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.
NNTP-Posting-Date: Sun, 12 Jan 2003 18:44:15 -0600
From: firstname.lastname@example.org (John Fields)
Subject: Re: In search of special temperature sensitive Zener
Date: Mon, 13 Jan 2003 00:27:14 GMT
Organization: Austin Instruments, Inc.
X-Newsreader: Forte Agent 1.5/32.451
X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers
X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly
On 12 Jan 2003 15:53:43 -0800, email@example.com (leeppp) wrote:
>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
That's not the proper way to test a Zener. What you should do is
force the specified test current through it and then measure the
voltage drop across it to determine whether it's in spec. If it
won't break down then it's either not a Zener or it's open.
>Zeners can get noisey and must be replaced if this
How do you measure that, and what is your noise criterion for
>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.
If you replace a smaller Zener with a 1W unit the test current
required to push its voltage over the knee will be higher than that
required for the smaller Zener, so there is no guarantee that the 1W
Zener's voltage will be the same _regulated_ voltage the smaller
Zener supplied. In general it's not a good idea to be making
"upgrades" unless you know what you're doing...
Professional circuit designer
Go Back To The Cyber-Spy.Com
Usenet Web Archive Index Of
The sci.electronics.design Newsgroup