There are two ways you can approach this.
1. You can do a 'save on trigger' session and write a series of screens to your hard drive. This will not be continuous however. There will be gaps between the screens like a motor drive camera series.
2. You can just put more time on the screen, at 2s/div, and get a 20 second screen time, then zoom in as desired. To get the best results, you will need to dial up the samples collected under 'settings' 'options' 'advanced' and also select 'block mode'
You don't mention which instrument you are using. How much detail you will get depends on that. If you were using the ADC 212/3, then you would sample about every 680 microseconds with 20 seconds on the screen, with samples maxed at 32,000.
OK, just saw your other post. With your ADC 212/100 dialed up to 128,000 samples, you would then have 164 microseconds between samples with 20 seconds on the screen.
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