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Ollie C

Very ill fat frog...

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Hey, at the school that I work at we have a Fat Frog that has for some time now been out of operation. Had a play around with it today and here's what it does, each time I plug it in a different set of LEDs illuminate (sometimes flicker). By angling the power lead and holding it like that I can get the LCD screens to illuminate but nothing appears on them. The floppy drive LED illuminates most times as well, whether there is a disc in or not. Connected to a monitor there is no output, the LEDs on the connected keyboard do flash as would be expected when the frog is plugged in though. I don't know how but today I managed to get it to reach the BIOS level, where it stopped at "Checking for upgrade disk" on the onboard LCD and external monitor. Some weirdness that I found with that was sometimes when I put the floppy in on that screen or turned it on with a floppy in (containing the upgrade files) it would restart a few times before getting stuck at the same screen.


I have cleaned out any dust from inside and checked the battery voltage and checked all connections internally... all seems fine.

Although this has been heavily used, it's been looked after and I can't think of many reasons for it breaking like this.

Any pointers or ideas are greatly appreciated.


Thanks, Ollie.


(Pictures attached of LEDs illuminated in the strange manor that they seem to like to at the moment.)



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My initial reaction to what you have described is that there may be a problem with the supply rails being too low so it is not powering up correctly.


There are a number of reasons for this.

Please could you e-mail me the desk serial number so we can date the hardware and firmware, then I may be able to help you track the problem.

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I know you checked the battery but based on that serial number the that age of desk the battery should be a rechargable one. What you need to do is check the battery voltage with out power this needs to be above 2.2v

With power it should be below 4.2v. If it is trying to draw too much current to charge this could be why the desk is not booting.

Also on that type of battery they can corrode in such away that they leak onto the PCB and cause damage to the tracks.


Did you manage to measure the supply rail into the desk from the PSU?


Again you may find it easier to e-mail me on the address below.

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Emailed you some time ago but have not yet received a reply. Only remembered now as the new technician was looking at it the other day.

And just incase the email didn't reach you..

I checked the battery with and without power, all fine. Checked the voltages coming from the power supply - they seemed fine.


We've recently acquired a Jester desk, is the power adapter for that the same as for the frog? If it is then I can try the frog with that adapter just to double check.

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