Hi John, What did you use as the P3 bandwidth for your noise measurement? And conversion to 1Hz equivalent. The P3 has its own bandwidth and is not affected by setting the receiver bandwidth. Lee K7T
Author: John Kaufmann via Topband <topband@contesting.com>
Date: Thu, 25 Feb 2021 17:29:51 -0500
The P3 noise measurement bandwidth was about 100 Hz in my measurements. Quoting from the P3 user's manual, "the effective bandwidth of the P3 is generally one display pixel, which is approximately sp
On 2/25/2021 2:29 PM, John Kaufmann via Topband wrote: The P3 noise measurement bandwidth was about 100 Hz in my measurements. I hope that everyone realizes that setting a high value for averaging ca
Author: John Kaufmann via Topband <topband@contesting.com>
Date: Thu, 25 Feb 2021 20:16:06 -0500
The P3 averages power, not amplitude, so using longer averaging times just smooths the display and doesn't reduce random noise. John W1FV --Original Message-- From: Topband [mailto:topband-bounces+jo
It has nothing to do with power. Last I looked, the P3 is reading and displaying the instantaneous voltage in the IF, and can be calibrated to voltage at the input. I've been doing swept measurements
Hi Jim, Its funny that you brought up this topic as yesterday when I was doing comparisons of the signal I could hear on my 160 meter vertical TX antenna versus my portable flag, I increased the aver
Hi Jim and gang, I would like to make one minor correction and then add some more info. On my SDR receiver I should have said I increased averaging from 1 to 10 in my previous post (not 2 to 10) and
Author: John Kaufmann via Topband <topband@contesting.com>
Date: Fri, 26 Feb 2021 10:31:10 -0500
I think there may be some semantic confusion over the term "averaging" and how averaging affects noise when making spectral measurements, so let me clarify what I mean. My comments are specific to th
Averaging is a nice technique that mitigates the poor sensitivity of the mini-flag, but only for "bright lines" due to power supplies, etc. I would be surprised if it would do anything to improve DF'
Hi Jim, From the P3 manual:/ / /"The dsPIC further processes the signal for presentation on the 480x272-pixel color TFT LCD display. The "circuitry" shown inside the processor box in the block diagra
Hi Rick, This next piece of info is not really related, but here is another data point for folks since you mentioned using an AM radio with built in bar antenna tuned to 1710 KHz to track down powerl
When dealing with narrowband That's exactly what I said in my first post. The effect of the bandwidth of bins is to increase the frequency resolution (and decrease the time resolution) of a measureme