If you use this set up to power your radio, you will damage your batteries. A 5 amp draw from a radio is sufficient to ruin your batteries faster than you would think. The one battery where the 12 v draw is from will never fully recharge and the other one will eventually over charge. If you set it up this way already I would add a 5A capable battery equalizer to compensate for the unbalanced draw and you won't need to change anything.Scored a Pyle 720 off ebay for $20! So this weekend I am digging into the 24v to 12v step-down. I've been reading through a ton of threads on this, and most of them involve a 12v stereo. Since I don't need that, here is what I am thinking, basically following @mongoose2231 's diagram below.
24v off the high side battery and using the lighter into a relay so the step-down functions when the ignition is on. Running that to a 6-fuse Blue Sea fuse panel for a 12v cig lighter and ham radio. Thoughts? Should I ground the step-down separately or run it back to the battery?
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