Megasat no signal

I have a megasat I’ve updated the software & im still not getting a signal the standby is flashing red all the time and the dome is buzzing I’ve also tried pressing the 2 arrows to reset but still the flashing red light ? I have had a second battery fitted recently (not 24v) and a solar panel?

When you say you have had a second battery fitted, is this joined to an older battery

That may be your problem

That is a big no no.
Both batteries in a pair should be the same make, size and age. Batteries of different age and/or size and/or design internally will have different internal resistance. The one with the lesser internal resistance will take most of the charge and do most the work. The idle one will die prematurely from lack of charging followed by the other one from being overworked.
That's the layman's version, THIS is the techie version
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