John I suspect we may be the only ones interested in these units. Can we connect offline? I am at paulsw...@gmail.com.
With respect to Murphey Surplus they have been around for 30+ years. I think if you reach out to them they will take care of the issue of wrong/bad units. I have one damaged top connector. No real need to fix that. USB you need a USB driver to use it. Will reach out to Ublox to see if a 32/64 bit may be available. With respect to wire on the next unit for TX1/RX1 plan to use 34 gauge wire nice and flexible. This particular stuff is supposed to be solderable. Will see. Regards Paul Regards Paul On Wed, Apr 6, 2022 at 7:08 PM paul swed <paulsw...@gmail.com> wrote: > John your pins are correct. I am thinking about 3 and 1 for ttl rs 232 > from tx1/rx1. > Though I really need to try usb, maybe no need to screw with tacking wires > on. > I have found the chip by the top connector. Its a L-band switch. Doesn't > make sense but what can I say. Also removed the 3.5V glob board this > afternoon. > As far as the connector goes I acquired connectors and cables at hamfests > years ago. > So that made it easy. > Regards > Paul > > > > On Wed, Apr 6, 2022 at 6:15 PM John Miller via time-nuts < > time-nuts@lists.febo.com> wrote: > >> Paul, >> Thanks again for the addition info - very helpful. Mine came in this >> afternoon >> and unfortunately only three of them are LEA-4Ts, the other two are >> Leadtek >> LR9548S SiRF StarIII based modules, one of which has a sticker that reads >> "short" on it. I could request a partial refund but the seller probably >> just had >> no idea. >> >> From my own continuity testing (I haven't powered them up yet) I have >> determined the following pinout. With the boards in "vertical" >> orientation, >> pin 1 is the leftmost pin. It's also the square pin on the footprint. >> >> 1 - NC >> 2 - Vcc/VDDUSB (3v) >> 3 - NC or 3v for LNA power if sub-board is present >> 4 - USB DM >> 5 - USB DP >> 6 - PPS >> 7 - GND >> 8 - NC >> >> My next step is to find my 30AWG wire-wrap wire and tack wires straight to >> the module, then figure out how to get an antenna connected. I don't >> think I >> have any adapters this small. >> >> John >> >> >> >> >> > On Apr 6, 2022, at 1:09 PM, paul swed <paulsw...@gmail.com> wrote: >> > >> > John indeed on the 3V. I have lots of 3.3V regs. Not sure I have a 3. >> But >> > like you I am thinking the same only maybe simpler. Simply solder it to >> a >> > piece of copper board thats larger so I can mount interface chips drill >> > holes for screws and such. Also some standoffs for 1pps, ext in/out, >> rs232 >> > tx1/rx1. Smaller wires are the way to go on connecting to the pins. At >> 3V >> > startup is 65ma settles to 57ma. The input is a bit odd. Like you I >> spotted >> > the mcl combiner/splitter. The side port is 4-5 db hotter than the top >> > port. But both work. So its a bit odd as if it was intended for 2 >> antennas. >> > Kind of doesn't really matter as its totally working on the TX1/RX1 >> port. I >> > set it to 115200 baud. It comes up 9600. That change is sort of silly. >> > Thinking about mounting the board on the copper board component side >> down. >> > Easy to solder copper support wires then. No screw holes kind of a pain. >> > While soldering I have a small tip iron and found it really needs to be >> at >> > 700 F or so to do good job. >> > On one of my units and in the ebay pix there is a spot of tape that >> holds >> > down I assume a small regulator and TCXO. But it really doesn't seem to >> do >> > anything. Four of my units do not have that mod. So have not really >> figured >> > it out yet. >> > Good luck. >> > Paul >> > >> > On Wed, Apr 6, 2022 at 12:51 PM John Miller via time-nuts < >> > time-nuts@lists.febo.com> wrote: >> > >> >> Hi Paul, >> >> Thanks for sharing this info! I ordered one of these lots as well, and >> it >> >> should arrive today, actually. My intention is to re-mount the modules >> on >> >> more sensible breakout boards, maybe a Pi Hat. >> >> >> >> The 8 pin chip on the board is an MCL BP2G. RF power combiner/splitter >> >> https://www.minicircuits.com/pdfs/BP2G+.pdf < >> >> https://www.minicircuits.com/pdfs/BP2G+.pdf> >> >> >> >> If I am reading the datasheet and board layout right, the top >> connector is >> >> connected to PORT1, the GPS is PORT2, and the side connector is SUM. I >> >> would imagine that the GPS would be on SUM if the idea was to feed in >> >1 RF >> >> signal, but maybe I am misunderstanding it? >> >> >> >> I was surprised by your note that the USB voltage input is 3v, but >> after >> >> checking the LEA-4x datasheet, sure enough, 3.6v max. I thought all >> USB had >> >> to be 5v? >> >> >> >> Finally, it looks like the PCB is ceramic, rather than normal >> >> epoxy/fiberglass. Hopefully that doesn't make removing the modules any >> more >> >> difficult... >> >> >> >> John >> >> >> >>> On Apr 5, 2022, at 9:14 PM, paul swed <paulsw...@gmail.com> wrote: >> >>> >> >>> Hello to the group. >> >>> Gregory had mentioned a deal on Ebay for 5 X LEA-4T receivers at $25. >> >>> Seemed like an OK deal to be able to have a few units around for >> >>> experimenting. >> >>> They arrived and were easy to get operational. >> >>> They are a little different. The module actually has 2 antenna inputs. >> >> Took >> >>> a bit to figure out what was going on. Both work in the L1 band and >> the >> >>> side connector appears more sensitive by 4-5 db. But both work. >> >>> Its a circa 2006 16 channel receiver and does capture WAAS. >> >>> Locks in about 30 second from cold start. Ublox u-center 8.18 works >> fine >> >>> with the unit. >> >>> Its setup for USB. But that USB is just 3V logic so be careful. >> >>> The unit runs on 3V. None of the ttl 3V rs 232 ports connect to >> anything. >> >>> But TX1/RX1 actually have control and data at 9600 baud. Pins 3-4 on >> the >> >>> actual chip. Attaching some small wires allowed complete control of >> the >> >>> module after passing through a logic to usb serial converter. >> >>> 1 PPS works just fine but have not compared it to anything. >> >>> So for me at least the $5 wonders will be fine. >> >>> Regards >> >>> Paul >> >>> WB8TSL >> >>> _______________________________________________ >> >>> time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe >> >> send an email to time-nuts-le...@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-le...@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-le...@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-le...@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-le...@lists.febo.com To unsubscribe, go to and follow the instructions there.