1N4937 diode

[viliuks]

I wanted to ask if there are 1N4937 diode equivalents and where to find them (without buying them), I want to tear something apart and take the diode from there, because no electronic shops supply them without buying them in bulk and I only need 1 of them for a flyback driver

 

[djQUAN]

UF4007 (NOT 1N4007!) should work as a substitute.

 

[viliuks]

UF4007 (NOT 1N4007!) should work as a substitute.

I used 1n4007 and it worked, asked on other electronic forums plenty users told me it should work because it has somewhat same specifications etc. for my application

but here have a video of my thingy working

 

[Alien Laser]

Check out my project i made https://www.youtube.com/watch?v=sRHVvDHfO_0
op:

 

[djQUAN]

1N4937 is a fast recovery diode. UF4007 is the ultrafast version of the 1N4007 which is designed only for general purpose, mains frequency use.

If it works, then it must be luck. If the diode is only used for absorbing spikes then you could get away with it but for something that rectifies the output of a SMPS, I expect fireworks instantly.

 

[Cyparagon]

Why did you even ask for advice if you were just going to ignore it? 1n4007 is not going to work well at the 10s of KHz these things operate at. You will have significant reverse-recovery losses that will impede operation and greatly overheat the diode.

Replace it, or risk a fire.

 

[viliuks]

1N4937 is a fast recovery diode. UF4007 is the ultrafast version of the 1N4007 which is designed only for general purpose, mains frequency use.

If it works, then it must be luck. If the diode is only used for absorbing spikes then you could get away with it but for something that rectifies the output of a SMPS, I expect fireworks instantly.

Why did you even ask for advice if you were just going to ignore it? 1n4007 is not going to work well at the 10s of KHz these things operate at. You will have significant reverse-recovery losses that will impede operation and greatly overheat the diode.

Replace it, or risk a fire.

this was the chematic:
https://i.gyazo.com/07e67799ff907ce8cc2395b45185d938.png

I'm new to electronics to be honest, still don't really know the differences between diodes etc. and what it even does in the schematic, altough I know that the diode needs to be reversed. I could then replace it with the UF4007 that was suggested, if I could scavange it.

 

[Cyparagon]

I thought you were building a ZVS. This is even worse. The diode is for back-EMF protection for the BJT. It will not function well for this, either. So in addition to the diode potentially overheating, you may pop your transistor as well.

If you're new to electronics, that's all the more reason to TAKE the advice you asked for.

 

[viliuks]

I thought you were building a ZVS. This is even worse. The diode is for back-EMF protection for the BJT. It will not function well for this, either. So in addition to the diode potentially overheating, you may pop your transistor as well.

If you're new to electronics, that's all the more reason to TAKE the advice you asked for.

I'm aware of the transistor heating up, I'm not running it more than 30secs or so, I don't need it on for so long, it was an experimentation circuit, I actually ordered an already made ZVS driver which would be better