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EI SUPER CLOCK battery
- Thread starter FLTENG
- Start date
I just went through this with the EI ASC-5A - basically a Super Clock (even shares some manuals), but with added altitude alert function. Would not keep time when there was no ship's power. Supposed to have internal battery.
So, I opened it up. Battery? What battery? Double check manual, yes supposed to keep time without any keep alive power. Gotta be a battery here... I see a Dallas Semiconductor RTC module (real time clock). Recognized that name from decades ago.... Battery has to be near it. Dang. At last a light goes on, you don't suppose...
Yes the lithium battery is built into the RTC module and then potted in epoxy.
And the RTC module is obsolete. So if you find one the internal battery will be dead from running the clock for many years.
On some PC forums, people fixing old IBM PS2 computers have taken to dremeling into the module.... different part number so I wouldn't count on the desired spot to be identical.
Bottom line... unless you can find a drop in replacement for the DS1603 ... or dissect one... you are pretty much out of luck.
Also looks like not much fun to swap the module as you can't get to the solder pads without splitting the boards.
Perhaps... with some surgery --- you could run an additional wire for keep-alive power directly to the DS1603 clock. https://www.analog.com/media/en/technical-documentation/data-sheets/ds1603.pdf 5 volts at 1 mA (worst case). An external lithium 18650 cell would be plenty.
The clock module is the black box under the bottom board. You can see how the pins for it are inaccessible without separating those two boards.
So, I opened it up. Battery? What battery? Double check manual, yes supposed to keep time without any keep alive power. Gotta be a battery here... I see a Dallas Semiconductor RTC module (real time clock). Recognized that name from decades ago.... Battery has to be near it. Dang. At last a light goes on, you don't suppose...
Yes the lithium battery is built into the RTC module and then potted in epoxy.
And the RTC module is obsolete. So if you find one the internal battery will be dead from running the clock for many years.
On some PC forums, people fixing old IBM PS2 computers have taken to dremeling into the module.... different part number so I wouldn't count on the desired spot to be identical.
Bottom line... unless you can find a drop in replacement for the DS1603 ... or dissect one... you are pretty much out of luck.
Also looks like not much fun to swap the module as you can't get to the solder pads without splitting the boards.
Perhaps... with some surgery --- you could run an additional wire for keep-alive power directly to the DS1603 clock. https://www.analog.com/media/en/technical-documentation/data-sheets/ds1603.pdf 5 volts at 1 mA (worst case). An external lithium 18650 cell would be plenty.
The clock module is the black box under the bottom board. You can see how the pins for it are inaccessible without separating those two boards.
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