QRP LABS QLG2

I was most fortunate to obtain one the the very first batches of the excellent QLG2 GPS unit from QRP Labs. I built mine into one of the custom enclosures that QRP Labs sells. You can purchase a standard U3S case but with custom front and rear panels.

I did a small amount of modification to the panel holes and used a BNC connector for the data / locator, and time outputs as well as a phono connector for the 1 pps output, as used for frequency calibration by the U3S and other models. I added my own LCD panel to monitor data. Two holes on the front panel where unused so I blanked them off with blanking grommets. (Later changed to include LED's for the 1PPS output and DC volts input indicator.) Sensitivity is superb, the best I've seen and I can often see 17 satellites. I did experience a little trouble when using a poor PSU (a wall wart for charging an old drill), but I just used a 3u3 smoothing cap in front of an LM317 regulator to give me the 5v required and it worked. (The GPS module must NEVER have more than 5v applied to it.) A lack of smoothing on the PSU will stop you from getting past the splash screen. (Hints on smoothing capacitor values can be found here). The GPS takes a maximum of 50ma. Warning !!!! Always put a series protection diode before the input to any regulator. If you reverse the supply then you still end up with high voltage output and a broken GPS. You have been warned.

The GPS with regard to using locator and time data is compatible with all QRSS rigs from the U3 firmware above v3.06, the U3S models and all the other QRP Labs kits. The old U2's not supported but could be in the future if QRP Labs issue a firmware update for the GPS. See notes here https://sites.google.com/view/andy-g0ftd/qrss-rigs Updates are simple. Plug the GPS into a USB socket on your PC, any OS. The GPS will appear as a new drive. Use the file manager on your PC to simply over write the old firmware with the new firmware. No need to delete the old one, it auto-magically over-writes. Power down the GPS. Disconnect and then reboot the GPS. Voila !

On my first attempt at adding a simple 5v DC regulator PCB I managed to have a "drilling mishap" and ruin one section of the enclosure. It's hard trying to get the four holes precise without a template and I learnt my lesson that day. I ended up purchasing another enclosure but this time I simply put the small PCB in a sleeve of shrink wrap. No more holes to drill and safe. You can stick it down with a bit of glue to the enclosure if you want.

This is a great tinkerers GPS. By default it's a plug and play operation when used in conjunction with other QRP Labs kits. The receiver can be programmed to use at any one time two of the four GPS constellations, from the original US based GPS, the Russian Glonass system, Chinese Baidu and the European Galileo. Note that you cannot have all at the same time, but any two as I understand it. Default is US GPS and Baidu to increase the time to fix to get a QRP Labs kit running as fast as possible. Time and location from the US GPS have priority over constellations.

Useful links:

Data sheets here - https://drive.google.com/drive/folders/1FQKS9ogv43lJLIl0jdnJnOj9u76tPkkf

Other notes - https://sites.google.com/view/andy-g0ftd/qrss-rigs

QLG2 purchases - http://shop.qrp-labs.com/gps/qlg2

Firmware and other info - http://www.qrp-labs.com/qlg2