x
This website is using cookies. We use cookies to ensure that we give you the best experience on our website. More info. That's Fine
HPC:Factor Logo 
 
Latest Forum Activity

HP Jornada 420 backup battery

aab Page Icon Posted 2014-08-31 11:11 PM
#
Avatar image of aab
H/PC Elite

Posts:
669
Location:
Canada
Status:
I got an HP Jornada 420 Palm Size PC recently on eBay and it has one of those built in backup batteries (which amazingly they say only has a 1 minute battery life when new and full, I thought only Palm OS devices were built so poorly).

At first it would say the backup battery was dead seconds after being off the charger, with more leaving it on to drain and charging I'm probably now up to 5-10 minutes of it being on before it complains about the backup battery.

Do you think with more draining and charging I'll get rid of this problem? If not does anyone know what sort of battery it is? I'm suspecting it's most likely a capacitor to have only 1 minute of battery life when brand new and fully charged, is it easily replaceable?

Thanks


Edited by aab 2014-08-31 11:14 PM
 Top of the page
Rich Hawley Page Icon Posted 2014-08-31 11:29 PM
#
Avatar image of Rich Hawley
Global Moderator
H/PC Guru

Posts:
7,188
Location:
USA
Status:
That's not exactly correct. The 420 running totally on the backup battery itself will power the unit for less than a minute. However, it is a rechargable lithium ion battery. And when used correctly, that is when used to simply maintain data once the main battery has been depleted, will do so for about 10 days. <-- I was wrong!!!! (EDITED)
 Top of the page
aab Page Icon Posted 2014-09-01 12:05 AM
#
Avatar image of aab
H/PC Elite

Posts:
669
Location:
Canada
Status:
I'm not sure I understand what you mean, what's the difference between "running totally on the backup battery itself" and "used simply to maintain data once the battery has been depleted"?

Are you saying the backup battery, when new, can actually fully power the Jornada 420 for 1 minute of normal use (turning it on, playing sounds, etc)?

In any case do you know what type of backup battery it is and is a replacement easy to find and install?

Thanks

Edit: The word for word message on the 420's screen in the power properties says:

"A good backup battery retains your data for 1 minute when the main battery is removed."

It doesn't sound like it can power the unit for actual use. With virtually all other devices that use CR2032 batteries, I beleive you get 2 weeks of data retention, that's 20160 times longer battery life.

Edit 2: I think what you meant was that the Jornada 420 will reserve 10 days of data retaining power in its main battery by preventing it from turning on when low, but it's the reserved amount in the main battery that's protecting the data for 10 days, not the backup battery, which they clearly state has a 1 minute battery life.


Edited by aab 2014-09-01 12:13 AM
 Top of the page
Rich Hawley Page Icon Posted 2014-09-01 12:59 PM
#
Avatar image of Rich Hawley
Global Moderator
H/PC Guru

Posts:
7,188
Location:
USA
Status:
Not exactly.

If the main battery totally depletes, the backup battery will maintain the memory state for about 10 days in the "power off" position, with the main battery intact.

Turn it on, and it drains super fast. And that is a fully charged backup battery. One that is older and doesn't hold the charge of a new one will go even quicker, hence your one minute of work time before you lose everything.

It is an internal 3V LION coin cell. To change it you have to open up the device, and actually remove the motherboard as it is mounted on the front side of the pcb.
 Top of the page
aab Page Icon Posted 2014-09-01 6:56 PM
#
Avatar image of aab
H/PC Elite

Posts:
669
Location:
Canada
Status:
It is not my testing that showed a 1 minute backup battery life, it is the manual that states the backup battery protects the memory for 1 minute without the main battery, in my 15 year old 420 the backup battery seems to last 1-3 seconds, I was able to pull the main battery out and in for a second or less without losing data, but pulling it out for 2-3 seconds caused complete data loss.

When they say the data is kept for 10 days, that's with the remaining power of the main battery (it prevents the device from turning on even when some battery power remains, it keeps this power in the main battery to protect the memory contents, it's not the backup battery that can protect the memory for 10 days), the manual clearly states that the backup battery protects the memory for 1 minute with the main battery removed.

Any way the good news is the more I charge and discharge it the longer the backup battery stays at "Good", it started staying at good for seconds, it now stays there for around 15 minutes. Hopefully "exercising" the backup battery some more will cause it to keep a better charge.

I'm considering replacing my Casio E-100 that I use for to do lists and reminders with the Jornada 420, but I need to get the backup battery lasting more than a few minutes before Windows keeps throwing low battery warnings every few minutes.

By the way I remember reviews back in 1999 saying how horrible the touch screen worked on the 420 so I had low expectations, but I see nothing wrong with the touch screen at all, it responds perfectly.


Edited by aab 2014-09-01 6:58 PM
 Top of the page
Rich Hawley Page Icon Posted 2014-09-01 7:18 PM
#
Avatar image of Rich Hawley
Global Moderator
H/PC Guru

Posts:
7,188
Location:
USA
Status:
Well, that sucks.

I guess you'd better be all set to put in a new battery if your primary is about dead...only one minute? Crap. The fact that you said you could run your Jornada for a few seconds without a battery present shows that it is old technology.

I mean, most handhelds won't run at all with just the backup battery present...and will keep there data for quite a long period with a good CR2032 cell in place, even without a main battery present.

I had read the manual, page 16 and was reading it incorrectly. What is confusing is the statement on this HP webpage:

http://h20566.www2.hp.com/portal/site/hpsc/template.PAGE/public/kb/...

That's where I got the 10 days from. I remember from my Aero 1500 days, I could let the battery totally deplete and still keep my data for a long time on the backup cell.

Also I hear you about exercising the backup cell...yet I was under the impression that exercising LION did little or not good, unlike NicCad batteries.

I owned all the Casio pocketpcs at one time or another...loved the huge screen on the E100 when it first came out.

I really have no need for a shopping list, because if I forget something, my wife reminds me and sends me back.
 Top of the page
aab Page Icon Posted 2014-09-01 10:33 PM
#
Avatar image of aab
H/PC Elite

Posts:
669
Location:
Canada
Status:
I think we're misunderstnding each other, the main battery lasts a fair while given its age (I didn't expect it to work at all), it never died so far but does get to "very low" after perhaps 15-30 minutes on with maximum brightness, if I decide to continue using the 420 I'll get a new main battery for it.

When I said the backup battery lasts about 1 second, thats for data retention only with the device off, the backup battery like in all other Windows CE devices cannot power the device (as in having the screen turn on). When the Jornada 420 was brand new in 1999 with a fully charged backup battery, the manual says it provides 1 minute of data retention so you only have 1 minute to change batteries (just like with Palm OS devices), and that's when it was new in '99.

I decided to try the Jornada 420 instead of my E-100 for to do lists (it's not a shopping list, I don't take it with me to the stores, I have my grocery list on my Windows Phone 7) and reminders for a while and will do frequent backups with the built in HP Backup program due to the bad backup battery. I synced all my data from the E-100 to the 420. The screen is only a bit smaller than the E-100's and I like that it can be turned on by touching the screen. It also has a more business feel to it than the E-100 that feels more like a gaming device.

One more thing, I thought the E-100 was thick, the Jornada 420 is even thicker!


Edited by aab 2014-09-01 10:37 PM
 Top of the page
Rich Hawley Page Icon Posted 2014-09-01 11:12 PM
#
Avatar image of Rich Hawley
Global Moderator
H/PC Guru

Posts:
7,188
Location:
USA
Status:
Wish I had a Win7 phone!
 Top of the page
Jump to forum:
Seconds to generate: 0.156 - Cached queries : 65 - Executed queries : 9