We use the board but my boards are presently in Connecticut so I can not check. Pin 18 of the Ublox is used to feed power to an active antenna that is why the Rf pin does not have a capacitor. I have fed 5V in to pin 18 on ny Saw Tooth boards. Some one check if pin 8 in question is connected to pin 18, may have a resistor in series to prevent to much current. May also measure against the center pin of the SMA Hardwarre manual limits the Voltage to 6V. Bert Kehren In a message dated 1/10/2021 6:02:50 AM Eastern Standard Time, time-n...@welwarsky.de writes: On Samstag, 9. Januar 2021 23:38:35 CET Nigel gm8pzr via time-nuts wrote: > I've dealt with this seller before, always been very happy with the results, > and agreed a price on three such modules which arrived just before > Christmas, for reference this particular Ebay ID was 333619130232, and > finally found time to start checking them today. The modules themselves > look very nice, but one of the auction photos is a connection diagram that > shows Pin 2 of the 8 pin interface connector as "Power In 5V DC", and on > this PCB that pin connects directly to the pin 6 Vcc input on the Ublox > module, which has an absolute maximum rating of 3.6V .......whoops! This is > not intended in any way to be a criticism of this seller, who I am more > than happy to recommend, nor indeed of any other seller, but this is a > generic diagram that several sellers are using for various Huawei/Ublox > modules, some of which may have an onboard 3.3V regulator, as presumably > did the one this diagram originally referenced, but some of which may not.
On a cursory look at the PCB, there are more odd details about it. The antenna circuitry and especially the bias-t looks wrong. The connection diagram lists a 5V pin for an antenna voltage supply and there seems to be a dedicated circuit for short/open circuit detection, but there's no DC blocking cap in the antenna feed line. I'm starting to believe that this board was not originally designed for a LEA- M8 at all. In fact it was probably made for a LEA-6T, the open/short antenna detection looks a bit like the circuit shown in figure 47 in the LEA-6 HIM. Also, the LEA-6 modules have an internal DC block in the antenna input so you would not need an external one. Regards, Matthias _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
