MakerFocus GT-U7 GPS Module Satellite Navigation Positioning GPS Receiver Drone Microcontroller Compatible with NEO-6M 51 Microcontroller STM32 Arduino UNO R3 with IPEX Antenna High Sensitivity

I'm using these modules to get accurate time for a Raspberry Pi based clock. For a first test I simply connected one of the modules (the package contains two of them) using a micro-USB cable to a Linux laptop and confirmed that it was working properly.It took a little longer to setup the Raspberry Pi to enable a serial port on GPIO pins 14 & 15 as well as a PPS input on GPIO pin 18. After disconnecting the USB cable and using test leads with mini-clips, I connected the GPS module to the GPIO pins (as well as power) on the Raspberry Pi (I used a Pi 3B this time, but any model should work). Using gpsd I confirmed that I got time and position data from the module as well as the PPS ticks for extra clock precision.The sensitivity of the module is sufficient to get good data from several satellites anywhere within the house (I tried a number of locations to confirm the clock would work there).Unlike GPS modules that I have used in the past (like SiRF-III), these modules have an external antenna (included). Attaching the antenna to the module is a little fiddly (due to the small size of the connector) but the advantage is of course that the antenna can be placed outside of any project case that may otherwise block the reception.The GPS module has a sticker identifying it as a Goouuu GT-U7 but the software recognized it as a uBlox compatible module (given the low price it is either a uBlox product from an older generation or a 3rd-party clone). I did not do any testing regarding location accuracy or the speed of obtaining a 3D-fix since those are not relevant for my purpose.I'll keep the 2nd module for a future project.I'm perfectly happy with this purchase.

Overall; Recommended.Purchased to add GPS to a Heltec V3 LoRa device running Meshtastic. Hookup instructions can be found on the Meshtastic website and several other locations (Amazon Terms of Use prohibit providing the links, use your fav search engine to find them). Remember to redefine the GPIO pins for RXD (GPS_RX_PIN 45) and TXD (GPS_TX_PIN 46) signals. I didn't bother with the GPS_Enable pin for now, manually disconnecting the VCC header (may add a switch or the switching transistor mod described on the Meshtasitc site later).Pinout on the GPS board is slightly different than the examples I found, but the labeling is correct. I used the headers provided with the Heltec and with the GPS and a set of breadboard jumpers I already had for wiring, this simplifies disconnecting the GPS if not needed. The headers complicate packaging if you want to use one of the case designs on 3D printing sites or available for purchase. Of course, you can solder direct-wire for a less bulky assembly.The antenna is separate and comes with an IPEX connector to attach to the GPS board. The antenna can be mounted to maximize GPS signal reception while the GPS receiver can be mounted forGPS performance is good, and it picks up signals inside my house better than a USB-based GPS I use for 2M VHF AFSK APRS. The additional power consumption is not bad, a few days of tests suggests I can get a bit over 24 hours of operation with a 3000 mAH battery. The Heltec V3 is not ultra low power consumption, so I would expect much longer operation with a less power-hungry LoRa device.

My application is timekeeping, and certainly does not involve flight control.This module was intriguing given its low price relative to other modules.Notes:• MicroUSB connector makes it super quick to check operation against a 9600 baud serial port/terminal.• Operates on 5V, and I’ve confirmed on a scope (and by use) that both the TXD and PPS output TTL levels.• Draws ~35ma @ 5V.• PPS is a positive-going 100ms pulse and it appears that the positive transitions mark the *next* received sentences, and seconds=00. Note that PPSs only appear when there’s an actual fix (eg. $GPRMC Status term = ‘A’) The little red LED on the breakout board seems to be wired as inverse-PPS, so solid red until a fix, then pulsing off in tandem with PPS. Useful.• I confirmed that two otherwise unrelated modules with fixes, do PPS exactly in tandem, as expected.• Sentences output (at 1s intervals of 9600 baud) are ($GP)RMC, VTG, GGA, GSA, GSV & GLL. I only needed RMC & GGA.• Position output was spot-on at least when static on my desk. Had no need to evaluate it in motion.• Sentences seem to work fine with the usual GPS parsing libraries, or if you roll your own.• The breakout module features what appears to be a small rechargeable coin cell spot-welded to its holder, permitting hot-starts.• The supplied patch antenna on a short pigtail with a U.FL connector works well. So does a more substantial GPS antenna terminated with a U.FL. Keep in mind U.FL connectors are not intended for repeated mating cycles. ie, they’re fragile! Use a magnifying glass when connecting.What I find questionable:• Vendors’ Amazon description claims to be “using the original UBLOX (sic) 7th generation chip”. Obviously, the “GT-U7” module on this breakout board does not claim to be a u-blox product. Is it then using some sort of “original” ublox chip inside it? Reading up on how to spot a fake on ublox’s site leads one to believe this is in fact some sort of clone of the u-blox Neo 6 or 7. Startup $GPTXT sentence claims itself as u-blox 7, tho… Questionable if module is in fact configurable via u-center, although u-center has no problem parsing its output. If you are expecting something genuine-ublox, do some research.• Questionable how 5V-tolerant RXD, the sole input on this breakout, might be. Since I do not plan on sending it any configuration, I’m leaving it disconnected and using the module in its default mode.• A schematic of this breakout board would be very useful, in particular to answer the previous question. Can’t seem to find one for it. Aargh. Easy enough to reverse-engineer, given motivation to do so.So, would I trust this product in my 1/8 scale autonomous jet-powered RC A380 model aircraft? Probably not.But for my timekeeping application, it works fine, thus not subtracting any stars since I’m realistic about its pedigree.---