[time-nuts] DMTD to MMTD

[Lux, Jim (337C)]

> -----Original Message-----
> From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Bob Camp
> Sent: Wednesday, February 17, 2010 1:57 PM
> To: 'Discussion of precise time and frequency measurement'
> Subject: Re: [time-nuts] DMTD to MMTD
> 
> Hi
> 
> Thanks for the quick response.
> 
> The impression I've always had of that system is that it is comparing the
> sources two at a time. They can select between a number of sources, but only
> one pair is looked at.
> 

It basically timestamps transitions on all 8 inputs.  The post processing software that looks a the timestamps is what selects either 1 channel (single mixer+offset generator) or 2 channels (dual mixer time difference)

The counters in the FPGA are running at 100 MHz, so they have a basic resolution of 10 ns.