Bob I'm with you on jlcpcb -- I actually have two different designs with 10 of each, with components installed winging their way to me at the moment for a grand total of $85 including shipping. Yes, not complicated boards, but still fun to design and get built. One of them is of vague interest to this group as it is a pendulum timer to monitor pendulum swings and generate log of the clock performance. Lots of interesting details come out of the data....
Philip On Wed, Dec 9, 2020 at 6:03 PM Bob kb8tq <[email protected]> wrote: > Hi > > What you want around the uBlox depends a lot on what you are trying to do. > > These days, putting an MCU directly on this or that is a pretty cheap > option. > (very much so if you are using JLPCB). > > Do you isolate / buffer this or that? Full RS-232 I/O adds a chip and a > few parts. > > Do you regulate this and that on the board? Is the antenna supply > independent of > the module? Do you have full sensing on the antenna supply? > > For some, part of the mix is a delay chip to handle the sawtooth > correction. Very > much a “that depends” sort of thing. > > Do you put a counter / TDC of some sort on the board to do a compare to an > external > PPS? (At this point this list just about has a full GPSDO buried in it ….) > > Lots of choices and lots of directions you could go. > > One of the reasons I really like JLPCB is that you can do up 5 of a board > like this, > with a lot of parts populated and still not have spent $100 (delivered > ….). As long > as you have confidence in the footprints, the risk is pretty small. > > One note: JLPCB is the only “fab + assembly” outfit I’ve tried. Their > boards are > no better / no worse than a lot of other board fab outfits. I have no idea > how they > compare to other assembly houses. My selection criteria: “ are they the > cheapest > I can find?” :) > > Bob > > > On Dec 9, 2020, at 5:35 PM, Matthias Welwarsky <[email protected]> > wrote: > > > > On Mittwoch, 9. Dezember 2020 21:46:25 CET Philip Gladstone wrote: > >> I have used the assembly service from jlcpcb a few times for small runs > -- > >> it is absurdly cheap *if* you are using common surface mount components > and > >> cheap for the less common ones. I then hand solder the connectors on > when I > >> get the boards. > > > > That's what I typically do as well. But you don't need a lot of support > > components for a M8T, it's almost not worth it. Effectively, you have > > > > 3 parts for the antenna power feed-in > > 1 decoupling cap for the module itself > > 1 resistor or ferrite bead for each signal you need to break out > > 3(4) parts for the power supply (LDO) > > > > USB needs just a few more parts, two resistors, a protection chip and a > > receptacle. > > > > > >> > >> Philip > >> > >> On Wed, Dec 9, 2020 at 3:27 PM Matthias Welwarsky < > [email protected]> > >> > >> wrote: > >>> On Mittwoch, 9. Dezember 2020 14:57:55 CET Bob kb8tq wrote: > >>>> Hi > >>>> > >>>> I think the key point is: > >>>> > >>>> *IF* somebody wants to do a layout using the M8T, Bert already *has* a > >>>> “known good” PCB layout footprint in his inventory of useful stuff. > >>>> Since > >>>> the uBlox is a really odd part, you aren’t going to find that > footprint > >>>> built into the standard layout programs. > >>> > >>> I have a known-good footprint and symbol for KiCAD, if anyone is > >>> interested. I > >>> also have KiCAD project for a small breakout board. It's not too > >>> featureful, > >>> no antenna power switching or monitoring, no support for antenna power > >>> other > >>> than from the built-in LDO. However, it has been successfully used in a > >>> GPSDO > >>> project. All components are hobbyist-friendly 0805, except for a LDO > with > >>> SOT-23-5 footprint. > >>> > >>>> Bob > >>>> > >>>>> On Dec 8, 2020, at 6:26 PM, Bill Notfaded <[email protected]> > wrote: > >>>>> > >>>>> That's a really old board though. An 8 series isn't pin compatible > >>> > >>> with > >>> > >>>>> say LEA-6T is it? The picture had a 5 series in it. > >>>>> > >>>>> Could you use something like this? > >>> > >>> > https://github.com/PaulZC/NEO-M8T_GNSS_FeatherWing/blob/master/LEARN.md > >>> > >>>>> Bill > >>>>> > >>>>> On Tue, Dec 8, 2020, 10:30 AM Gregory Beat via time-nuts < > >>>>> > >>>>> [email protected]> wrote: > >>>>>> There are various Breakout (bare) Boards for the uBlox modules > posted > >>> > >>> on > >>> > >>>>>> Internet. > >>>>>> SparkFun has carried them, in the past, and sometimes sold the bare > >>>>>> boards > >>>>>> without the uBlox module. > >>>>>> https://www.sparkfun.com/products/15005 > >>>>>> > >>>>>> StuartsProjects (Stuart Robinson, Cardiff, UK) has a bare board for > >>> > >>> the > >>> > >>>>>> Ublox MAX M8Q module. Sold on Tindie, used in high-altitude balloon > >>>>>> projects. > >>> > >>> > https://www.tindie.com/products/stuartsprojects/ublox-max-8mq-gps-breakou > >>> > >>>>>> t-board-x-2/ > >>>>>> > >>>>>> Contact Limor “Ladyada” Fried at Adafruit, she might have bare > boards > >>> > >>> OR > >>> > >>>>>> Gerbers for earlier or future products. > >>>>>> https://www.adafruit.com/?q=gps+breakout&p=1&sort=BestMatch > >>>>>> > >>>>>> Dan Watson designed one, for the 6-series five years ago. > >>>>>> He sometimes posted Gerber files. > >>> > >>> > http://syncchannel.blogspot.com/2015/09/a-nearly-perfect-u-blox-gps-break > >>> > >>>>>> out.html > >>>>>> > >>>>>> greg > >>>>>> w9gb > >>>>>> == > >>>>>> Date: Mon, 7 Dec 2020 09:47:55 -0500 > >>>>>> From: paul swed <[email protected]> > >>>>>> To: Discussion of precise time and frequency > >>>>>> > >>>>>> measurement <[email protected]> > >>>>>> > >>>>>> Subject: Re: [time-nuts] Ublox 8T > >>>>>> > >>>>>> Bert Very attractive price. They appear to be on a cut out circuit > >>> > >>> board. > >>> > >>>>>> How are you connecting to them please? > >>>>>> Regards > >>>>>> Paul. > >>>>>> WB8TSL > >>>>>> _______________________________________________ > >>>>>> time-nuts mailing list -- [email protected] > >>>>>> To unsubscribe, go to > >>>>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >>>>>> and follow the instructions there. > >>>>> > >>>>> _______________________________________________ > >>>>> time-nuts mailing list -- [email protected] > >>>>> To unsubscribe, go to > >>>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and > >>>>> follow the instructions there. > >>>> > >>>> _______________________________________________ > >>>> time-nuts mailing list -- [email protected] > >>>> To unsubscribe, go to > >>>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and > >>> > >>> follow > >>> > >>>> the instructions there. > >>> > >>> _______________________________________________ > >>> time-nuts mailing list -- [email protected] > >>> To unsubscribe, go to > >>> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > >>> and follow the instructions there. > >> > >> _______________________________________________ > >> time-nuts mailing list -- [email protected] > >> To unsubscribe, go to > >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and > follow > >> the instructions there. > > > > > > > > > > > > _______________________________________________ > > time-nuts mailing list -- [email protected] > > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
