[time-nuts] Re: Affordable 160 GHz Sampler

[Magnus Danielson]

Hi Mike!

On 2021-09-01 19:42, Mike Monett wrote:
> Conventional samplers for home brewers usually go to 1 GHz. The SD-32
> sampler for the Tektronix 11801C mainframe goes to 50 GHz. The HP 110GHz
> oscilloscope costs around $1.3 Million USD, with a 10-bit resolution. Very
> impressive.
>
> https://www.youtube.com/watch?v=DXYje2B04xE
>
> I have invented a new sampling technology that promises 160 GHz bandwidth,
> yet is affordable to home experimenters. If you can afford an IPhone or
> IPad, you can afford this sampler.
>
> This technology is not pie-in-the-sky. I made a basic 5 GHz version for the
> University of Ludwigshafen, Germany, and they were very pleased with the
> results. I am attaching images of the response compared to a
> Tektronix 1502 TDR and the pcb as proof.
>
> This was the first prototype, and I have made significant improvements
> since then.
>
> I have two questions for the time-nuts group:
>
> 1. where would a sampler with this bandwidth be useful?
>
> 2. where can I find signal sources at these frequencies to check the
> response?

Undersampling still has it uses at these frequencies. Combining it with 
a suitable step-recovery diode or non-linear transmission line to 
compress pulses (such as those designed by Picosecond Pulselabs), you 
get a rise-time source to do TDR. TDRs is typically limited by the 
timing source rise-time rather than the sampling rise-time/bandwidth. We 
have signals pushing up to those levels on the optical side, but most is 
RF signals which is usually easy to shift in frequency. The TDR is the 
one complementary measurement beyond network and spectrum analyzers that 
really makes a difference, just that few realizes. For 100 GE for 
instance, we see 25 Gb/s lanes out of the module electrically, those is 
measured routinely. The market for the full serialized speed is fairly 
low still, very few needs to do the measurements, and you work 
differently with those signals because of how short stretches of PCB you 
can go. The one thing is to look at signal integrity analysis, and in 
that lies jitter measurement and jitter measurement analysis. It used to 
be black art, but now basic support comes with many scopes, but their 
processing is usually still a fair amount of black art for the usual folks.

Cheers,
Magnus