Would someone please explain...

Question

.....how to determine the actual connection speed my mini is making , via airport with it's chosen base station.?
Thank you
Rebecca.

Answer 1

By the way my network jumps around with the
connection speed from 0 -11-48-56-6-8-11 etc etc
etc(seems to hang around at 11Mbps most of the
time)but shows 4 or 5 arcs in the airport display(top
right of desktop)
-what does this mean to me for downloading browsing
etc?.
The practical effect is that browsing will generally be slower than it otherwise could be, and downloads/file transfers will vary in speed to some extent.
I understand that various other sources of
interference such as microwaves, mobile phones etc
can affect the signal strength but if none of these
are present one should get a stronger more reliable
signal, correct?
There are many forms of potential interference and causes of signal degradation for radio signals at this frequency, and not all of them are obvious ones. There could, for example, be another wifi in range which is not broadcasting it's SSID but occupies the same or an adjacent channel. It's also possible that your wifi is actually interfering with itself through something called 'multipath'. This is present to some extent with all radio signals, and is caused by some of the signal traveling a direct path between transmitter and antenna and some bouncing off structures and surfaces, thus reaching the antenna slightly later. If this happened with a TV signal you'd generally see ghosting on screen, but with radio it causes noise, which doesn't degrade the signal strength but does reduce the readability of the signal.
RF (radio frequency) noise can also be caused by local appliances such as TVs, many of which tend to radiate rather broadband garbage which can affect radio reception in the immediate vicinity. Fluorescent lights (including some of the low-energy bulbs available today) also create RF noise, as do many motors used in ceiling fans and the like. Often the actual level of noise being received at the antenna will be affected significantly by the movement of people and animals, and if the source is a nearby TV, it can also vary depending on which channel is being viewed and how bright/contrasty the picture!
A high signal strength reading coupled with slow data transfer rates tends to suggest that it is most likely you are suffering RF noise. You may be able to reduce the impact this noise has on your wifi by adjusting the angle of the antenna (if your base station has an external one that can be moved), and/or by changing the operating channel. You can also test potential sources by switching them off (some TVs and other electronics may need to be unplugged since in standby mode they can still generate RF noise).
Ultimately, however, the worst source of spurious and unwanted radio noise capable of interfering across the radio spectrum is the computer itself, and if the lead from the antenna inside the mini to the airport subsystem is not fully connected or properly screened, you can suffer considerable wifi degradation. You can test for this by moving the mini and base station together. In doing so you have to be cautious that you're not desensitizing one device with the other, so make sure the signal strength shows full, then test your connection speed - if it still varies wildly, you likely have at least some issue with RF noise inside the mini itself, affecting the airport antenna.