"A",
"B",
"C",
"D",
"E",
"F",
"G",
"H",
"I",
"J",
"K",
"L",
"M",
"N",
"O",
"P",
"Q",
"R",
"S",
"T",
"U",
"V",
"W",
"X",
"Y",
"Z"

SMA Connectors
SMA: The 'Sub-Miniature A' connector is a 50 ohm threaded connector. The main application of SMA connectors is on components for microwave systems. The connector normally has a frequency range to 18 GHz, but high performance varieties can be used to 26.5 GHz. Frequency Range vs Connector Type
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The SMA connector is comprised of an outer conductor [normally ground] and an inner conductor which normally carries the signal. An SMA connector is used with a Coax Cable 'Manufacturers'
The BNC Connector is a similar style connector, but larger.

SMA to BNC Adapter
SMA connectors contain all the same cable connection styles as any other connector series. Two of the most notable connector styles are shown here. The third a Printed Wiring Board [PWB] is missing. The graphic above shows a SMA to BNC adaptor.
While an SMA Gender Changer is shown below, or SMA Jack to SMA Plug.

SMA Gender Changer
More importantly the version shown above is also called a Connector Saver. A Connector Saver is used to attached [once] to a device under development or test, which then handles the multiple connection/disconnection that occur during the test phase. That way the connector-saver sustains the reduction in service life, while the original connector only sees one connection/disconnection. Recall that a connector will only reliable function under some predetermined interconnections.
Refer here for Coax Connector Manufacturers









