by ericmark »
Sat Mar 28, 2020 11:16 am
As @Mr White said, aerials are complex, it does not really matter what frequency the same principals are valid, but as the frequency goes up effects are more marked.
We would see phrases like correctly terminated, and this did not simple mean ensure screws tight, it refers to matching the impedance, also length of cable, I remember with a 2 meter wave length thinking I would tidy up cables by cutting off the extra, and had to make up new cables as my signal strength was reduced.
However with my hobby there were meters both built into radio and after radio which could measure power out, power in, and most important power reflected back into the radio.
If the leads are connect lengths and all it tuned correctly 100% of the signal will be transmitted, but if not some of the power is reflected into the radio which can cause over heating and cause components to fail, the CB guys called is SWR stands for standing wave ratio, which is the percentage of signal transmitted compared with signal reflected.
The meter for high frequency was not too expensive, but as the frequency goes up so does the price and also the leads used to connect it mean it becomes inaccurate and instead of wire pipes are used, some radio hams do play with micro waves, but the maths is beyond my ken.
So mobile phone frequency is not simply one, and where using multiple frequencies it gets really complex, even with a site hand held radio if the rubber cap was knocked off the stub aerial that was enough to cause the radio to interfere with other site radios, and become deaf.
There may be a car kit you can use, but it would likely be easier to move the whole radio.