Are there oscilloscopes that can have their sample rate increased by doing this?

[Plasmateur]

Let's say I have a pulse delay generator, an oscilloscope, and a signal generator which are tied to a 10MHz clock.

The scope has a sampling rate of 1Gs/s, so dt is 1e-9 seconds.

I have a repeatable waveform generated by the signal generator that is triggered by the pulse delay generator. The scope is also triggered by the pulse delay generator.

The first acquisition takes place, several waveforms are averaged and the data is stored.

I then take a second acquisition, but this time the pulse delay generator offsets when the oscilloscope is triggered, with respect to the signal generator by dt/2.

I then take both acquisitions and interleave them, which should have given me twice the original sampling rate.

1.) Is this method used by anyone here? I'm guessing if this works, it should only be done on equipment that can be referenced to a 10MHz clock.

2.) What is the limit this can be taken to? Would this be limited by the device with the highest jitter?

3.) If you have done this before, what scope did you use and how far above the base sampling rate could you achieve?

I understand this isn't any good for increasing the bandwidth of a scope. It's more of a niche case in which I would need to do this.

[oPossum]

Every DSO with ETS (equivalent time sampling) does essentially what you have described.

[Keysight DanielBogdanoff]

Like oPossom said, equivalent time sampling works this way. There's also a whole category of scopes called "sampling scopes" that do exactly this. It's good for signals that are repetitive and don't vary from cycle to cycle. They are commonly used for optical test.

[David Hess]

1.) Is this method used by anyone here? I'm guessing if this works, it should only be done on equipment that can be referenced to a 10MHz clock.

Like the others say, you have reinvented equivalent time sampling.

2.) What is the limit this can be taken to? Would this be limited by the device with the highest jitter?

It is limited by the trigger to sampling jitter.  50 picoseconds of jitter (20 Gsamples/second) is not too difficult to achieve but better requires attention to detail.

3.) If you have done this before, what scope did you use and how far above the base sampling rate could you achieve?

Typically the sample rate is increased by 5 to 100 times.  Dedicated sampling instruments might increase the base sampling rate by millions or even 100s of millions of times.  My personal record is 500 million and the acquisition took hours to complete; it was more of a "I wonder if this is possible to do" experiment rather than something practical.