Hello Everyone! I am interested in designing a Pi hat PCB to be compatible with a timing GPS PCB design that I have seen used in a number of places. I have found an “okay” digram, but if anyone has already made gerbers for this thing, I would greatly appreciate it. - Diagram: https://files.millerjs.org/misc/timing_board_PCB.jpg <https://files.millerjs.org/misc/timing_board_PCB.jpg> - LEA-M8T using this format: https://files.millerjs.org/misc/LEA_M8T.png <https://files.millerjs.org/misc/LEA_M8T.png> - Trimble Resolution T: https://files.millerjs.org/misc/trimble_resolution_t.png <https://files.millerjs.org/misc/trimble_resolution_t.png> Even the relatively new uBlox RCB-F9T uses it, calling it an “industry standard form factor” : https://www.u-blox.com/en/product/rcb-f9t-timing-board <https://www.u-blox.com/en/product/rcb-f9t-timing-board> In the RCB-F9T documentation they have a very nice diagram of the module that surely came out of something like Altium, but I can’t find any files to replicate it - https://files.millerjs.org/misc/RCB_F9T.png <https://files.millerjs.org/misc/RCB_F9T.png> Any help would be greatly appreciated, I think one of the biggest things holding me back here is that I simply don’t know what this form factor is called. Thanks in advance! John PS - My plan, once I get a hat design that works, is to make a mess of these PCBs and mail them out to everyone on this list that wants one for the cost of shipping.

The RCB-F9T is definitely something *not* to emulate -- it uses an SMB connector for the antenna (which no one else does) and it only has a 10 pin header (on 2mm, not 2.54mm spacing) that provides only one TIMEPULSE output and no EXTINT inputs. Why u-blox decided that was a good form factor is beyond me. You might take a look at the Sparkfun carrier boards. They seem well thought out. I've also done a ZED-F9T/P carrier board that I'd be happy to share designs for; it's the opposite of the RCB in that it makes *everything* accessible. I'll try to get the design files on my github (github.orb/n8ur) later today. Note that the ZED-F9 chips have multiple ground pads under the chip and can't be hand soldered; you'd need to use an oven. John ---- On 6/3/21 11:09 AM, John Miller via time-nuts wrote: > Hello Everyone! > I am interested in designing a Pi hat PCB to be compatible with a timing GPS PCB design that I have seen used in a number of places. I have found an “okay” digram, but if anyone has already made gerbers for this thing, I would greatly appreciate it. > > - Diagram: https://files.millerjs.org/misc/timing_board_PCB.jpg <https://files.millerjs.org/misc/timing_board_PCB.jpg> > - LEA-M8T using this format: https://files.millerjs.org/misc/LEA_M8T.png <https://files.millerjs.org/misc/LEA_M8T.png> > - Trimble Resolution T: https://files.millerjs.org/misc/trimble_resolution_t.png <https://files.millerjs.org/misc/trimble_resolution_t.png> > > Even the relatively new uBlox RCB-F9T uses it, calling it an “industry standard form factor” : https://www.u-blox.com/en/product/rcb-f9t-timing-board <https://www.u-blox.com/en/product/rcb-f9t-timing-board> > > In the RCB-F9T documentation they have a very nice diagram of the module that surely came out of something like Altium, but I can’t find any files to replicate it - https://files.millerjs.org/misc/RCB_F9T.png <https://files.millerjs.org/misc/RCB_F9T.png> > > Any help would be greatly appreciated, I think one of the biggest things holding me back here is that I simply don’t know what this form factor is called. > > Thanks in advance! > > John > > PS - My plan, once I get a hat design that works, is to make a mess of these PCBs and mail them out to everyone on this list that wants one for the cost of shipping. > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-leave@lists.febo.com > To unsubscribe, go to and follow the instructions there. >

Hi John, I appreciate the feedback - I didn’t mean to imply that I wanted to build these to use an RCB-F9T on, rather I wanted to play with other receivers that do use the same footprint. These are devices I already have, and want to cleanly integrate with a Pi. Thanks, John > On Jun 3, 2021, at 11:38 AM, John Ackermann N8UR <jra@febo.com> wrote: > > The RCB-F9T is definitely something *not* to emulate -- it uses an SMB connector for the antenna (which no one else does) and it only has a 10 pin header (on 2mm, not 2.54mm spacing) that provides only one TIMEPULSE output and no EXTINT inputs. Why u-blox decided that was a good form factor is beyond me. > > You might take a look at the Sparkfun carrier boards. They seem well thought out. > > I've also done a ZED-F9T/P carrier board that I'd be happy to share designs for; it's the opposite of the RCB in that it makes *everything* accessible. I'll try to get the design files on my github (github.orb/n8ur) later today. > > Note that the ZED-F9 chips have multiple ground pads under the chip and can't be hand soldered; you'd need to use an oven. > > John > ---- > > On 6/3/21 11:09 AM, John Miller via time-nuts wrote: >> Hello Everyone! >> I am interested in designing a Pi hat PCB to be compatible with a timing GPS PCB design that I have seen used in a number of places. I have found an “okay” digram, but if anyone has already made gerbers for this thing, I would greatly appreciate it. >> - Diagram: https://files.millerjs.org/misc/timing_board_PCB.jpg <https://files.millerjs.org/misc/timing_board_PCB.jpg> >> - LEA-M8T using this format: https://files.millerjs.org/misc/LEA_M8T.png <https://files.millerjs.org/misc/LEA_M8T.png> >> - Trimble Resolution T: https://files.millerjs.org/misc/trimble_resolution_t.png <https://files.millerjs.org/misc/trimble_resolution_t.png> >> Even the relatively new uBlox RCB-F9T uses it, calling it an “industry standard form factor” : https://www.u-blox.com/en/product/rcb-f9t-timing-board <https://www.u-blox.com/en/product/rcb-f9t-timing-board> >> In the RCB-F9T documentation they have a very nice diagram of the module that surely came out of something like Altium, but I can’t find any files to replicate it - https://files.millerjs.org/misc/RCB_F9T.png <https://files.millerjs.org/misc/RCB_F9T.png> >> Any help would be greatly appreciated, I think one of the biggest things holding me back here is that I simply don’t know what this form factor is called. >> Thanks in advance! >> John >> PS - My plan, once I get a hat design that works, is to make a mess of these PCBs and mail them out to everyone on this list that wants one for the cost of shipping. >> _______________________________________________ >> time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-leave@lists.febo.com >> To unsubscribe, go to and follow the instructions there. > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-leave@lists.febo.com > To unsubscribe, go to and follow the instructions there.

In that case, it seems the best option is to mount the module on standoffs to your Pi hat board, so you really only need dimensions for the mounting holes, and that first diagram has them. For confirmation, the RCB-F9T datasheet shows the same dimensions. Use a 2x4 2mm pin header and a ribbon cable to connect the two boards. If you want a CAD file for sketching everything up, there's a STEP model of the RCB-F9T on Github: https://github.com/u-blox/3D-Step-Models-Library/blob/master/POS/RCB-F9T(AP214).STEP I agree the only reason to use this form factor is if you can get surplus modules for cheap, which they are. With that form factor you also lose breakouts for all the other interfaces to the u-blox module -  no I2C, SPI, or USB. I believe you can still send UBX messages over UART though. On 6/3/2021 10:16, John Miller via time-nuts wrote: > Hi John, > I appreciate the feedback - I didn’t mean to imply that I wanted to build these to use an RCB-F9T on, rather I wanted to play with other receivers that do use the same footprint. These are devices I already have, and want to cleanly integrate with a Pi. > > Thanks, > John > >> On Jun 3, 2021, at 11:38 AM, John Ackermann N8UR <jra@febo.com> wrote: >> >> The RCB-F9T is definitely something *not* to emulate -- it uses an SMB connector for the antenna (which no one else does) and it only has a 10 pin header (on 2mm, not 2.54mm spacing) that provides only one TIMEPULSE output and no EXTINT inputs. Why u-blox decided that was a good form factor is beyond me. >> >> You might take a look at the Sparkfun carrier boards. They seem well thought out. >> >> I've also done a ZED-F9T/P carrier board that I'd be happy to share designs for; it's the opposite of the RCB in that it makes *everything* accessible. I'll try to get the design files on my github (github.orb/n8ur) later today. >> >> Note that the ZED-F9 chips have multiple ground pads under the chip and can't be hand soldered; you'd need to use an oven. >> >> John >> ---- >> >> On 6/3/21 11:09 AM, John Miller via time-nuts wrote: >>> Hello Everyone! >>> I am interested in designing a Pi hat PCB to be compatible with a timing GPS PCB design that I have seen used in a number of places. I have found an “okay” digram, but if anyone has already made gerbers for this thing, I would greatly appreciate it. >>> - Diagram: https://files.millerjs.org/misc/timing_board_PCB.jpg <https://files.millerjs.org/misc/timing_board_PCB.jpg> >>> - LEA-M8T using this format: https://files.millerjs.org/misc/LEA_M8T.png <https://files.millerjs.org/misc/LEA_M8T.png> >>> - Trimble Resolution T: https://files.millerjs.org/misc/trimble_resolution_t.png <https://files.millerjs.org/misc/trimble_resolution_t.png> >>> Even the relatively new uBlox RCB-F9T uses it, calling it an “industry standard form factor” : https://www.u-blox.com/en/product/rcb-f9t-timing-board <https://www.u-blox.com/en/product/rcb-f9t-timing-board> >>> In the RCB-F9T documentation they have a very nice diagram of the module that surely came out of something like Altium, but I can’t find any files to replicate it - https://files.millerjs.org/misc/RCB_F9T.png <https://files.millerjs.org/misc/RCB_F9T.png> >>> Any help would be greatly appreciated, I think one of the biggest things holding me back here is that I simply don’t know what this form factor is called. >>> Thanks in advance! >>> John >>> PS - My plan, once I get a hat design that works, is to make a mess of these PCBs and mail them out to everyone on this list that wants one for the cost of shipping. >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-leave@lists.febo.com >>> To unsubscribe, go to and follow the instructions there. >> _______________________________________________ >> time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-leave@lists.febo.com >> To unsubscribe, go to and follow the instructions there. > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-leave@lists.febo.com > To unsubscribe, go to and follow the instructions there.