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I am attaching a photo of what I have done.

This hole is not suited there, but how much it is going to affect the performance of the antenna?

enter image description here

JRE
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dharmikP
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    I would be more worried about the screw your are going to use. What material are you planning? – user24368 Nov 17 '21 at 11:11
  • I have to use it for mechanical assembly via stainless steel (SS) screw. – dharmikP Nov 17 '21 at 12:35
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    Anything metal will interfere with the antenna. So it's not the hole you should be worried about. It's the screw. (Also the hole if you plan to have it plated because the plating would be metal) – slebetman Nov 18 '21 at 10:52

2 Answers2

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If the hole is empty and is not metalized, then it won't affect the performance of your antenna.

If the hole is meant for mechanical fixing, use plastic screws.

Metal screws might de-tune your antenna.

A small metal screw won't affect much the overall performance of your RF system.

What de-tunes antennas are walls or big objects.

If your product is wall mounted than the wall will certanly de-tune your antenna a certain amount.

Enrico Migliore
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  • I have to use it for mechanical assembly via stainless steel (SS) screw. – dharmikP Nov 17 '21 at 12:35
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    Use a small screw then. – Enrico Migliore Nov 17 '21 at 12:58
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    I second the plastic or nylon screw for this spot. Metal in this area will detune the antenna and reduce range. In fact, I'd be willing to bet that the screw head will be directly over the trace. – Aaron Nov 17 '21 at 14:38
  • Without knowing the first thing about the rest of the assembly, could this be a plastic pin or hook built into the moulding, cutting down on the number of screws to be inserted as well as not causing antenna problems? – Chris H Nov 18 '21 at 16:13
  • I edited my previous answer. – Enrico Migliore Nov 18 '21 at 16:34
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Heat staking the PCB to the chassis or plastic screws for sure. The steel will induce (attract) the magnetic field to some degree. Even "non-magnetic" stainless steel alloys can be somewhat magnetic depending on how the screw was formed because work-hardening and/or thread-cutting can change the magnetic properties on alloys like 316SS.

GT Electronics
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  • I may be off-base here, but I don't think whether it's magnetic or not has much of an effect. I think it's significantly more concerning that the screw is electromagnetically conductive at the frequency (I'm guessin 900MHZ-2.4GHz) that is being used. Even some plastics would cause issues – Brydon Gibson Nov 18 '21 at 17:49