-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 The Saturday 2006-09-09 at 10:24 +0200, Per Jessen wrote:
Basil Chupin wrote:
Ok, if you want me to call it a "speed controller" rather than a rheostat then to make you happy I'll call it a "speed controller" :-)
Personally, I'd prefer potentiometer. I had to go lookup what a "rheostat" is :-)
| From The Collaborative International Dictionary of English v.0.48 [gcide]: | | Rheostat \Rhe"o*stat\ (r[=e]"[-o]*st[a^]t), n. [Gr. "rei^n + | stato`s standing still.] (Elec.) | A contrivance for adjusting or regulating the strength of | electrical currents, operating usually by the intercalation | of resistance which can be varied at will. --Wheatstone. | --{Rhe`o*stat"ic}, a. | [1913 Webster] Here, in Spain, the word is old fashioned; by rheostat I understand a coiled wire device designed for power, ie, for directly controlling the current of a (relatively) high power device, as a motor or fan. A potentiometer is always very low power. Thinking about what Basil reported, the only explanation I can think of is that the computer was turning on and off the current fast on the fan circuit; being a coil, the rheostat can vibrate. That is, if his circuit is really a rheostat and not an active electronic circuit. I have found that effect when using a tyristor circuit (dimmer) to control an open air coiled wire stove: at some settings it vibrated, but softly. In fact, if you put a dimmer at middrange controlling a bulb, and poise a magnet to the bulb, you can see the filament oscillating wildly (and finally breaking). - -- Cheers, Carlos E. R. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2 (GNU/Linux) Comment: Made with pgp4pine 1.76 iD8DBQFFApqktTMYHG2NR9URAiCOAJ9K/ZW0o85KPDk/hTfn88mqfcoz8QCdE/gW dQfLEGRvqcSeFP2Gpx5P1S0= =Eptv -----END PGP SIGNATURE-----