Gareth Magennis wrote:

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Well a piece of wire worked a treat.

With a bit of heatshrink for strain relief at the transmitter end and
another on the end of the tail, it even looks like a proper one.



** So now you know how to make a "rat tail" antenna.


Thanks to all for the calculations and info.


** 300 / MHz = wavelength in metres, is worth remembering.


FYI:

That AG-1 unit is about as basic as UHF FM links get, so has limited useful
range and is prone to signal drops out due to multipath interference. The Tx
signal can almost cancel itself after reflecting off objects and surfaces
and then arriving at the Rx.

Better models have twin channel receivers, with two separated antennas,
operating as a diversity pair that helps greatly to eliminate such drop
outs.



Presumably the transmitter antenna should be straight for best efficiency.

If it is (worst case scenario) a semicircle, what changes?


** Every effort should be made to straighten it !

It's an FM signal, so the recovered audio is not affected until the RF level becomes very weak. Meaning there is usually plenty in reserve to allow for circumstances that reduce the RF level compared to free field.

Players buy units like this not to get long range, but merely to be free of that damn instrument cable.


..... Phil