On Mon, 9 Mar 2015 07:48:13 -0700 (PDT), John-Del
wrote:

On Sunday, March 8, 2015 at 8:39:44 PM UTC-4, Phil Allison wrote:

They were still to be seen in the dashboards of cars in the 1980s
and just termed regulators in the car repair manuals.

** Cars do not have electric heaters, but use hot water from the engine and a thermostatic valve plus fan to warm the interior.


.... Phil



It's true that cars did not use these devices as thermostats, but they did as mechanical voltage regulators, although it was much earlier than the 1980s. Here is a link to the instrument voltage regulator used in my 66 Mustang:

http://www.cal-mustang.com/INSTRUMEN...4762C1142.aspx

These open and close several times per second to provide an average of 5-6 volts to the gas, temperature and oil pressure gauges. The ammeter is of course self powered. A variation of these is used as a self resetting circuit breaker built into the headlight switch. Most people these days remove the guts from the IVR and replace it with a 7805 IC.

http://bob_skelly.home.comcast.net/~...tabilizer.html