I don't have a TDC650 to try on, but I tried battery changes on TDC600 v1 and TDC600 v2 (one of these is the Android device at the core of the TDC650). Both of those reset their date and time even if you do a battery swap with 15 seconds between removal of old battery and insertion of new battery (TDC600 v1 to 1 Jan 2019, TDC60 v2 to 21 Jan 2024). Both of them recover quickly if you have a WiFi connection, but I understand that this isn't available.
I haven't worked with the strap-on GNSS used on the TDC650, other GNSS receivers I've worked with have struggled to give positions when they have the wrong Date & Time so this is probably the root cause of your problem.
Connecting an external battery pack while doing a battery change as suggested by Eric Bock keeps date and time on a TDC600, even with an extended 1-minute battery change, so that's probably the easiest solution. I used a small Anker PowerCore+ Mini 3350mAH, I guess most external USB battery packs would work.
Setting the date and time manually after changing the battery (as suggested by Carson Garver) may help, but I don't have a TDC650 to try that method on.
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Norman Smart
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Original Message:
Sent: 03-05-2024 19:23
From: Sam Bombara
Subject: TDC650 loses connection after swapping battery
Hi all,
We are having a connectivity issue with our TDC650 unit that is occurring while we are in the field. We generally work long field days (10+ hours in summer) and need to swap out the battery with a second one while in the field, generally in the afternoon. We are running into a problem where the TDC650 will not provide a location after the battery has been swapped. The unit will connect to 20+ satellites but will not provide a horizontal or vertical position and will not let us record a location. Trimble Mobile Manager will also not connect.
Our TDC650 does not have cellular service. The problem seems to resolve when the unit is brought back inside, connected to WiFi, and synced. However this is not possible in remote places when working long field days. Is it possible a setting is changing when the battery is being swapped? I surely hope an internet connection is not required after a battery swap as that renders this unit almost complete useless to us in summer...
Thanks!
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Sam Bombara
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