Hello, I am new to this, so advice is welcome. I had a Trimble thunderbolt running the whole summer and when checking today, it seems I lost satellite tracking. But I don't know what is wrong or how to diagnose it. I tried a power cycle and factory reset. In the thunderbolt monitor 1. all alarms are green. 2. signal levels (SV and AMU) are all empty with a question mark. 3. I seem to get an accurate time. 4. the timing outputs seem be ok and quite stable, nothing compared to a first start. 5. I get a GPS position. 6. RCVR mode = (7) Overdet. Clock (time) 7. GPS status = (0) Doing fixes It seems the time is getting in, but no satellite fixes. I checked the bias of the antenna, it was about 5 volts. What could be wrong? Or how could I check it further? The GPS antenna is about 5 meters from the house but only about 50cm from the ground. Could this be seasonal? Is my house blocking the signal this time of year? I added some screenshots on the EEVBlog forum: https://www.eevblog.com/forum/metrology/trimble-thunderbolt-nu-satellites-12 8752/new/#new I'm a bit lost to be frank. Thank you.

On 2020-12-03 01:51, jan.catrysse@gmail.com wrote: > I had a Trimble thunderbolt running the whole summer and when checking > today, it seems I lost satellite tracking. It is worth trying a different antenna. The lack of antenna alarm in the monitor program indicates that the amplifier in the antenna has not failed completely, at least not in a way that causes it to stop drawing current, or draw too much current, but lack of satellites tracked would seem to indicate something in the front end RF chain. Antenna is the easiest to check. If not the antenna then possibly the front end RF amplifier was damaged, but I've never looked into how difficult that would be to change. Hopefully just a damaged antenna from a summer thunderstorm or similar. -- Chris Caudle