Quoting IVP <joecolquitt@clear.net.nz>:
> http://www.rfm.com/products/apnotes/antenna.pdf

I had read this, a fantastic primer.

> One of the 'others' is the Linx Splatch
>
> ANT-433-SP_-ND is very nearly as good as an external 1/4 wave
> whip. Range for a 434MHz transmitter said to be 7dBm is 320m
> with a whip, a little over 300m with a Splatch (using a ground plane
> of 38mm x 90mm)

I had also seen this.  However I wasn't sure what sort of propagation =20
pattern it had.

300m is mighty impressive, but if that is completely directional from =20
the board edge then perhaps less useful.

Have you tried a Splatch?  Either that or the short helical =20
recommended by Matt look fine, am just interested in how directional =20
they will be.

I am assuming from their datasheet diagram that the ground plane can =20
just be the whole board ground plane, but you mention 38x90mm =20
specifically?

David
--=20
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