Trying not to panic.....yet. My 620LX will not start

ah, i see, and the 620lx has such a system where the battery will absorb everything?

i can tell you the 720 doesn't.

All batteries will absorb up to a limit. You'd need a hefty current overload to bypass it, something to make it go bang I would imagine. I don't think that you can easily conclusively prove that the 720 device died of an AC spike.

i can as unit was taken apart, the cause of its death has been identified (yeah power surge).

btw when it happened, the j720 was sitting happily on AC, turned off, battery was already fully charged... then suddenly the charge LED went off... and the owner couldn't turn on the 720 any more...

nothing was hurt except some stuff on the motherboard, but all other parts work fine according to our tests... poor thing, now i can't even use it to charge my batteries in it (charging circuitry is dead).

ok back to topic...

Well, I am an electronic engineer by degree, so I have had a lot of practice navigating around circuitry . I have tried the RFI trick and a wideband radio receiver which I have here at home, but that has proved to be anything from fruitless to inconclusive.

I removed the RAM/ROM module and reseated it and the unit still will not fire up.

I think we have covered just about all the reasonable options. Pity though, it took a while to get an IrDA and the network card so I could finally synchronise it, load it with software and give it ethernet/internet connection. I was really enjoying the ease of its use. Have been feeling a bit lost without it these last few days



Well the charge light on the unit was green when it failed, which indicates that the battery pack was fully charged at the time. Even still it should be really unlucky for a spike to cause the unit to fail even with a full battery, but in theory I guess I cannot rule that out. I am still at a bit of a loss though. If I had dropped the unit onto the floor or was treating it roughly or spilled water onto it etc which caused failure I could understand. But it failed just as I was sitting on my couch just casually surfing, and it had been treated relatively delicately up until then so a voltage spike isn't entirely out of the question because I have no other reasonable theory. Doesn't make it any easier though. I miss my little machine

Looking at trying to get another one now....

well, if it was FULLY charged it is not normal you got 6.9 volts for the battery!! probably we got the cause of the death...

one of the reasons why i never leave my stuff on AC after they have been fully charged .....

luckily 620lx's are cheap on ebay
or maybe upgrade to a newer hpc? a jornada?

but it still surely isn't easy, you saw my phenom ultra (10 volts vs 9 volts) thread... it is surely cheap, and even if rare i managed to win another, and i'm still so sorry for this one

Well maybe I failed to mention that this is what I measured the battery voltage to be after a long time left out of the unit. Maybe about 24 hours, while I was trying to hard reset it. It's possible the cells don't hold charge as well as they used to, but all rechargables degrade over time. This is a very common problem. We all wouldn't be very happy owners of HPCs if everytime the battery pack started to degrade over time, it helped blow up the unit

But on closer examination of the pack, the label writes that it is part number F1250-80001, which I lokked it up and is the correct battery pack for the 620LX and 660LX units. It also writes that its rating is 7.2V / 1.35Ah. So 6.9V doesn't seem altogether unreasonable if it has been left isolated for 24 hours after charging?

I have been looking at Jornada. However my finances right now are limited. We had family friends and their kids from interstate spend a week with us just now and we were spending money wholesale. I cannot justify spending money on a Jornada for the next little while as much as I would love to get one! . Unless it was a really good deal.

Edited by Britty 2006-03-25 9:03 PM

i believe it is absolutely unreasonable for it to be 6.9 volts after 1 day of non usage. 7.2V is just the nominal voltage, but normally it gives significantly more than 7.2. when it reaches 7.2 during discharging it is already quite low, and 6.9V is very low. then it discharges much faster regardign the voltage (think seconds or minutes here!) and at 6.0 it totally cuts off supplying power to the unit. (it has two cells, each is 3.0V then, and if you discharge them below 3.0 each, that can cause damage to the battery.) oh and li-ions have a low self discharge so if it gets from 8.2-8.4 to 6.9 within 24 hrs... oops then. so, this is as far as i know.

btw, what would be a good deal for a jornada? 680 or 720?

Actually I'm not sure . I looked pretty quickly at some prices for a 620LX and they are going for about $60AUD (about 25GBP or $45USD), plus added cost to ship etc from GB. I could more likely afford this in the shorter term than say a Jornada 720. They seem to private sale on local ebay here for about $250 - 300 AUD (100-120GBP, $180-220USD). This is what is average I guess. A good deal to me would have to considerably less than this. Not because I don't think they are worth it, but mainly because I cannot justify the expense at this point in time.

Edited by Britty 2006-03-25 9:41 PM

well, i'm sure later you can justify it...

i couldn't myself either, so i waited until a 175$ jornada 720 surfaced - this was years ago... then i shelled out the money for it, for a spare battery and for two bluetooth cards out of three that i won on ebay before finally one of them arrived... by the time i got wifi i started to feel i'd spent too much money on this thing. then a j728 surfaced locally... i couldn't resist it. it was hard to justify, very hard. i wanted to sell the j720 but in the end i never got around to that... i still have it (yes you all on hpcfactor predicted this a year ago and i wouldn't believe you!!)
a few months later... found a *very* cheap MP900 and then i couldn't stop.

be careful you'll have the same fate sooner or later!

I know what you mean. I have the bug. I know I cannot justify buying a 720 right now, but I need a HPC! The price of another 620 is within reason. So I think I will chase one up and this will keep me pacified until that good 720 deal comes along.

Am I a bad person for thinking I wish friends didn't come to stay so I could afford a 720?

Edited by Britty 2006-03-25 10:02 PM

nah you're not a bad person...

good plan though.. hope you can get them soon!

I'm sad that it has turned out this way. But at least I already have the power pack/IrDA and ethernet card already here ready to go the instant I get a replacement

I'll have to find the time to refurbish the battery pack though. That should be fun, I like to tinker.

Thanks everyone for all your suggestions. I would have liked it to all have been a more positive result, but that's life sometimes.

I will still haunt the forums while I get up and running again sometime in future.

Nope, I'd be handing them a bed and breakfast bill prepared on my 720

I Suffered the same panic now, I tried to turn on my MP 770 and appear nothing in screen, but when I connected into AC Power it turned on... The only problem was the PCMCIA Card that stay alive HPC, and drained my batteries...