Date: 8 Dec 1998 15:55:13 GMT From: FEDavisnopsamdnet.att.net (Fred E. Davis) Subject: Re: Average speed
On Tue, 08 Dec 1998 06:10:27 -0800, Justin VanAbrahams <jvanabranopsamnet> wrote: >At any rate, the SID and the speedo get their information >from EXACTLY the same place... Well, yes and no; the speedometer receives an AC signal from a sensor in the gearbox whose frequency varies with speed (9.382 Hz/km). The speedometer shapes and divides this signal by four, and feeds the EDU, speed control, etc (2.458 pulses/km). >... and display it in exactly the same way. Not exactly, since the EDU uses a digital display, while the speedometer depends upon a mechanical indicator and its associated errors (such as friction, parallax, manufacturing variations, etc). >Pick up a wiring diagram for the cars if you do not believe me. For anyone with electronic skills, you should have the manual anyway; it makes a very interesting read. It does not, however, tell the whole story for every question.