Hi, First time poster here though I've been following the EEVblog's YT channel.
I am a fledgling electronics hobbyist.
I'm attempting to fix a TV power board which had no standby power and noticed that I was getting 0 v on the 12 V rail that went to the digital board. (I also checked that there was around 2V AC.. so I'm hoping it didn't blow the digital board..)
Here's what I did.
1) I opened up the back of the LED tv and the first thing that I noticed was bad was a ceramic capacitor. I replaced that.
2) The STBY5v still wasn't available, I went checked the power board and noticed the bridge rectifier was also busted. Replaced that as well.
3) But still no STBY5v.
I went online and downloaded the schematics for the power board and poked around with my multimeter.
I came across a weirdness that lead me to believe that two diodes were busted/shorted. I tested the two diodes in circuit using diode mode. One orientation gave OL. The other orientation gave me a beep. Weird. So I took out the two diodes from the circuit and tested them out. Same results.
Unfortunately, I couldn't identify the SMD diodes. I've searched online and haven't quite come up with what it is. I've used the schematic's info and it just points back to the schematic. I've looked at [1] and am unsure if I'm looking at it correctly. I have a bunch of SMD components that I 'think' are diodes at home that I salvaged from other items. I'd like to replace these busted diodes but unfortunately, the diodes I have I haven't fully identified yet; but at least some of them have some sort of identification.
Here are the diodes in circuit.
Here's the schematic part.
Given all that, can someone point out how I can easily identify these diodes? The closest info page was [1]; but looking at the schematic, they are normal diodes (with the normal diode schematic symbol) and not schottky or zener diodes but it says in [1], the B list contains mostly zener and schottky diode info. So I'm guessing I'm looking at this wrong.
Any help appreciated and thanks!
ed