What is an RF Isolator?

[itsgalf]

Hello all.

I recently received my brother's old Surface Pro 3 because his screen had become cracked and unusable. He did not want to attempt a replacement so I told him I would take it.

Well I bought a new screen from ebay and replaced the screen - The disassembly didn't go so smoothly I ended up just chipping the screen around the perimeter and eventually got it off. The one casualty in the disassembly is on the front-facing camera and antenna trim. It's labeled RF Isolation.

Now I could buy a new trim off of ebay (now listed at $45). But the SPro3 seems to be working just fine without it. Last step would be to put the adhesive on the screen and put it in place.

What is an RF Isolator and do I really need it?

 

[GreyFox7]

RF Isolators - everything RF.

RF Isolators

An RF Isolator is a two port device that protects RF components in a system from excessive signal reflection. It is a non-reciprocal device that ensures that all the power is transmitted from port 1 to port 2, while isolating absorbing/isolating any power incident at port 2. An isolator is often placed at the in front of sensitive component sin the Rx/Tx chain to avoid unwanted signals from damaging sensitive components.

Note by casual observer: A two port device with 3 ports

You probably need it unless you can avoid unwanted signals whenever you want to.

 

[itsgalf]

Thanks for the reply.

So without it the (sensitive) components are more likely to get damaged from unwanted radio frequencies?

Darn, I was hoping not to have to spend more money on this repair. But maybe ~$210 total for getting this SPro3 back up and running isn't too bad.

 

[Wayne Orwig]

In this case, I suspect the RF isolator is just some plastic or foam. The point of it is to simple keep the antenna away from the metal, which would detune the antenna, or reflect or absorb the RF energy. If there is still plastic/foam/tape keeping the antenna in the same general area, an it is working fine, you are good to go.

A photo of the damaged piece would help a lot.

 

[itsgalf]

hmm well it has a label on it with RF Isolation

Here's a picture of it (attached)

It's located on this trim piece: Microsoft Surface Pro 3 1631 Front Facing Web Camera + Antenna X898337-001 Trim | eBay
The front part of that trim can be seen on this pic from ifixit's breakdown guide: https://d3nevzfk7ii3be.cloudfront.net/igi/Iq2RPBi1wDESblgv.huge

 

[Ania J.]

Hey itsgalf! How are you? I have just changed the screen on SPro3 and run into the same issue as you, I slightly damaged RF Insulator, see pictures attached. I was wondering what you ended up doing? Did you leave it as is and is the machine working good, or did you buy the antenna part? Thanks so much for your help in advance.

 

[Ania J.]

In this case, I suspect the RF isolator is just some plastic or foam. The point of it is to simple keep the antenna away from the metal, which would detune the antenna, or reflect or absorb the RF energy. If there is still plastic/foam/tape keeping the antenna in the same general area, an it is working fine, you are good to go.

A photo of the damaged piece would help a lot.

Hey hey Wayne Orwig, thank you so much for helping us here! I have just changed the screen on Microsoft Surface Pro3 and I have the same issue as itsgalf . I am attaching the photo of the damaged part --- RF Isolator. Do you think I should buy a new part? Or would this work? Many thanks. Best wishes.