BCD436HP/BCD536HP: RTC Batt Location?

[kruser]

Where exactly is the RTC battery in the 436HP?

Is it under a soldered shield and on which board.

I'm also seeing conflicting info regarding the charging of the RTC cell.

UPMAN says the 436HP must be on but another post says the RTC cell will charge regardless if the 436 is on or off as long as it is plugged into USB power.

Mine does seem to charge with the 436 off as it would ask me for the time each time I turned it on without USB power.
After supplying USB power but leaving the radio off, it is holding time.
So it appears the RTC cell is charging regardless if the 436 is on or off.
Possibly something in a firmware change I missed as I don't use my 436 often and had not updated the FW since 1.03 something!

Anyway, if anyone has any insight if the 436 now charges the 436 RTC cell if the radio is on or off would be great.
Also if anyone can give specifics as to the cells location inside the 436 would also be helpful.

I modded my 536 with an ML2032 rechargeable lithium cell and have not had any RTC issues with it but I know a ML2016 or ML2032 will not fit into a 436.

Thanks All

 

[Voyager]

I'm 99% certain it will only charge when the unit is powered on.

Otherwise, the initial instructions would be to just connect USB power for 50 hours. It is not - it specifies that the unit must be on for that long. The USB provides the only source capable of keeping the unit on that long.

Why not just let Uniden replace it, and hopefully never have that issue again.

 

[kruser]

I'm 99% certain it will only charge when the unit is powered on.

Otherwise, the initial instructions would be to just connect USB power for 50 hours. It is not - it specifies that the unit must be on for that long. The USB provides the only source capable of keeping the unit on that long.

Why not just let Uniden replace it, and hopefully never have that issue again.

That's what I was thinking is that it does charge the RTC cell but only when it is also charging the NiMH cells. Once that timer expires, the RTC cell may also stop charging until the unit is turned on.
That's the only explanation I can come up with as to why my RTC cell appears to be charging with the unit off.

As far as replacing it, mine has not failed. Perhaps because I don't use it much at all.
I imagine by the time it does fail, the unit may be out of warranty hence the reason for asking for the location of the cell in the 436.

I did find a thread with a picture and you even asked the OP if the pic was from a 436 but he never answered.
I could not really tell from the pic as I don't recall the inside look of my 536. The pic did almost look like a shield cover had been removed to expose the cell though as the solder in the pic was kind of sloppy looking perhaps from an iron with not quite enough watts to overcome the metal shield.
I do know the 536 RTC cell is not under a shield and mine sure did not have the look that a shield had been removed.

I also looked at board marking and could not see one for the RTC. I was hoping I could and I could have measured that point with the 436 on and off.
I do think you are correct though that in order to get the full 50 hour charge, the unit must be on. Or you could melt it down by replugging the USB cable to start a new charge timer cycle!! That's if it does charge the RTC cell when also charging the NiMH cells which mine appears to do.

Mine sits at work mostly plugged into USB power but off and of course the charging circuit has also timed out or I told it no when connecting.
I don't know if it has a default after a power failure but I set my charge time to 1 hour just in case it does auto charge after a power failure.

I turn it on just enough that I rarely see the Set Time prompt but did see it today after I'd not used it for darn near a month. In this case, it was also not plugged into USB power for a month or so.