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iP4 Antenna Issue and Contact Points

keyofnight

keyofnight

macrumors regular
Original poster
Mar 19, 2009
201
46
Seattle, WA, USA.
I understand this is probably one more in a series of too many iPhone 4 Death Grip issue threads, but I still have a question.

Look at the following picture captured from Steve's keynote:

v3gcol.jpg


The two antennae are separated at two of the three insulated black points: one the lower-lefthand corner, and another in the upper-lefthand corner (next to the headphone jack and second mic). The third black separator is purely cosmetic it seems.

I can reproduce the antenna issue by touching my finger to the lower-lefthand corner, but I cannot reproduce the issue by touching the upper-lefthand corner. If these are the two possible contact points for the two antennae, then why can I only reproduce the problem with the lower-lefthand corner?

I've tried to reproduce the problem with the upper corner, but it just won't happen.

Also, when the bars drop I only have a 75% chance of having some sort of network problem. What that means is: when the bars drop to 1, it usually drops my internet connection to 300Kbit (instead of the usual zippy 1.5-2.2Mbit I get in my house). Sometimes, however, the connection stays the same.

At this point, I'm not upset with the phone—I love this phone. I'm just curious as to what the problem is because it's weird and I'm interested. Excuse the language, but can someone tell me what the hell is going on? (;
 
Not all points on an antenna are electrically the same. It's as simple as that.
 
i'll see if i can give this a shot.

antenna's work by being, in length, as long as or a portion of the wavelength of the signal the antenna is giving off. say, for example, an antenna gives off a radio signal with a wavelength of 1 inch, then the antenna must be, in length, one inch or equally divided. interfering with the antenna at one point, disrupts the wavelength at that specific point in the wave. interfering with the same antenna at a different point, creates an entirely different form of interference, because the wavelength has changed (because the interfering point has changed). something like that.

i'm not entirely an engineer, but that's the easiest way i can explain it. just a heads up, it's not entirely physically accurate, i just chose a couple examples that would make things as easy to explain as possible.
 
sam011989 said:
i'll see if i can give this a shot.

antenna's work by being, in length, as long as or a portion of the wavelength of the signal the antenna is giving off. say, for example, an antenna gives off a radio signal with a wavelength of 1 inch, then the antenna must be, in length, one inch or equally divided. interfering with the antenna at one point, disrupts the wavelength at that specific point in the wave. interfering with the same antenna at a different point, creates an entirely different form of interference, because the wavelength has changed (because the interfering point has changed). something like that.

i'm not entirely an engineer, but that's the easiest way i can explain it. just a heads up, it's not entirely physically accurate, i just chose a couple examples that would make things as easy to explain as possible.
Click to expand...

Thank you for the explanation! I, however, am not convinced this is the answer to my question. Does this mean that interrupting one end of both antennae is not equal to interrupting the equal but opposite sides of those antennae?
 
keyofnight said:
Thank you for the explanation! I, however, am not convinced this is the answer to my question. Does this mean that interrupting one end of both antennae is not equal to interrupting the equal but opposite sides of those antennae?
Click to expand...

I'd assume it has something to do with +/- contacts, but hell if I know.
 
keyofnight said:
lol. This problem is really bugging me, but I guess we'll never know.
Click to expand...

well it's kinda hard to explain because you're asking to be taught, in a forum, what takes about 6 years of college to understand.

but yes, interfering with one end of the antenna is not the same as interfering with the other end although the same length. reason being, they're not actually the same "length" because only 1 end is connected to a transmitter/receiver, the other end hangs freely. so, touching the end that is connected to the transmitter/receiver will cause interference because where you "shorted" the antenna is not long enough to pass a wavelength....interfering with the other end though is long enough to pass a wavelength. hence, why one end works, the other doesn't.

remember, this isn't entirely physically accurate. if you truly want to understand why, get a masters in radio communications, part of the computer and electrical engineering department.
 
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