I am looking to purchase a low noise amplifier for a center frequency of 435 MHz with the goal of attaching a UHF (70cm) antenna to the LNA. However, while searching for available options, I realized that there is a significant price gap between websites. Currently residing in Germany, I find myself with limited options. What could be the reason for such a wide price range, and what details should I pay attention to?
For instance, there is one priced at 109 € available at TGN Technology Online, another at 10 € from ElecBee, another at 140 € from Wimo, and a fourth at 43 € from Grandado, and finally, one priced at 9 € on Amazon.
I wanna know why there’s such a big price difference between these amps and what stuff I should pay attention to when picking one. Any ideas?
The amplifiers themself are not the pricey part, the rest of the design is (:
Wide band means that any strong out of band signals will also get amplified, strong enough signals will absolutely ruin the signals of interest.
All filters have losses, all amplifiers have have noise figures. Depending on what you are doing and how the RF environment at your site looks like then plays a big part in possible solutions.
For example, I use a small QFH for 70cm and that just has a LNA4ALL (wide band) directly at the top feed point, I can get away with that because the antenna is not picking up the ~100MHz broadcast FM and other very strong sources locally.
The list you posted include at least one (TGN) that has filtering before and after the LNA, most of them is without filtering before or after the amp. Additionally there’s SAW filtered ones and band pass filtered. All of these have different compromises and prices.