On 2017-07-12 11:51 AM, Mark Phillips wrote:
This thread has been useful for some other projects I have going at the moment. I think the "proper" way to do this is to power the Pi from a 12V source and a buck converter. There are any number of 12V pwrgate doo-dads that you could make to handle the UPS side. I found this on Thingiverse that is not only a Pi case but also has a buck convertor too .... https://www.thingiverse.com/thing:2286741
<-- Hi Mark: Yeh using a battery and a 'buck converter' is definitely an option. As I mentioned to Carl the 'CPT' branded converters that I have, are "noisy" they inject audio back into the audio path of the fob, so the audio into the network as well as audio out on your transmitter has an annoying high pitch whine. In my case, since I intend to install this stuff thousands of miles away, I don't want a battery down there, left unattended. A quick search on Amazon, revealed one of these: https://www.amazon.com/Kaito-KA-723-Portable-Pass-Through-Compatible/dp/B071... It supports 'pass through charging' - but does not mention anything about seamless switch-over from AC power to battery power. Of course, some surgery and an electrolytic cap across the output may help during short 'brown-outs' Good to hear from you... catch me on 27919 sometime! Cheers, Ramesh.