SMA & RF Connectors: China Sourcing Reference
1 resources tagged with "Sma"
SMA, RP-SMA, MMCX, and U.FL/IPEX are the RF connectors that show up on nearly every wireless module from China, and small spec details break links. SMA is rated to about 18 GHz with the right grade, but VSWR and gold-plating thickness on the center pin separate a usable part from one that radiates loss; the most common field mistake is confusing SMA with RP-SMA, which have reversed center contacts and won't mate correctly with the antenna. For Wi-Fi, LoRa, and GPS products, a cheap U.FL connector with a poorly crimped coax is a frequent cause of weak range that gets blamed on the radio.
When sourcing RF connectors, you're matching connector type, polarity, frequency range, and VSWR to your antenna and radio. We verify SMA vs RP-SMA polarity, gold-plating quality on the pin, and frequency rating, since a mismatched polarity or lossy connector quietly kills RF performance.
Wiki (1)
FAQ
What's the difference between SMA and RP-SMA?
RP-SMA (reverse polarity) swaps the center pin and socket compared to standard SMA, so the two won't mate correctly. Wi-Fi gear often uses RP-SMA. Ordering the wrong polarity is the single most common RF connector mistake.
What VSWR and frequency should an SMA connector support?
A good SMA part is usable to roughly 18 GHz with low VSWR; for 2.4/5 GHz Wi-Fi or sub-GHz LoRa you have plenty of margin. Watch gold-plating thickness and center-pin quality — that's where cheap parts add loss.
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