Bob McGraw - K4TAX <RMcGraw@Blomand.net> wrote:
>A few weeks ago during a discussion of switching power supply and
>related noise, I made a comment that the charger for my laptop computer
>did cause noise.
>
>Subsequently I did find need to replace that charger with a new one.
>In comparing the two, one makes noise and one does not make noise. Now
>the interesting observations, both were made in China, both have the
>exact same rating, both have the exact same symbols for certification.
>
>However, what's observed different is this;
>(a) The one that does create noise has the following statement; "(1)
>This device may not cause harmful interference."
>
>(b) The one that does not create noise has the following statement;
>"(1) This device will not cause harmful interference."
>
>Now the way I interpret those two statements is statement (a) "may not"
>can be also presumed to mean that it may or may not cause harmful
>interference where as statement (b) is firm in that it uses the words
>"will not" is much more definitive and restrictive.
>
>Apparently there is something to the different "certifications" as
>earlier identified, and the results of same. In my case the one marked
>"WILL NOT" does not cause any RFI issues or noise issues with the HF
>reception.
>
>73
>Bob, K4TAX
>
>_______________________________________________
>TenTec mailing list
>TenTec@contesting.com
>http://lists.contesting.com/mailman/listinfo/tentec
That is an observation Bob and something I will have to look for on my power
supplies at home.
73-Eric
W9WLW
--
Sent from my Android device with K-9 Mail. Please excuse my brevity.
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
|