April 23, 2023
Losses in coax types, connectors and adapters, taking the mystery out of the "DB"
This past week I had the pleasure of repairing a damaged SMA connector on a portable.
This brought to mind how this could have been prevented with a bit of foresight as to the adapter that had been used to attach his external antenna coax.
We are going to go over a few details concerning the different coaxes normally used by ham radio operators.
Which are good for our particular installation and which is better or worse…and why.
Coaxes normally used by hams. . .
RG-58 A/U loss at 100ft @ 400Mhz is 12.4db, manufacturer specifies use for low power FM.
A little history on the SMA . . .
When the SMA female circuit board connector was first introduced, it was used as a means to interconnect RF cables to circuit boards inside of an electronic device.
It wasn’t until several decades later that Japanese and Chinese radio manufacturers started to use them as an external antenna connector, mainly because it was small and cheap.
This connector was never designed to handle the lateral forces that can occur when an adapter with coax is attached and then bumped fro experiences forces on such a small foot print.
DE WB6AMT Earl
Losses in coax types, connectors and adapters, taking the mystery out of the "DB"