Cheap op-amps from Aliexpress

[soggybag]

I ordered some op-amps from Aliexpress. Here's what I bought:

- TL022
- TL62
- TL072
- OP2134
- LM308
- LM386

The tl;dr is the chips were about $0.22 each and shipping took about 2 weeks. All of the chips seems to work fine, except the LM308 for some reason. I need to think of a way to look at these more closely.

Plugging the LM308 into a Rat clone produced no sound. So these seem to not work at first test. What would be a good way give these conclusive test?

http://www.super-freq.com/cheap-parts-from-aliexpress-com/

[Rob Strand]

Worth checking this out,

https://www.diystompboxes.com/smfforum/index.php?topic=128924.msg1243553

[antonis]

Plugging the LM308 into a Rat clone produced no sound. So these seem to not work at first test. What would be a good way give these conclusive test?

Any DC buffer configuration..
e.g. A DC power supply of any voltage between 5v and 35V, a mid-supply (or any other point between supply rails) voltage divider connected to non-inverting input, a short between inverting input and output and a measurement on output (or on inverting input)..

[Mark Hammer]

I ordered some CA3260 chips through them, to make some Mostortions, and only one of the 5 worked.  I thought the other 4 might be remarked single op-amps, but they didn't work in that configuration either.

[antonis]

A test board for "unknown" ICs should be an interesting tool..