BenBret-1
I will definitely have to contend with cold temperatures in the coming weeks too.
In case there is something else to see like clouds
The most effective and attractive solution would certainly be to install a heating system.
Unfortunately, there is not much space inside the AM5.
The solution would be to replace the black cover with a 3D printed cover to create more space.
Then it’s possible to install a 12v control cabinet heater and at the same time a chinch connection. This can be controlled with a dew heater controller.
The heating elements I have looked at reach a surface temperature of 80 - 100 C.
So with my usual 25% on the controller I would have around 20 C heat output.
The same can of course also be done on the inside with 12v heater strips as Kevin just said.