The zed-f9p chip has a BATTERY BACKUP input to minimize “Time To First Fix”
On the board is not visible a battery designed for this purpose, is it necessary to use an external battery by connecting it to the pins on the board?
There is not battery. Batteries make shipping/mailing things very difficult and expensive if done legally.
I haven’t seen a schematic, so don’t know if it is wired to an accessible pin, or one typically used in Arduino boards.
With a good antenna, your TTFF is in the order of 30s without a battery.
I saw that the battery is not there
My question was aimed at understanding “why” is not there
It is not necessary to ship the battery
But just design the pcb so that a battery can be installed
It would have been the care of the user to insert it or not
For sure, without an electrical scheme, it’s a problem even if you want to do it yourself
I understand that in ideal conditions the fixing will be achieved in a short time
But you have to understand, that in ideal conditions and with the battery, maybe even better times were obtained
We decided it was not a killing factor in an RTK system, as for achieving cm precision is required to have live satellite data.
V_BCKP provides means of accelerating time to first fix (max 30 seconds improvement), but doesn’t substantially improve time to RTK fix with centimeter accuracy.
It also reduces cost and simplifies logistics as clive1 described above.