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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iPhone 4 antenna experiment anyone?

I've already asked this in the http://meta.ifixit.com/ section, but in case more, or other, people check in here at the Answers section (and because this could be considered a repair question), I'd like to post it here too:

It would be nice if someone could do this experiment that might answer some questions about the iPhone 4 antenna's lower left side's no-touch zone problem, or maybe even fix it: since touching the gap between the two antennas at the top of the phone doesn't cause signal loss, move the wire that connects the logic board to the left-side Bluetooth etc. antenna, to the other end of that antenna at the top of the phone, and then test whether touching the left-side no-touch zone still messes with cellphone reception, or if this moves the no-touch zone to the top of the phone, which almost nobody touches while making a call. If cellphone reception still works when the phone is rewired like this, and the left-side gap is no longer a no-touch zone, then you'd want to test the rewired phone in locations that have low ATT signal strength, to see whether the signal strength that gets into the phone is still comparable to the pre-rewired, hold-it-like-Jobs-says state.

Update July 24 2010: It turns out that the wire running above the speaker assembly, that I thought was connecting the logic board to the bottom end of the Bluetooth/wifi/GPS antenna (the longer antenna), is actually connecting the logic board to the bottom end of the cellphone antenna. I made my initial judgement based on looking at the ifixit teardown photos, which aren't clear at the antenna connections. TechRepublic's teardown photos (http://content.techrepublic.com.com/2346...) make clear the only logic board connection at the sensitive gap is to the cellphone antenna. TechRepublic's photos don't show any detail for the upper gap's connections, though presumably the upper end of the Bluetooth etc. antenna connects to the logic board at the upper gap. This probably makes rewiring the ends of each antenna unworkable, since the only other possibility I can think of, moving the cellphone antenna's connection from the lefthand gap to the upper gap, would probably drastically negatively affect the cellphone antenna's performance. Moving the Bluetooth etc. antenna's connection from the top gap to the left-side gap, while leaving the cellphone antenna's connection at the left-side gap, would probably make the left-side gap even more sensitive, dropping even more cellphone signal when touched.

All this probably makes coating the sensitive antenna gap the next-best thing to do, short of putting the iPhone 4 into a case, which is even better, not just because it protects the phone, but because it eliminates hand contact with any part of the exposed metal antenna, resulting in even less signal drop than just coating the sensitive gap to prevent one's hand from touching it.

Answer this question I have this problem too

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Why don't you try it?

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Majesty: I would if I had an iPhone 4! Which I'd have if I could afford it. Until then, I'm currently using my old iPhone "2G", which is working fine for me.

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this probably won't work. Antenna's need to have a specific length to receive certain frequency's. If you change the connections from the BT antenna with the GSM antenna, you might solve signal drops by touching the antenna. But you'll probably have bad reception at all times.

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Benjamin: I'm not suggesting swapping the connections from the logic board to the two antennas--I realize the antennas need to be a specific length for each set of frequencies that each antenna handles. I'm suggesting changing the logic board's connection to the Bluetooth etc. antenna, from one end of that antenna to the other end. But see my edited comment at the top for my latest finding about how the antennas are actually connected to the logic board, making my initial idea unworkable.

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I have a question regarding the metal rim on the outside. Does anyone know where there is an antenna connection to that outer rim? The only antenna connection I can locate is from the logic board to the normal located at the bottom antenna. I have an iPhone 4 completely apart and there are no connections directly made to that outer rim from any RF sections of the logic board (WiFi, GPS, Cellular, etc).

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