On 9/8/04 5:42 PM, "Sathe Dilip" <[EMAIL PROTECTED]> wrote:
> It has basis in the days of vacuum tubes. It has to do with the > Tungsten filaments used in the CRT type monitors. Tungsten has a > positive temperature coefficient of resistance; the cold resistance > being about a third of that at the operating temperature. So when you > turn on a CRT from cold, three times the current flows through the > filament until it heats up. The theory is: Multiple turn-ons stress the > filament and it can fail earlier than when it is allowed to run hot (or > reasonably warm) when not in use. (You may have noticed how > incandescent lamps sometimes burn-out at the time they are switched on) > There are ways to limit the initial inrush current to avoid this kind of > damage. With proper attention to design, this should not be an issue > with modern CRT based equipment. Nor should it have anything to do with > the LCD type monitors. In the "old" days I used to arrange for the filaments of some of the vacuum tubes in my ham radio set to remain on even when the rest of the circuitry was turned off. This greatly prolonged the life of these tubes vs. turning them on and off a few times daily. Modern circuits are far less prone to this phenomenon, but transients still do occur to a degree when equipment is powered up. Well designed equipment is relatively immune to this phenomenon, but cheaper stuff still suffers a great deal. Anybody still using a 5 year old generic PC? This iMac is from 1999. -- Bruce ____________________________________________________ B R U C E K. klutch-at-erols.com -- The iMac List is sponsored by <http://lowendmac.com/> and... Small Dog Electronics http://www.smalldog.com | Refurbished Drives | - Epson Stylus Color 580 Printers - new at $69 | & CDRWs on Sale! | Support Low End Mac <http://lowendmac.com/lists/support.html> iMac List info: <http://lowendmac.com/imac/list.shtml> --> AOL users, remove "mailto:"; Send list messages to: <mailto:[EMAIL PROTECTED]> To unsubscribe, email: <mailto:[EMAIL PROTECTED]> For digest mode, email: <mailto:[EMAIL PROTECTED]> Subscription questions: <mailto:[EMAIL PROTECTED]> Archive: <http://www.mail-archive.com/imac-list%40mail.maclaunch.com/> --------------------------------------------------------------- >The Think Different Store http://www.ThinkDifferentStore.com ---------------------------------------------------------------
