what is a good amplifire design for 3G ( I have a vodafone 3g datacard (merlin 360) and I am in a marginal area, I need an amp that will give me about 6db of gain but I don't know what device to use to amplifie 2.1 ghz...any sugestions?)
You don't want to be trying to design and build a micro-wave bi-directional amplifier - you're looking at EXTREMELY difficult design and construction problems.
If you can find one to buy?, I suggest you do that, although adding an external aerial (at a decent height) may be all you need?.
O.k so if I were to extent my existing aerial, what would be the best design, can I use a yagi? or a dish? the aerial that comes with the card has only a 2 ft long lead. I get about 3db gain with this but it is not enough. any sugestons as to what aerial would be best?
O.k so if I were to extent my existing aerial, what would be the best design, can I use a yagi? or a dish? the aerial that comes with the card has only a 2 ft long lead. I get about 3db gain with this but it is not enough. any sugestons as to what aerial would be best?
Again, I would suggest buying an aerial, or (for a start) buying an extension lead - and getting the existing aerial in a better place, which may be higher, but may not be. Fitting a better aerial in the existing site will only make the difference of the increase in gain between the aerials - better siting may well make a LOT more difference.
A cantenna design might work, the websites usually include the ability to alter the frequency required in the design **broken link removed**
And at around $20 to make one it can't hurt the hip pocket to try one.