Great replies, thanks! I’ll look for an aviation device, it only makes sense that much testing and innovation is done in that area.

The second device sounds interesting also. The part I couldn’t understand was when they said that after it cut out when it reached 11.7 volts battery voltage immediately recovers. I hate to admit that some aspects of batteries are still a mystery to me. I gather that sometimes the inner chemistry will generate some electricity.

Another thing that concerned me is I think that on some cars 11.7 V is not enough to start it. The reviews are good, so perhaps these things are not the issue I think they might be.

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1986 300SDL, 362K
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