开云体育

Single Messages Topics Expanded Polls

Re: How to find this signal with all its harmonics

W0LEV All Messages By This Member #19334 Ericd, you are one of the few these days!!? THANK YOU!!! My experience over the past decade (retired) and the last three decades (working the previous 2 to retirement, I have had many.....many instances of China just printing labels.? The last 4.5 + decades, I worked as an EMC/RFI engineer for a number of companies including HP and finally StorageTek (the last one I was actually requested to cheat - which I refused and led to firing).? Not on my watch but at HP, our scanners in Germany big-time failed due to "overlooking" and completely creaming reception of TV channels 2 through 6, including commercial FM due to radiated emissions.? Of course, that put us under the microscope and forbid HP from selling scanners in the whole EU for a year.? Another instance:? We upgraded our test computers to test our storage libraries at StorageTek (we had a good OATS).? They came with no regulatory stickers from SuperMicro.? We contacted their West Coast storefront about the issue.? They immediately ask, "How many do you need?"? A week later we received a business envelope full of "just printed" regulatory stickers. And another:? Requesting reports of products which failed formal testing.? Of all my requests, I received usually around 30% of those requested.? What's even more disgusting, none of the reports applied to the product I had requested.? All.....ALL.....of them were just compilations of pages from other unrelated regulatory reports with appropriate title pages.?? More yet:? I have tested, both officially and pre-compliance, many Chinese produces which miserably failed both radiated and conducted emissions per FCC and/or the EU regulations. ? Appliances:? The ultimate responsible party is the integrator of "components" (SMPS) which sail through customs as components.? Except for the German products we have in our 10-year old kitchen,? everyone fails both conducted and radiated emissions.? I had to install an extremely robust common mode choke on our second frig/freezer, a Kitchen Aid, to reduce both radiated and conducted emissions.? They go together as once the conducted emissions are violated, the whole house wiring lights up.? No surprise..... To make things worse, I'm an amateur radio operator and pursue radio astronomy as yet another hobby.? Get the point???!!! In my experience over the decades, China has taught even some of the good and upstanding companies the risk of cheating isn't that great with an FCC that no longer cares about enforcement.? Have a read of my QRZ page for a bit more.? I could fill anyone's email inbox with stories addressing China and the regulatory world.? And let's not mention S. Korea that uses the regulatory world as a trade barrier. Dave - W?LEV? ? toggle quoted message Show quoted text On Sun, Feb 2, 2025 at 7:24?PM Erik Kaashoek via <erik=[email protected]> wrote: On Sun, Feb 2, 2025 at 10:38 AM, W0LEV wrote: China just prints labels and applies them appropriately with absolutely no attention or testing to international RFI/EMC regulatory laws.? Dave, This may be a bit too general. Much of the modern electronic equipment is manufactured in China, including from very well respected brands. It may be better to state that very cheap stuf you can buy on Aliexpress and similar webshops may lack attention to international RFI/EMC. But even that is not always true. An example is the tinySA. It is cheap and available on Aliexpress and we took great care it is adhering the international RFI/EMC regulatory laws. So, as a kind request, please do not generalize too much as it does not help uncertain buyers. -- Designer of the tinySA For more info go to -- Dave - W?LEV

View All 11 Messages

#19334

Join [email protected] to automatically receive all group messages.