Gudguyham@aol.com wrote:
>
> In a message dated 3/7/2006 6:38:36 A.M. Eastern Standard Time,
> ka1xo@juno.com writes:
>
> There are many different RF Power wattmeters, but the Bird 43
> with a 5 or 10KW slug connected in-line to the nearby antenna
> is the hands-down final say of True Power in that group.
>
>
>
>
> In my circle of HAMS (not CBer's) we call the "Bird wattmeter watts" THE
> GOSPEL!
>
> It is our standard by which we honor the "Golden Brick Award:" of which I
> have held for some years now. It is the only standard by which the award
> can
> be obtained. We actually have a committee armed with a BIRD wattmeter and
> BIRD dummy load who do the testing.
>
> Nuff said. Hi Hi 73 Louie W1QJ
Don't worship the Bird.
The Bird 43's I was testing twenty years ago were rarely within 5% of
FSD. Most were within 10% of FSD, but still a significant fraction were
outside of that. (These measurements were made at a government standards
laboratory.)
Bird 43's are fine for determining if a PA is working, but they are not
capable of accurate power measurement.
I had a Bird 43 myself and bought a new element that covered 432 MHz. It
was out of spec the day I got it. I returned it to the UK dealer (Aspen
Electronics), who adjusted it while I was there to be right at 432 MHz.
I then checked it again, and it was indeed then within spec at that one
frequency.
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