The photo above shows initial burn-in testing for a Premium Duplex hotspot. We have several test setups like this and can test up to four hotspots at a time. The setup on the left is testing the OLED display before any soldering is done. We use a cheap JumboSpot running Pi-Star for this and have added a special pigtail so we can temporarily hook up the display. We check for brightness, correct polarity, heat buildup, and straightness. This particular OLED is okay except it is not straight and will look bad in a case. To fix this, we have to gently heat the back with a rework station at about 200 degrees. That will soften the glue holding the OLED to the PCB enough to straighten the display. Very few of these are actually perfect out if the package.
The setup on the right is testing an N5BOC Duplex board. These ALWAYS test good. Before we start assembly, we’ll put antennas on this and check the BER and change the RXOFFSET value if necessary. N5BOC boards usually don’t require any change. We can almost always get a .3 to .4 BER straight from the factory. But sometimes a small change will improve the BER slightly. We’re looking for a .2 to .3 average over 10 transmissions. Any offset adjustment is noted and incorporated into the final programming.
This phase of testing runs for at least 8 hours, usually overnight. If anything is going to go wrong, it usually will within that time. If everything looks good, we will assemble the hotspot and test it again for 1-2 hours before it goes to programming.