Re: Beware Buck converters


Phil N6WKZ
 

Sverre,

I tested one of mine and found: 78 mv ripple at 68 KHZ. I guess that mine is a fake LM2596 too. Probably most of those $1.00 Buck converters are fake.

Thanks for the link! I used the same setup as in the link.

73

Phil N6WKZ

On 12/9/2019 12:04 AM, Sverre Holm wrote:

I use the cheap 2596 converters for my U3S also and the work well.

But there is something suspect about them. Mine have switching frequencies around 50 kHz, but an LM2596 is supposed to switch at 150 kHz. See https://k6jca.blogspot.com/2018/02/counterfeit-lm2596-regulator-boards.html

Whether this matters or not, I don’t know, but I think there is reason for suspicion when there is such a large discrepancy.

73, 
Sverre, LA3ZA

http://la3za.blogspot.com

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