2.6 GHz dual-core Intel Core i5 processor (Turbo Boost up to 3.2 GHz) with 3 MB shared L3 cache.

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Is the Antenna Supposed To Be Short Circuited?

Recently, i accidentally broke a few IPEX headers for the wifi/BT module in my macbook retina. In my attempts to fix the issue without having to spend 60USD for 3 wires, I noticed that all 3 antenna cables are actually shorts (loops). The wires are coaxial ones with a twist ground on the outside and a core for signal, yet on all three wires, my continuity test shows that they are connected. is this normal?

Update (02/21/2017)

Thanks guys for all the info! I've successfully fixed the wifi and now i've got good signal for both 2.4 and 5ghz aswell as bluetooth!

I did it by cutting the coaxial wires and then isolating the shielding and signal lead by cutting the shielding short of the center wire, and then doing the same for a brand new 0.81mm coaxial wire (with a pre-attached connector) and joining the two pieces in a Y-shape by soldering signal to signal and shielding to shielding before heatshrink-insulating the joint(s). <-- Note that you must have ultra-thin heatshrink, i used 1mm heatshrink tubes.

Doing this myself for all three broken connections helped me save quite a bit on repair costs. A reputable repair shop around here (Beijing) gave me an estimate of 60-70 USD (equated), whereas my fix cost me a total of less than 9 USD (equated, including shipping costs).

(EDIT) I guess the estimated repair price is high due to the semi-high possibility of the screen cracking during the bezel removal process required when changing the iSight+Antenna module, so it makes sense I guess.

I used:

- Soldering Iron

- Leaded Solder

- 1mm Heatshrink

- Small Wire Stripper (small scissors will do too)

- 0.81mm IPEX Coaxial wires with pre-crimped connectors (getting the ones crimped on both ends gives you more tries per each wire).

Answered! View the answer I have this problem too

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Chosen Solution

DC short does not equate to RF short. Actually it is common for the feed and ground to be conductive if you probe it.

Below is from a Macbok air, it is obvious that the antennas have common ground and the feed points are wired together. It is not the exact same model but I suspect the design is very similar.

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Thanks for the explanation!

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The coax shield is common across all three, each center wire within the coax is isolated from the other.

You'll need to properly fix your system by replacing the antenna unit.

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Thanks for the info! I took the antenna unit out and inspected it, the multimeter shows all three are connected by the large copper plane. I will be wire-to-wire soldering an extension to each of the coaxial (signal/ground insulated) as a ditch attempt before replacing the unit (in which i will be sacrificing my iSight camera in order to not remove the screen bezel). Will update after i'm through!

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Here's the part you'll need: MacBook Pro Retina A1425 iSight Webcam WiFi Cable 821-1589-B.

I've been lucky desoldering the broken lead from a good antenna unit and threading it though the hinge replacing the damaged lead.

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Thanks guys for all the info! I've successfully fixed the wifi and now i've got good signal for both 2.4 and 5ghz aswell as bluetooth!

I did it by cutting the coaxial wires and then isolating the shielding and signal lead by cutting the shielding short of the center wire, and then doing the same for a brand new 0.81mm coaxial wire (with a pre-attached connector) and joining the two pieces in a Y-shape by soldering signal to signal and shielding to shielding before heatshrink-insulating the joint(s). <-- Note that you must have ultra-thin heatshrink, i used 1mm heatshrink tubes.

Doing this myself for all three broken connections helped me save quite a bit on repair costs. A reputable repair shop around here (Beijing) gave me an estimate of 60-70 USD (equated), whereas my fix cost me a total of less than 9 USD (equated, including shipping costs).

(EDIT) I guess the estimated repair price is high due to the semi-high possibility of the screen cracking during the bezel removal process required when changing the iSight+Antenna module, so it makes sense I guess.

I used:

- Soldering Iron

- Leaded Solder

- 1mm Heatshrink

- Small Wire Stripper (small scissors will do too)

- 0.81mm IPEX Coaxial wires with pre-crimped connectors (getting the ones crimped on both ends gives you more tries per each wire).

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samuelhe8 will be eternally grateful.
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