Another $.02 from this neck of the woods...
BNC connectors may generally be more robust than SMA, but BNCs are not totally free from problems. The center pin on my Alinco DJ-580 cracked away from the wire going to the PC board, and the cylinder came loose on its mounting (allowing it to twist), both of which required a deep dive through three layers of PC board for the repair.
On the other hand, I've never had a problem with the SMA connectors on my TH-F6A or D-7AG, which I variously use the original SMA antenna, an extended after-market version, or a non-supported BNC adapter with my Diamond RH-77B. I am aware that SMAs wear out, so I try not to change them often, however.
Greg KO6TH
Patrick STODDARD (WD9EWK/VA7EWK) wrote:
Hi, (name/call?)!
My two cents worth- using an SMA to BNC adaptor does not address the mechanical problem of an antenna or a coax flexing the SMA chassis connector- especially the plastic HTs- I had to do a number on my VX5 which is a metal case HT.
The original two-part SMA-to-BNC adapters had no plastic/rubber cushions to help lessen the stress on the SMA connector. There has been an adapter made by KC2BHO for some time, and now the Diamond adapter I referenced earlier, that have something to help with that. Putting the large AL-800 telescoping whip on these HTs, even with the better SMA-to-BNC adapters, is probably not wise.
For the typical duckie antennas, smaller telescoping whips, or coax - these newer adapters are adequate for most hams. It is still possible to put too much stress on the SMA connector with this adapter and whatever is connected to the adapter.