| ANTIQUE-RADIO-LAB Antique Radio Forum for Collectors antique-radio-lab.forumotion.com |
Posting Questions, Please supply ALL the details you have.
In order for Us to answer if We can!: You will need to provide Details,
such as 1-Brand Name of the Radio 2-chassis number 3-Model number 4-symptoms.5 Photo's
|
| | Zener diodes | |
| | Author | Message |
---|
Cliff Jones Site Administrator
Join date : 2010-11-22
| Subject: Re: Zener diodes May 6th 2014, 3:10 pm | |
| Also you can stack 2 (two) 4.1v zeners to get 8.2 volts ( if my college lab work was worth it ) _________________ I'm a Science Thinker, Radio Tinkerer, and all around good guy. Just ask Me!
|
| | | FrankB Moderator
Join date : 2010-11-22
| Subject: Re: Zener diodes March 10th 2014, 5:51 pm | |
| NTE5122A 8.2v 5w
This will work for you. |
| | | Guest Guest
| Subject: Re: Zener diodes January 3rd 2014, 2:58 pm | |
| Double checked; still no 8.2 v./2 w. Zener diodes. I now believe that no such animal exists and that the original project calling for this nonentity was made up. |
| | | Guest Guest
| Subject: Re: Zener diodes November 5th 2013, 1:26 pm | |
| Still don't see the 8.2 v./2 w. Zener diodes I was looking for in above post in Digikey's site, so will no longer look there. |
| | | FrankB Moderator
Join date : 2010-11-22
| Subject: Re: Zener diodes March 17th 2013, 10:21 pm | |
| On the unmarked diodes you have to sort of guess.
A good ohmmeter can tell you if its silicon or germanium.
If you think its a zener you can use the following procedure to check its break down voltage rating. (I have posted this before on several forums.)
Use an eye type capacitor bridge with VARIABLE output testing voltage.
Hook the suspected Zener across the 2 test terminals with correct polarity, of courrse; and put the tester on a test position for looking at the breakdown voltage of a capacitor.
Hook a voltmeter meter across the 2 test terminals.
Crank up the test voltage and see when the voltage fails to go farther up on the meter; i.e. If the meter indicates 150V and you have the test voltage cranked up to 250, the diode is a 150V Zener.
There is a built in current limiting resistor in the old eye tube testers, and the diode wont be harmed IF its really a Zener.
If its not, well, I have never tried the test with a normal diode.
Now most of the old eye type testers go to 600V, so it IS possible to have a zener with a breakdown voltage in excess of the 600V. A very rare, but possible circumstance.
I have used this method for years with 100% success so far.
This test is fantastic for the "shock pack" type assortments of unmarked and mis- marked zener diodes as well as those salvaged from TV's and such. You can also easily tell if the zener is leaky too. |
| | | Guest Guest
| Subject: Re: Zener diodes March 17th 2013, 6:54 pm | |
| I have lots of NOS diodes etc. From the 60's on I guess. How do you ID these small glass ones? |
| | | FrankB Moderator
Join date : 2010-11-22
| Subject: Re: Zener diodes March 9th 2013, 6:24 pm | |
| Should be available from NTE. |
| | | Guest Guest
| Subject: Re: Zener diodes November 28th 2012, 2:08 pm | |
| I bookmarked the Digikey page and will watch it for restock info. |
| | | Cliff Jones Site Administrator
Join date : 2010-11-22
| Subject: Re: Zener diodes November 28th 2012, 7:55 am | |
| They are out there but finding 2 watt is a bit harder. I'll look some more,found one! dang not in stock!
Click here for Digikey _________________ I'm a Science Thinker, Radio Tinkerer, and all around good guy. Just ask Me!
|
| | | Guest Guest
| Subject: Zener diodes November 28th 2012, 6:00 am | |
| A project I'm interested in calls for 8.2 v./2 w. Zener diodes. Two questions: (1) Does such a rated Zener diode exist? (2) If so, who sells it? I can't find this rating at any of the usual parts sources. |
| | | Sponsored content
| Subject: Re: Zener diodes | |
| |
| | | | Zener diodes | |
|
Similar topics | |
|
| Permissions in this forum: | You cannot reply to topics in this forum
| |
| |
| |
|