[TechAssist] Re: Zener diode test
- From: Paul <dntwntv@xxxxxxxxxxxxx>
- To: techassist@xxxxxxxxxxxxx
- Date: Thu, 9 Jun 2005 14:12:33 -0700 (PDT)
I don't think they are causing problems either after checking for go or no go.
The meters both have relativly new batteries so would be surprised if that were
the cause, but it might be worth a try anyway. This whole thing came about
because this board is NLA per Andrews, where I buy most of my parts. Another
surprise for a 2 year old 32"Sony. However the unhappy customer called Sony
and they told the customer that is was available under a new number,and further
that if they had called an asc he would have known that. Not sure how the asc
would have information that the parts house dosen't? So I decided I would
repair the board and that is where this all started. Going through the board
ran across these odd diodes. The tact switches on this board cost more than the
whole board ready to go.
Paul
Jim Myers <jr.myers@xxxxxxxxxxx> wrote:
Look up MTZJ-T-77- in NTE and you'll find a fair selection of various
zeners, the first few on the list, up to 10 volts require a test current
of 20ma and the rest require only 9.5ma or less. Maybe a new battery in
your meter WOULD make a difference. In any case if they are used as a
protection device on the A/V inputs and are not shorted they are
probably not causing any problems.
********************************
Since 1972 *
Jim Myers *
Telrad Electronics *
Fort Wayne Indiana *
********************************
Paul wrote:
> Yes, I agree. They appear to be just 1/2w Zeners, although very small glass
> cases. I measured a 9.1v, 1w that I had in stock and it measured fine on both
> meters. Interesting though, I checked to see if they would zener and they do
> 9.4v. They still don't front to back. How do you figure that? These are in a
> 2 year old set and are used in the A/V input circuit apparently as protect.
> Paul
>
> Jerome Silverman wrote:
> Sounds like plain vanilla 9.1 volt zeners. But to answer your question, some
> "zeners" are actually ICs and some have one or more forward biased diodes in
> series with the zener element and some may consist of two or more zener
> elements in series.
> Jerry Silverman
> Greentron Inc
> 4 Newland Ave Greenville SC 29609
> Fax/Phone 864 232 3889
> greentron@xxxxxxx
>
> ----- Original Message -----
> From: "Paul"
> To:
> Sent: Wednesday, June 08, 2005 9:44 PM
> Subject: [TechAssist] Zener diode test
>
>
>
>>Are there zener diodes that cannot be measured? I have 4 Sony zeners P/N
>
> MTZJ-T-77-9.1B on a board. They do not cross and I am guessing they are 9.1v
> zeners. They all are either open or they do not measure. Have lifted one end
> and measured with two different meters,Beckman and a Fluke still no reading.
> Can't believe all 4 are open.
>
>>Paul
>>
>>Paul ,B
>>Central TV&Video
>>911W Grand Ave
>>Grover Beach Ca.
>>(805)481-8084
>>
>>--------------------------------------------------------------------------
>
> ---
>
>>This Email List is Public. Remove: http://www.tech-assist.org/remove.htm
>>Lost Password: http://www.tech-assist.org and select "Login Problems?".
>>Appliance Repair List:
>
> http://www.tech-assist.org/secure/tip/chatjoin.htm#app
>
>>Email Archives: //www.freelists.org/archives/techassist/
>
>
> -----------------------------------------------------------------------------
> This Email List is Public. Remove: http://www.tech-assist.org/remove.htm
> Lost Password: http://www.tech-assist.org and select "Login Problems?".
> Appliance Repair List: http://www.tech-assist.org/secure/tip/chatjoin.htm#app
> Email Archives: //www.freelists.org/archives/techassist/
>
>
>
>
>
> Paul ,B
> Central TV&Video
> 911W Grand Ave
> Grover Beach Ca.
> (805)481-8084
>
> -----------------------------------------------------------------------------
> This Email List is Public. Remove: http://www.tech-assist.org/remove.htm
> Lost Password: http://www.tech-assist.org and select "Login Problems?".
> Appliance Repair List: http://www.tech-assist.org/secure/tip/chatjoin.htm#app
> Email Archives: //www.freelists.org/archives/techassist/
>
-----------------------------------------------------------------------------
This Email List is Public. Remove: http://www.tech-assist.org/remove.htm
Lost Password: http://www.tech-assist.org and select "Login Problems?".
Appliance Repair List: http://www.tech-assist.org/secure/tip/chatjoin.htm#app
Email Archives: //www.freelists.org/archives/techassist/
Paul ,B
Central TV&Video
911W Grand Ave
Grover Beach Ca.
(805)481-8084
-----------------------------------------------------------------------------
This Email List is Public. Remove: http://www.tech-assist.org/remove.htm
Lost Password: http://www.tech-assist.org and select "Login Problems?".
Appliance Repair List: http://www.tech-assist.org/secure/tip/chatjoin.htm#app
Email Archives: //www.freelists.org/archives/techassist/
Other related posts:
