How to fix your iphone if it is broken

First you need some tools.

These you can order from here.
1. http://www.24.se/iphone-lcd-sugpropps-oppnare-p-15102-c-1136.aspx

2. Second you might need a knife like this video

3. Order parts from same shop as above link here

Watch this video while you try same things.

iPhone 3GS Complete Screen Replacement Directions by DirectFix.com 

 

How to Replace Your iPhone 3G or 3GS Battery 

Video here

 How To: iPhone 3G/3GS Dock Connector Replacement 

Video here

Antenna problem ?

This is something that is with connector 7. This is not an fix for doing by yourself.

Lucky that this company do it.

See here

Why Jailbreak iPhone

Maybe this link can give you the answer.

Boost you antenna signal -

i-Tena 3G Signal Booster Review

Video here

 There is also this solution

 CellRanger – the answer to IPhone 3G signal woes?