running Reachview 2.5.3 on this module.
I am having a strange issue where the signal strength shown in Reachview drops by [edit] 5dB after a period. When cold booting the signal drop occurs after ~40 seconds. If the antenna is unplugged and reconnected, the initial signal appears good, but then after around 10 seconds drops right down again.
The drop is enough to reduce 10 green sats to 2 to 4, and the signal seems to gradually deteriorate after then, so after a few minutes only 1 or 2 sats are in the green. I noticed the problem when trying to get good signal on one of my rover units, but it is occurring with the module I have configured as base as well. I have tried a couple of stock tallysman antennae (on copper plated cd ground planes which have worked well in the past), and with a maxtena m1227hct. They all exhibit the same behaviour. I have tried with power via USB and from the Pixhawk 5V pin.
Raw log attached - the antenna was positioned with good view of sky, on a sunny afternoon. The initial dropout occurs around 43 seconds into the log. I then disconnected and reconnected the antenna twice, so the logs should show the signal drop to zero, then recover with plenty of green sats, then around 10 seconds later, the signal strength can be seen dropping back to low levels.
The practical effect, of course, is to make achieving a solid float/fix solution rather unlikely.
I am uploading a (very boring, slightly out of focus) video of the Reachview display, showing the initial good signal following boot, the initial dropout at 42 seconds and then shortly afterwards the effect of unplugging/replugging the antenna:
Any pointers on what could be going on? I had been blaming my setup on the drone in question, but the issue seems independent of drone or other local electronics which could be causing interference.
I should add that I have previously had good results wit all my reach units. It has been a while since using the system for work, so I’m not sure exactly when the problem started occurring.
raw_201707181352.zip (495.4 KB)
edited - it’s more like a 5dB signal drop