Zener Diode sorting question

[momo]

So I searched for zeners and read thishttp://www.diystompboxes.com/smfforum/index.php?topic=51330.msg387369#msg387369.
Am I supposed to go thru every diode I have, a bit like testing Ge's, until I find one that drops to 9.1v on a 15 v setup as in the link?

In other words, If a 1n4002 stays pretty much at same level as input voltage, I have to check them all because there might be a black sheep in there that would qualify?
Jeese, all I want is one darn 9.1v zener!

[R.G.]

Diodes are made for a specific purpose. Rectifier diodes are made to have at least X reverse voltage breakdown and Y current rating. They are tested to those limits so  you can be sure what you're getting. But rectifier diodes like the 1N4002 are tested to NOT break down with their specified max voltage.

Zener diodes are intended for breaking over at a specific voltage, and tested for breakover, where the rectifiers are not.

So if I'm baking up a batch of 1N4002s, I'll let them cool and test all of them for 100V reverse. I'll throw away any that do break over. Some of them may break over at 400V, but I won't care, they're good enough for labeling at 100V.

If I'm baking up 9.1V zeners with a 5% tolerance, I'll test them an and only sell as "9.1V zeners" the ones which break over between 8.649V and 9.559V. If I have some that are between 9.009V and 9.19V, I'll probably sell those as 9.1V 1% zeners.

If you have a batch of diodes, you don't simply go ferreting through them to try to find a 9.1V zener. Unless you once bought 9.1V zeners and just don't happen to know which ones they are, chances of finding one are very, very small. The chances of any diode marked 1N4002 breaking over at 9.1V are so small that I would not even try.

If you want a 9.1V zener, buy one.

NPN transistor bases are a special case. These tend to be made for about 5-7V breakover for modern transistors. But that's just an accident, it's not tested by the manufacturer and not guaranteed.

[momo]

Oh, OK, they do sell them!, I thought that a Zener was a result of an unwanted side effect and took advantage of that!...
So ill check Small Bear, ive checked my local Radio Shack, the guy looked at me like I was from another Galaxy!
Jeese, these people working there, they have no clue, just amazing!

Thanks again R.G(The Fantom!, always present, but invisible)!....just jokeing with you !

[markm]

So ill check Small Bear, ive checked my local Radio Shack, the guy looked at me like I was from another Galaxy!
Jeese, these people working there, they have no clue, just amazing!

......unless of course you want to purchase a Cell Phone. 

[momo]

Ah, so I reread your answer R.G...I alwayshave to reread your answers a couple times , you are like a bottomless well.....anyway so ,when you wrote:  'So if I'm baking up a batch of 1N4002s, I'll let them cool and test all of them for 100V reverse.', are you joking? or do you actually manufacture/build them?