Uniden 436/536HP clock problems

[kruser]

The RTC in the x36HP scanners appears to be maintained by the main processor chip and a SMD style supercap when the power is switched off.

Supercaps cannot be fast charged, hence the requirement to leave scanner on for 2 days to fully charge.

The x36HP's RX63N/RX631,100Mhz RISC processor RTC, requires a relatively high 0.6 - 1mA to maintain the clock function, so it's not surprising that only 5-7 days of backup are available.

Thanks for that info. I'd just started a new thread asking if the battery was really a super cap but I think your info confirms that it is.
And 0.6 to 1mA is a lot for a simple RTC circuit.

I guess the life of modern day super cap may exceed that of a real battery cell so that fact may have been a good decision but I must agree on the use of such a high current RTC circuit being a bad choice. I have wristwatches that have teeny tiny button cell batteries that even have mechanical movements that can run nearly a year!

Any idea what the "full charge" voltage is at the super cap?

 

[tkenny53]

It would be much better if one could just bypass the clock and date setting when powered up. It is a handheld scanner, you want it to just work on power up and not have to set time and day. Mine sits in the car till I need it, off and only runs on the AA batteries. It is a PITA to have to fiddle with keystrokes just turn and set the time and date, before you need to scan for stuff. This should not be a probrlem to resolve, but not every scanner is perfect, but, here this could have been avoided by a little preplanning in the design phase.

 

[JamesO]

Never had a prompt to set the clock on my 436HP after the initial request.

I usually run the scanner on batteries, and also have it turned off for days at a time if I can carrying another scanner or out of scanning mode.

If anyone keeps getting clock prompts from their x36HP, make sure you keep it powered up and running for at least 3 days straight, then see if you keep getting prompts to set the time.