[time-nuts] Ublox F9P multi-band GPS receiver

[Magnus Danielson]

Hi,

On 2019-01-22 14:10, Poul-Henning Kamp wrote:
>> The one thing which is missing is a external frequency input. You can
>> get a frequency output in its place, but it does not fully replace the
>> input. That's where the module vs. chip comes in.
> Consider talking to sparkfun about how they should do the next version ?
>
Well, the actual ZED-F9P module does not have it as far as I can see 
from the uBLOX datasheets. The module has a TCXO next to the actual F9 
chip inside the module, so the issue really needs to ripple back to uBLOX.

Let me be fair about this, for most uses the ZED-F9P module is just fine 
as it is. It's in fact a wonderful module if it delivers everything 
promised. However, for some more unusual uses we really like to input a 
reference frequency that we steer from a good TCXO, OCXO or Rubidium. 
This will have uses in the time-and-frequency community but also for 
some reference base-stations.

As always, as a hobbyist you want to get everything for essentially 
free. The existing module will deliver so many of the previously premium 
functions that used to cost several thousand dollars in OEM price, but 
for a much lower price, we talk about dropping a zero and maybe divide 
by 2 or so.

So, I think SparkFun is kind of limited in what they can do with the 
module. I would not hesitate to solder in on that board if that was what 
was needed for my hobbyist needs. I've done stuff like that before, and 
will for sure do it again. It's uBLOX we need to talk to for this 
feature request.

Cheers,
Magnus