Afonso Teles

Hi Cyril,

Have you tried selecting one the of the MDO3xx4 models? They should be similar.

Sounds like the AFG1022 might be a good match to your needs: https://www.tek.com/en/datasheet/arbitrary-function-generator

Hi Pablo,

IQ data has half the sample rate (but double the data per point, so still same amount of data), hence the 625 MS/s sample rate is enough to cover a 500 MHz span,

Before computing the FFT, you should recreate the IF, here's a good description of how to do that:https://panoradio-sdr.de/how-to-convert-between-real-and-complex-iq-signals/
 

That's interesting, might hint that your acquisition hardware is good but some of the SPC hardware is bad.

Details on how to use the built-in instrument diagnostics are on page 4-26 of the service manual: https://www.tek.com/en/oscilloscope/dpo70000-mso70000-manual-6

Hi Pablo,

The TIQ format is not publicly documented, but I suspect it's single precision floating point (32 bit) or 16 bit integer data, with samples interleaved as you said.

Let us know what you find!

Hi Farren,

I think that's unlikely, the DeoxIT probably cleaned off some gunk that was increasing the resistance of the pot, now it's back to normal (worth testing it to make sure though).

It's possible that's just the intensity that it was designed for.

You should check the bias of the Z axis amp and the HV section, those being off would explain what you're seeing too.

Hi Farren,

It's normal for the resistance of a pot to go down after cleaning it.
If the intensity is too low then you should check the Z axis adjustment pot (there should be a procedure for adjusting it in the manual).

Hi Jonathan,

It shouldn't be a firmware version problem, but here's the latest version if you wish to upgrade: https://www.tek.com/en/support/software/firmware/tds3000-and-tds3000b-series-firmware-fv341

Pages 3-64 through 3-66 discuss configuring and troubleshooting the RS-232 connection, I would suggest starting there.