The Cyber-Spy.Com Usenet Archive Feeds Directly
From The Open And Publicly Available Newsgroup
This Group And Thousands Of Others Are Available
On Most IS NNTP News Servers On Port 119.
Cyber-Spy.Com Is NOT Responsible For Any Topic,
Opinions Or Content Posted To This Or Any Other
Newsgroup. This Web Archive Of The Newsgroup And
Posts Are For Informational Purposes Only.
From: firstname.lastname@example.org (leeppp)
Subject: Re: In search of special temperature sensitive Zener
Date: 12 Jan 2003 15:53:43 -0800
NNTP-Posting-Date: 12 Jan 2003 23:53:44 GMT
email@example.com (cornytheclown) wrote in message news:<firstname.lastname@example.org>...
> "Robert Sharpe" wrote in message news:...
> > Hi,
> > I am trying to replace a temperature sensor in an air conditioner unit (as
> > part of a custom installation) to decrease the minimum temperature that can
> > be set.
> > The existing information I have is :-
> > - The zener diode looks like a 1/8 w dark yellow axial with clear band in
> > middle.
> > - The operating voltage is about 3v.
> > - The voltage decreases at about 40mV/C
> > - Using a diode checker (with unit powered off) showed 0.6 v drop in one
> > direction only, high resistance is other direction.
> > I need to determine the type of diode and get a replacement that has
> > slightly lower nonimal voltage (about 2.8v at room temp) but with the same
> > temp coeff.
> > If anyone can help at all I would be very grateful.
> > I have tried :-
> > - searching Maplin
> > - searching RS-components and
> > - searching the web
> > with little luck (I can get plenty of 3v zeners but not with about the right
> > temperature coefficient).
> > Thanks in advance,
> > Rob
> where is this "zener" located, is it on a specific board or it the
> tmperature sensor for a digital thermostat ???
Make sure that it`s really a zener by testing it in a makeshift
circuit. you`ll see the zener "knee" (Simpson 260 needle just starts
to move upscale at knee.I then look at my DMM to keep the current at
safe levels)Zeners can get noisey and must be replaced if this
happens. I favor 1 watt replacement zeners and #LWAYS# test them b4
installation just to be sure as packaging is often mismarked as well
as circuit board silk screening. Nothing worse than a large
replacement cap due to improper board silk screening...tough on the
eyes and face when they go POW and crap flies every which way in shop.
The Boss Don like careless techz. There`s nothing like a 100mfd cap
going high order as power is applied. :D Lee 1/4W zenerreplacements
Go Back To The Cyber-Spy.Com
Usenet Web Archive Index Of
The sci.electronics.design Newsgroup