[Coco] RGB to VGA boards, test equipment needed

[Tormod Volden]

On Sun, Sep 6, 2015 at 10:19 PM, Kandur wrote:
> Would these pocket oscilloscopes do for checking video signals?
> If yes, wich one is better? Are there any others under $100?
>
> http://tinyurl.com/p9jx2ec
>
> http://tinyurl.com/ommymqs
>

Maybe better than (much qualified) speculation :)
This is a screenshot from a DSO201 checking the PAL video output on a Dragon:

http://pasteboard.co/skyrH6L.jpg

You can't see the colour burst, but at least you can see it is a video
signal, and you can see where the sync level is.

The next one is from a prototype of the DSO203, it has higher sample
rate but struggles with its analog bandwidth and gain (should be
better in the final products):

http://pasteboard.co/skWp1GG.jpg

So, as it has been said here, these are not great for video signal
analysis, and you're better off getting an old 20MHz analog scope. But
these pocket scopes are very handy for quick field testing in the
lower frequencies. And fun gadgets, some of them have open-source
firmware and you can hack and modify. The DSO201 is just an STM32
microcontroller with an analog front-end, the DSO203 also has a FPGA
for the signal capture. I didn't know about the DSO112, but it looks
like a repackaged DSO201.

Regards,
Tormod