Hi guys, 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. I'd suggest a pigtail SMA to BNC for connecting to a coax for mobile use (even then I tie the pigtail to the HT case with a rubber band or ??) As for the HT antenna all you can do is be careful or brace the antenna a bit. My 74 year old hands and eyes had quite a time repairing the broken center conductor to circuit board, not to mention just getting to the location. The SMA is a great RF connector for fixed-in-place applications. Nuff said
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.
I'd suggest a pigtail SMA to BNC for connecting to a coax for mobile use (even then I tie the pigtail to the HT case with a rubber band or ??)
In the past, I'd use this suggestion whenever I wanted to use an AL-800 (or similar large) telescoping whip with an HT that had an SMA connector. Now I use a short coax jumper with BNCs onto the adapters on my HTs. Once I put those Diamond adapters on my TH-D72A and TH-F6A, I don't remove them.
As for the HT antenna all you can do is be careful or brace the antenna a bit. My 74 year old hands and eyes had quite a time repairing the broken center conductor to circuit board, not to mention just getting to the location. The SMA is a great RF connector for fixed-in-place applications.
Agreed.
I don't think anyone is questioning whether the SMA is a good RF connector. Its use on our ham HTs has been questioned for a long time. I see other connectors used on non-ham HTs. I have a few commercial Icom VHF and UHF HTs that are in this non-SMA group. Why not consider those for our HTs? SMA connectors are smaller, which is probably the big point for their use with our HTs, but certainly not rugged.
73!
Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/
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.
participants (3)
-
Greg D -
JHBRTOO＠aol.com -
Patrick STODDARD (WD9EWK/VA7EWK)