[time-nuts] Software Sawtooth correction prerequisites?

[Angus]

On Fri, 11 May 2007 22:11:39 -0700, you wrote:

>> Define cheap.
>> You can already get essentially single chip TICs with a resolution (and 
>> accuracy) better than 100ps for around 100 Euros or so.
>
>Has anyone in the group tried one of these? I would very
>much like to see the results.

The acam TDC-GP1 (~250ps res) and TDC-GP2 (~50ps res) were around 23
and 15 euro respectively when I checked with them last year.

I had been planning of trying a GP1, but have not done much on it
recently. It seemed like it should be fairly straightforward to do a
small module to accept the two pulses and spit out the results to a PC
- much cheaper than a counter, even if generally less flexible.

>> However sawtooth correction is cheaper than using a hardware variable 
>> delay line.

Some sort of hardware correction is also quite useful for feeding a
good 1pps to other equipment that may not remove the sawtooth
themselves, and allows easy checking of any effects of the sawtooth on
them.

Angus.