Badcaps.net Forum
Go Back   Badcaps Forums > Troubleshooting Hardware & Devices and Electronics Theory > General Electronics Technical Discussion
Register FAQ Calendar Search Today's Posts Mark Forums Read

 
Thread Tools Display Modes
Old 10-11-2018, 06:20 AM   #1
debugtimog
New Member
 
Join Date: Jul 2018
City & State: Kedah
My Country: Malaysia
I'm a: Knowledge Seeker
Posts: 10
Default please help to identify replacement diode

Hi All,
Please help me identify what is this unmarked crystal diode and how can I find its replacement partnumber.



Thank,
Attached Images
File Type: jpg diode.jpg (111.1 KB, 27 views)
debugtimog is offline   Reply With Quote
Old 10-11-2018, 08:58 AM   #2
stj
Great Sage 齊天大聖
 
stj's Avatar
 
Join Date: Dec 2009
City & State: Europe
My Country: some shithole run by Israeli agents
I'm a: Professional Tech
Posts: 19,499
Default Re: please help to identify replacement diode

only way to know is a schematic.
so what is the board from?
stj is offline   Reply With Quote
Old 10-11-2018, 10:29 AM   #3
budm
Badcaps Veteran
 
budm's Avatar
 
Join Date: Feb 2010
City & State: S.F. Bay area
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Knowledge Seeker
Posts: 34,260
Default Re: please help to identify replacement diode

Please provide the pictures of the whole board also.
__________________
Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956

Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999

Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl

Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/

TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809
budm is offline   Reply With Quote
Old 10-11-2018, 07:37 PM   #4
debugtimog
New Member
 
Join Date: Jul 2018
City & State: Kedah
My Country: Malaysia
I'm a: Knowledge Seeker
Posts: 10
Default Re: please help to identify replacement diode

Hi,
I have put an arrow to where the diode is, it is connected to the coil of the relay where i draw a box. At the bottom of the box is the normally open contact for the relay. The IC is lm393. This a power supply but i noticed when I plug in, the relay is not being powered on, thats why i am now focusing around this area.




Attached Images
File Type: jpg glass diode.jpg (192.4 KB, 53 views)
debugtimog is offline   Reply With Quote
Old 10-12-2018, 10:31 AM   #5
budm
Badcaps Veteran
 
budm's Avatar
 
Join Date: Feb 2010
City & State: S.F. Bay area
My Country: USA
Line Voltage: 120V 60Hz
I'm a: Knowledge Seeker
Posts: 34,260
Default Re: please help to identify replacement diode

1) The relay coil is driven by Q22 so is Q22 good and is it being driven to turn on to supply the current to the relay coil?
2) What Voltage testing have to done so far?
What Voltage do you have on each leg of the relay coil with ref to GND?
3) Where are the pictures of the whole top and bottom side of the board?
budm is offline   Reply With Quote
Old 10-14-2018, 07:20 PM   #6
debugtimog
New Member
 
Join Date: Jul 2018
City & State: Kedah
My Country: Malaysia
I'm a: Knowledge Seeker
Posts: 10
Default Re: please help to identify replacement diode

Thanks budm, I traced the voltage from q22 and it leads to a voltage regulator that is undervoltage, suppose to be 14vdc(relay coil voltage rating is 15v) and i measure 4volts.replaced the regulator and it did start up the power supply.

But I still dont know what/how to replace this diode. fortunately it wasnt defective and there was no need to replace it
debugtimog is offline   Reply With Quote
Old 10-14-2018, 09:35 PM   #7
R_J
Badcaps Veteran
 
Join Date: Jun 2012
City & State: ☻
My Country: Canada
I'm a: Professional Tech
Posts: 3,011
Default Re: please help to identify replacement diode

The diode is a minimelf diode SOD-80, The band color could identify the voltage/current etc.
Maybe a LL4150GS08

Last edited by R_J; 10-14-2018 at 09:49 PM..
R_J is offline   Reply With Quote
Old 10-29-2018, 10:38 PM   #8
csaba911
New Member
 
Join Date: Oct 2018
City & State: Edmonton
My Country: Canada
I'm a: Knowledge Seeker
Posts: 4
Default Re: please help to identify replacement diode

The designation is D10 is there any other diode have ZDxx? If yes than it’s probably just a generic 1N4148. De solder it and check with a multimeter diode test, if bad than try to install new 1N4148.
csaba911 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



Badcaps.net Technical Forums 2003 - 2018
Powered by vBulletin ®
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
All times are GMT -6. The time now is 04:57 AM.

Did you find this forum helpful?