Signal issues

[retrohss]

I have a phone with dual SIM.

SIM slot 1 is Business EE SIM

SIM slot 2 is consumer PAYG EE SIM

SIM 1 is almost always showing 1 or 2 bars, whereas SIM 2 is showing 4-5 bars, and always better than SIM 1.

Been in to EE shop and this is not to be expected.

Have a replacement SIM and the situation is exactly the same as before.

Conclusion?  EE Business is the problem.

[bristolian]

This appears to be a classic example of where the onscreen signal bars are a very crude measurement, and further investigations would be needed. For starters, try swapping the SIMs between slots to prove that there's "something" going on.

If confirmed, then comparisons of the active radio technology and carriers-in-use would be a good place to start.

[Matt_124]

Signal Bars are quite a poor measurement of actual performance. Your device can perform better with 1 Bar in one location than in another location with 4 Bars. I regularly experience 1 Bar of 5G connectivity but I am connecting to multiple carrier signals and receiving download speeds in excess of 200 Mbps with no performance impact as a result of my on-screen bars.

Is the EE Business SIM connecting to 4G or 5G? 5G is not available on a Pay As You Go SIM, so your comparison may not be apples-to-apples here. Are you experiencing any dropouts or slow-downs on your EE Business SIM that are not experienced on your Pay As You Go SIM?

[retrohss]

I have both SIMs in the same phone.  The phone is 4G not 5G, so one would assume that SIM 1, the business SIM is using 4G in the same way as the PAYG SIM.

I can only assume they are using different networks?

In use the bars to demonstrate that if both SIMs were working in the same way, that the bars would be the same on both.  Equally bad or equally good, but they are not.

The download time on each SIM is significantly different too.

Anyway, the SIM is now back in my replaced iPhone 12 and the signal is poor again.

I am getting 66Mbps Download and 2.28Mbps Upload, on 5G.  I get exactly the same on 4G, in fact I get slightly better download of 72Mbps.  Upload is woeful... 0.47Mbps.

I am in an area that EE say is Great Outdoor and Good indoor for 5G, and excellent in and out for 4G despite me rarely being able to make a call when indoors.

[bristolian]

4G radio doesn't operate in the simplistic way you allude to. 4G coverage is provided by combinations of 4 different frequency bands, each with their own characteristics.

Low-bands will give better wide area coverage and will look better onscreen, but at the expense of performance. High-bands won't give as many onscreen bars but will give much better speeds. The vast majority of radio sites operate a combination of different bands, it's entirely normal for two phones (or in your case two SIMs) to be connected to different coverage layers and thus display different bars.

It's impossible to extrapolate anything from onscreen bars, other than whether you have coverage or not.