence should be set to off usually. ( NOT yours. The scopes!)��
Last make sure auto scale is off

[Monolith]

Ihave enough

Persistence is a great virtue, you obviously have a lot of it.
To set PERSISTENCE on the scope, go to DISPLAY, PERSISTENCE, MULTIPURPOSE, select OFF.

[Geo]

Hi. Sorry but i like to joke a little.
Persist is OFF.
Trigger is in single mode, BW= 20Mhz, auto scale =OFF and Trigger is at auto and record length =1000 (i set it today).
Problems remains. It is not some real problem but I do not like this delay.
I will try to attach a small video

Regards