Re: Cheap cables from China


 

I'm learning a lot about cables ;)

The cable jackets do say "RG-58/U" but, as mentioned, the offshore factory will print whatever you want. There have been documented cases where they lightly sand the top of whatever batch of IC's they have on hand (or even empty packages), and print the "correct" marking for the chips the customer ordered! They will go to the trouble of putting fake undersized die in TO-3 transistor cases, so they pass a superficial test but fail in use... Lots of stories here: https://hackaday.com/2018/01/15/is-that-part-a-counterfeit-here-are-a-few-pointers/
There used to be a great web page that had pictures of all the phony semiconductors but it seems to be offline.

Anyway. For comparing cables I would use the GR ones as my standard, thus compensating for any leakage from the transmitter and dummy load (unless, of course, said leakage swamps the hopefully small amounts from the cable under test). I also can generate about 20 watts at 148 MHz, which would be easier to detect than 30 MHz leakage...

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