Joe, I was on my 2nd winter activation on my local hill Sonnenberg, HB/LU-028, this Sunday, two days ago. It was a longer activation (80 minutes) with +/– favorable conditions: temperature around 4 °C, no snow, no wind, a table for my stuff nearby the hunters’ hut and a fence for my mast. So the equipment could acclimatize: the PA temperature of my KX2 showed around 11 °C.
I’d be unhappy, when I could not spot my SSB activation or not do the minimum number of QSOs for a proper activation. I experienced two things:
The iPhone shut down two times by itself and showed confusing percentages of battery charge afterwards. I had to keep it near the body for a minute or two to be able to turn it on again, although I had had it connected to a USB battery block feeding permanently. This could have been a problem for self-spotting, since this would affect sending SMS or using an app for spotting.
The output power of the KX2 went back from 10 watts to 5 watts in the last third of the activation time very often. Since I could not perceive any real technical reasons like antenna mismatch I suppose that the reason for this is the low temperature, too. Unfortunately, I did not observe the voltage in the display of the KX2. The vendor of my KX2 had informed my that they had never had problems with low temperatures on their own activations on higher mountains (rather the need of the operators for a cup of tea, hi).
No problems at all with the small tablet and VK port-a-log.
So my conclusion was: keep the batteries warm and the activation time short - by avoiding long stays outside at cold temperatures (incl. hiking time).
Can anybody from the readers contribute about their experience to keep the phone operating 100%? I cannot take it out and put it back into my clothes constantly, since I want to use it for SOTA watch, hi.
Has anyone experience with these small bags that are shaked initially and provide warmth for a certain period? Other/better ideas for longer activations? I think of keeping the KX2 battery in my clothes and connect it via cable to the power connector of the KX2.
It was an interesting testing afternoon for me on Sonnenberg to check out such details under harmless conditions.
Vy 73 de Markus, HB9DIZ