> Le 13 mars 2015 à 21:33, Pete Stephenson <[email protected]> a écrit : > > Hi all, > > After a few years of using a Garmin GPS 18x LVC for timekeeping, my > budget now allows for some upgrades and I had a small field day on eBay: > I acquired a Trimble Thunderbolt, two Trimble Resolution Ts, and two > Motorola Oncore UT+s (seconds purchased for spares and testing). > > The documentation for the Trimbles is clear, but I had several questions > regarding the Oncores that I was unable to find clear answers to online. > I would be very much obliged if the folks here might be able to help. > > 1. Is it possible to upgrade the firmware on the Oncore UT+? If so, > where can one acquire the latest firmware (3.2, I believe) files and how > would go one about installing it? Is this something WinOncore can do? I > ask because the receivers on eBay are of varying vintage and may not be > fully upgraded. >
The WinOncore12 application has an option to download firmware but I have not been able to find a source of firmware. > Since Motorola exited the GPS business a relatively long time ago, > firmware updates and directions have proven difficult (impossible so > far) for me to find. > > 2. The two Oncores I purchased were not factory-equipped with a > rechargeable battery. The user guide says that one can apply "Externally > applied backup power (< +5V)" to pin #1 in order to maintain data in RAM > in case the main power is interrupted. > > Can one use a common non-rechargeable coin-cell battery like a CR2032 to > provide this backup power, or does it need to be a rechargeable battery? > Will a CR2032 or the Oncore itself be damaged if such a cell is used? > > 3. Tom says at > <http://lists.ntp.org/pipermail/questions/2012-October/034001.html> that > in addition to being an input for external backup power, pin #1 on the > Oncore provides current-limited 5V for battery/supercapacitor charging. > > Is this true for Oncore receivers that were not factory-equipped with a > rechargeable battery? I don’t recall detecting any voltage on that pin. > If true, what is the maximum current that can be > safely supplied by the pin? As above, is it safe to use a > non-rechargeable battery like a CR2032? I have a couple of UT+ receivers which were not equipped with batteries and I used a CR2032 for backup without any issue. They were disconnected sometimes for considerable periods on a number of occasions and the saved data was always accessible on power up. I don’t know how long a battery like that lasts. I have one, powered off, still with the battery in circuit that I pulled in 12/2010. Hmmm. might be worth powering it on to see. > > If pin #1 can supply power and I wanted to charge a supercapacitor from > that pin, would I also need to include a current-limiting resistor to > prevent the Oncore from sourcing too much current? > > I could find nothing in the user guide that says that pin #1 can be used > for charging a battery. > <http://www.synergy-gps.com/images/stories/ShopTalk/9backup_battery_considerations.pdf> > is unclear on whether or not pin #1 can be used for charging batteries, > or if it's safe to use non-rechargeable cells like a CR2032 coin-cell > battery. > 4. The user manual and the battery backup considerations document says > that the Oncore UT+ draws 5-100 uA (15uA typical) from the backup power > source. Is this a constant draw, even when the main 5V power is being > supplied to the unit, or does the unit only draw current from the > battery when the main power is interrupted? Unknown. > > I'd measure it directly, but none of my multimeters are able to > accurately measure microamperes. > > Thank you all for your time and assistance. If any other time-nuts > happen to make it to Bern, Switzerland in the next few years, please let > me know and drinks are on me. > > Cheers! > -Pete > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
