Probably not much, you're only a very small percentage outside the calibrated
range for that slug. That assumes that the slug is ok (not dropped, etc).
You can check them several ways. I use a calibrated attenuator after the meter
with an hp 436a power meter after that (with the appropriate head). Then just
check the slug at several frequencies throughout the range And make sure the
bird and hp meters agree within the stated 5% accuracy of the slug.
You can also use an oscilloscope after the attenuator but you'll need to
calculate the power from the displayed voltage on the 'scope that way. Note
that you can't just use the 'scope without the attenuator to do this -- the
attenuator (assuming a 30db unit) provides the 50 ohm load needed by the bird
meter and the transmitter.
You can get used attenuators inexpensively. For short duty cycle measurements
you can get by with an attenuator rated at much less than your full output
power. Just make sure you don't overheat the attenuator when testing. Optimally
you should check the attenuator for accuracy, but they're usually ok in the
larger sizes (which are hard to burn up :-). You can do a rough check with an
ohmmeter too.
Sent from my iPhone
On Nov 27, 2014, at 6:36 AM, "Clive GM3POI" <gm3poi2@btinternet.com> wrote:
> Hi All, With the wealth of knowledge on here I thought I would ask this one.
> Can anyone put a figure on the displayed power using typical Bird 43
> elements for 2-30mhz when used at 1.83.
>
> My logical guess would be about -5% but have no idea really. 73 Clive GM3POI
>
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