It is worth noting that your calculation of power is missing a divide
by 2, since you specify a peak-to-peak voltage, and not a peak
voltage. The equation for peak-to-peak voltage to power (given a 50
ohm impedance) is P (watts) = (.707*V/2)^2/50, which when I calculated
yields something like .61 mw, so this is correct.
Also, as far as I am aware, the BasicTX board directly accessing the TX
output of the AD9862 chip, so perhaps your best bet is to check the
datasheet for this IC. This should yield a power output versus
frequency. The alternative is to measure yourself, as you have done.
Remember, the datasheet is only a reference. Actuall power levels can
vary within a tolerance (which the datasheet should also provide) due
to variations in gain and/or biasing, connector loss, transmission line
loss, impedance mismatch, and so on.
~Jeff
On 6/25/2010 12:44 PM, William Cox wrote:
Sorry for the bump, but I'm confused about the output
power of the BasicTX, especially in regards to 1 channel or both.
Any thoughts?
William
On Mon, Jun 21, 2010 at 10:46 AM, William
Cox <address@hidden> wrote:
I'm
getting conflicting info on how much power the BasicTX can transmit.
Ettus FAQ says, "Yes, the BasicTX will
put out about 1mW up to about 50 MHz."
When I
use "usrp_siggen.py" with full amplitude, my sineway has a peak-to-peak
voltage of nearly 500mV -> (0.707*0.5V)^2/50ohm = 2.5mW
So, which
should I go by? I'm trying to find an amplifier that will take my
signal up to 200mW to go into a laser bias-T.
Thanks.
-William
--
~Jeffrey Lambert, K1VZX
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