Coaxial Cable Braid Clamp - John Dunn, Consultant, Ambertec, P.E., P.C.

Here is a surprisingly difficult item to find. I need a clamp that can wrap around the braid of an RG-58 coaxial cable and has a tab that can be attached (soldered?) to a PC board. This is the very dickens of a problem! I can't find anything like this in any catalog, at least not yet, even though I remember seeing something like this actually used once upon a time.

Can someone offer a suggestion?

Comments

[John Dunn]

Just to note, the closest thing I could find was a Keystone clamp, Catalog No. 8100. However, this device is made of steel with zinc plating which is a dissimilar metal to the coaxial cable braid and not compatible with the need to solder.

[Dick LaRosa]

John, you must slide a metal cylinder over the insulator and under the braid. Then crimp or somehow squeeze a solder lug over the braid. The insulator is too soft to support the braid.

[Jon Titus]

Take a piece of shim brass and wrap it around the exposed braid much like a metal cable clamp with a tab. (See Google images for examples.) Fold a bit of braid back over the brass, hold the tabs together, and solder. Use the tab to connect to whatever you want. Put a hole into it for a screw or for a solder connection.

[L. Jonathan Kramer, P.E.]

I am assuming the reason to avoid simply removing most of the braid and bending the remainder away from the insulator to solder it to the board is to avoid reflecting the wave in the coax. An easy way to achieve both is to flair the braid away from the coax, put the insulator through a hole in a piece of brass shim stock, put another section of braid over the insulator and flair the braid similarly against the shim stock. the braid can then be soldered to the shim stock on both sides, providing a reflection-free ground connection. The soldered connection of braid to shim stock may need to be circular to avoid impedance change, and waveform preservation into the circuit board will need an engineered solution.