Fourth generation iPhone. Repair is straightforward, but the front glass and LCD must be replaced as a unit. GSM / 8, 16, or 32 GB capacity / Model A1332 / Black and White.

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Is it safe to bridge blue coil inductor

I am wanting to know if bridging the blue inductor coil on an iPhone 4 has any effect on the transmission power of the phone?

This component preamplifies the signal, so by rights it would decrease the signal if anything?

I just don't know the engineering design as to why this component is needed if bridging doesn't affect the signal; as I have bridged an iPhone 4, and cannot fault the signal strength.

If someone could explain this components function it would be appreciated.

Also just left hand side of the battery connector, there is two solder dots; according to the schematics there should be a capacitor there but I have never seen a capacitor on any of the iPhone 4 I have repaired.

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Usually inductors are used to tune the antenna, or optimize its performance. Bridging the inductor in this case should technically de-tune the antenna and cause significantly lower efficiency, but in your case it seems like that decrease is not particularly significant. Perhaps you are not using the antenna that is connected to the coil at the moment?

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Thanks for replying.

I thought it would have decreased its efficiency as well, but it appears to be working.

What I have done is I have since purchased a blue inductor coil, and soldered it on okay.

I know they are an inductor coil so meauring for ohms is probably not going to be accurate, but another iPhone 4 I tested from capacitor to antenna connection is 3.4ohms, where the iPhone 4 I have repaired is 1.5ohms. I am not sure if that means anything?


I'd be inclined to think that the resistance has more to do with the coil's thickness. With that said, for the same physical size, often, inductors with more coils will have a higher resistance, and higher inductance.


The phone is working okay with the coil replaced, and signal is fine.

I appreciate your replies, and thank you.


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Jim Propert will be eternally grateful.
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