For many years, the big manufacturers of mobile two-way radios (like Motorola and RCA) employed the most basic of components to 'protect' their early transistorized products from damaging 'load dumps' and the inductive kicks seen during engine cranking - using basic LC low pass filters comprised of a modestly-sized iron-core choke in series with 12 V Batt to a capacitor 'shunted' to ground. This is usually the 'first line of defense' in such a radio. Such filters were also employed to remove alternator 'whine' (this was years before any sort of integrated IC regulators were available, let alone today's low drop-out designs) and solid state devices were still expensive (for any application - including audio). I've successfully used simple RC filters when the current drawn was low enough. Failure to use *anything* has resulted in my losing 'chips' as hardy as the venerable LM555 ... Jim ----- Original Message ----- From: "Benjamin Bromilow" To: Sent: Thursday, January 10, 2002 6:26 PM Subject: Re: [EE]: Car power supply challenges > From: "Byron A Jeff" > > > That's a seperate issue that has been addressed in many > forums. A > combination of a fuse, MOV/TVS, and a > > shunt regulator can handle the spike issues. > > Excuse me for asking but what is/are MOV/TVS?? > I'm working on an automotive project and I've just begin to think about > voltage spikes!! > > Ben > -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body