SMA Connector Torque

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Joined: Thu May 09, 2019 2:59 pm

SMA Connector Torque

Post by G4NRT » Tue Jul 09, 2019 8:39 am

I read somewhere that brass SMA connectors should be tightened to a torque of 3-5ft.lbs.

Do I need to worry about this? Do I need to buy a torque tool?

What do others, with way more experience than I have with these kinds of frequencies, do?

Thanks, David G4NRT

Posts: 222
Joined: Thu Apr 26, 2018 9:36 am

Re: SMA Connector Torque

Post by g4eml » Tue Jul 09, 2019 9:20 am

As with any RF connector too little torque can result in a poor connection and too much torque can damage the connector. SMAs are more likely to being damaged by too much torque due to their small size. Brass connectors are more easily damaged than stainless steel ones.

In a test lab the use of a torque spanner is essential to prevent damage to equipment and to ensure good repeatability of connections.

Whilst it is good practice to also use one for amateur systems many people get away without doing so. Finger tightening SMAs is not likely to over torque them. The recommended torque setting is actually quite light so it is easy to exceed this if you use a standard spanner.

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