Hey guys while troubleshooting a monitor yesterday I tried to test some mosfets and had some false results with my extech 330 multimeter. In diode mode it only puts out 1.5v while my junk drawer meter puts out ~2.5v. Am I doing something wrong or is my meter on the fritz?
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Hello experts,
Can anyone educate me on how to test MBR3045CT and SR3045LCT Schottky diodes? I'm totally a newbie in electronics, so forgive me if I have cheap tools. In my effort to repair a Gigabyte PSU, I stumbled upon the two diodes, which I suspect are leaky. I tested this with my two cheap multimeters and the newly bought LCR-T4 MC328, and I got confusing results. Below are my test results.
Aneng ST182 Meter.
Diode mode.
MBR3045CT:
Diode mode
Pin 2-1 - 0.150v
Pin 2-3 - 0.150v ... -
Unit came to me and customer said they spilled liquid on it. Opened unit and inspected board and saw no signs on liquid reaching the board. Plugged in amp meter and it pulled 20v and booted normally, i connected to internet and ran update on the OS. Came in the next day to test again to make sure unit was functional, now its stuck at 5v and 0 amps no power, no shorts found on so far.
Tested all CD3217 and RAA489900:
UF400
PP3v3_UPC0_LDO- 3.48v, .473 Diode
PP1v5_UPC0_LDO_CORE- 1.59v, .504 Diode
USBC0_CC1- 0v, .455 Diode
USBC0_CC2- 1.66v, .454 Diode... -
(I am self-taught in electronics over 20 years as a hobbyist, but I lack some of the fundamentals that folks who went to school for this would know... so please bear with me as I get deeper into this new hobby of retro computing...)
I'm familiar with diode mode in that it produces a small voltage between the leads and displays the the amount of voltage drop when the leads are connected... however....
Why do the board repair folks always put the positive lead to board ground and use the negative lead to probe the board itself? My intuition would be to put the negative... -
Hello, I am looking for help to replace a damaged diode. The tristar was replaced and a diode was damaged in the process. I have a picture of the diode but dont have an exact donor. I mostly have macbooks for donors and only a few ipad and iphone boards. Diode part number: DSF01S30SCAP
Im not sure where to find the ipad board number. Anybody have an idea where else this diode is used on other boards? Thanks.... -
Hello everyone, I'm repairing an LG TV backlight and I noticed some strange behavior when I touching the backlight strip with a missing Zener diode.
So I replaced the leds on the strips and they seemingly working fine, but soon as I touch the strip which has a missing Zener diode the whole backlight turns off for a few seconds and then turns back on.
Is this caused by the missing diode? If so what kind of zener diode should I use to replace it?.
The led strips has 9 6V leds.
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