Eh. Not the best idea. In a pinch, yes. But despite the thousands of nearby batteries, in a true emergency, no one is letting you use their car battery. The only car battery you can count on to use is yours. So you connect it up, start to use it (remember, these are not deep cycle batteries, so you really can't use it for long), and you don't want to waste gasoline to charge it (since you may have to evacuate at some point and you want all the fuel you can muster). After awhile, it isn't starting your car. Now you have to evacuate and there you are with a dead battery and a car that won't start. Now is the time to research and build yourself a dedicated backup power system to run your radios based on your needs, budget, and proper design. But I agree, in a pinch, you should be able to connect to your car's electrical system. But I would use that as a system of last resort. Also, you often can't get the car close enough to where you are operating, so now you're dealing with long cables and voltage drop, etc., or pulling the battery to move it - which is a problem that you don't want to have to deal with while you're trying to get radios up and running.
I have a LiFePO4 RV 200 AH battery and two 100W solar panels. I also use a failsafe charger that keeps the batteries above low voltage dropout in cloudy conditions. There's a boost charger to bring the batteries up when anticipating a storm (or a contest!) My portable battery is a 25 Ah parallel/series lithium stack of analyzer matched cellphone batteries.
Thank you.....The best one source dissertation on this subject I have seen. My own station is runs off a Grp 29 truck battery for an IC 7300, Hercules II amp to a OCF dipole. Charged from the grid with a 10A Xantrex Charger, with my limited operating time, of an hour per day, I don't charge very often.
Well done Julian; one of the best and well organized video productions I've watched addressing the most important topic for Radio Amateurs'! Hopefully we will see a quality video from some of the commenters covering their ideas of same very soon, ; )
Great video! Best point: Get off grid now! My station is off grid. Please call me if grid goes down, I may miss it!
I am new to battery backup power, portability, and the why and wherefore of establishing a backup power source for my radio gear. I found your presentation full of information that I should want to become more familiar with. I'm not a rocket scientist, so I hope future presentations on the subject will be addressed on a level that will educate and not leave me in the dust. Anyway, I appreciate the content and thoughtfulness of your videos.
