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It seems that there is a problem with the UO-14 power system - possibly a battery cell has a fault. This is causing the spacecraft to shut down during some eclipses. Since this is shutting down the whole spacecraft we can't implement an automatic routine to cycle the transmitter periodically to keep the transmitter on.

Currently we're running the downlink in telemetry mode to try and ascertain what's happening. We've also changed over to the secondary power system which is set up differently and will not shut down quite so easily - this may help but since we don't know the extent of the problem it's impossible to know at this stage.

We'll see how things go toward the end of the week and may switch back to FM repeater mode at that stage if things look OK. If the spacecraft continues to shut down, we may implement a system to switch the power back on automatically each time the spacecraft passes over Surrey.... Let's see how it goes...

UO-14 is getting on toward 14 years old and has completed something in the order of 74000 charge/discharge cycles of its nicad batteries - not bad really.... Lets hope it can manage a few more!

Chris G7UPN

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