[Lowfer] GPS frequency lock

[David Willmore]

> Ooops, sorry everyone, here's the missing URL.
> 
> http://w3ref.cfn.ist.utl.pt/cupido
> 
> The section you want is: Phase lock a VCXO to a standard 10MHz or to a GPS(1pps) 
> Spend some time there, he has a lot of neat "toys". 

Does anyone here know much about PLLs?  I'm trying to figure out how to lock
my DDS beacon to the 1pps output from a GPS (all in software) and I can't see
a good way to do it.  1pps is awfully slow(or too fast, depends on how you
look at it) and my clock is very coarse (500KHz).  

Anyone want to take this off list and give me some pointers?  I just can't 
see a clean way to do the lock.

Cheers,
David