Exclude the two factors of "producer" and "operator".

All mainland licensed products have a "network access permit" sticker, indicating that some signal template standards have been debugged or specified. Every brand is different, and the mobile phone without this net sticker has not been debugged by the mainland signal, so the signal strength of the European version of the mobile phone in Chinese mainland is not so great, such as passing through a tunnel or a fully enclosed metal space.

But there is actually a big reason, that is, the manufacturer's factor. For example, there are Malaysian products, European products and China products. Just like cars, Audi and BMW are the same, and the quality of imports is better than that of domestic ones.

Another factor is the operator. Many models are customized by operators, and there are some T-mobile-like signs on them. These phones are like Chinese mainland's signal access permits. They are debugging their own network, and the signal will be unstable when they come to China. The reason is that China has three networks, and only China has one in the world.

Let's start with signal radiation.

Indeed, life experience tells us that the stronger the signal intensity, the stronger the radiation, just like the mobile phone that can receive signals in tunnels and metal circles mentioned above. However, China officials have always denied this, so we have no way to prove it.

In fact, there are no strict requirements for mobile phone production in China, and there is no explicit provision. There is no quantitative regulation for anything in China ... not in Europe and America, but there are regulations for the number of n digits after the decimal point for the signal, radiation and even the content of some metals in mobile phones! ! The best example is a large number of licensed cottage mobile phones in China, whose radiation is three to five times that of European mobile phones. So it led to the purchase of mobile phones in China, and the radiation intensity was really not guaranteed.

However, there is a misunderstanding. The definition of European version of mobile phone lies in the mobile phone issued in Europe, which does not mean that 100% is produced in Europe and America. For example, Apple mobile phones, Apple mobile phones all over the world are produced in Shanghai and Shenzhen! But Apple insiders also know that mobile phones are also approved, the US version is the best, the screen is like this, and so are other components.