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Much of my professional life has been with radios being operated by the government and in the US, anyway, the military (and government generally) is most certainly subject to spectrum regulations both

And Alex Morris is now at MIT Lincoln Lab, so he's still fooling with radios.. There has been a variety of programs sponsored by the US DoD for very low power ionosondes (that SwRI Part 5 application

Precisely that - the regulatory authorities make exceptions for "useful" stuff that doesn't "significantly interfere"? with other services. I'll bet if you dig into the international Radio

Folks, I appreciate all the ideas being floated here but let's keep the the original question of a waterfall mode on the NanVNA.? At this time, it's been suggested that a waterfall mode may be useful

Why not get familiar with the software produced by G3PLX, I think it was called Chirp, which used the existing sounder…..this would prevent the pollution of extra transmissions. > >

Besides researchers, the prime users (i.e. military) are not usually subject to national or international spectral regulation. For the most part, they usually comply, both to avoid possible push-back

Hi Donald and David and group, Basically, I agree with all that you say. But take a peek at: https://scholarworks.alaska.edu/handle/11122/4535 and note the power used. Over the years, the approach to

One thing that has always puzzled me about the ionosonde scans is how they "get away" with plowing through wide swaths of the HF spectrum, seemingly with no regard for the fixed frequency users of

I found a very thorough analysis on the mated SO-239 and PL-259 pair from W0QE. https://www.w0qe.com/Technical_Topics/uhf_connector_compensation.html The analysis shows a discontinuity of 1.03" with

Hello Brian. The link takes you to the paper. I would not bother trying to link to the figures or table. They no doubt are not present any longer. The artwork belongs to the publication. So nothing I

Yes, Terry has many archived records stored at a NOAA facility in Boulder that are on film. The original setup is still present in his shack onsite of the present (yes, Didisonde) ionosonde in

The QVI sounders are swept from 2 to 20 MHz in 180 seconds, every 12 minutes (100kHz/second) The WSBI sounders are 5 to 28 in 282 seconds, every 12 minutes. But WSBI has a sort of segmented sweep that

Are these signals modulated in any way? How fast is the sweep? From time to time I notice a carrier on the panadapter sweeping slowly up the band. Just curious whether it’s possible that I’m

I should note that the ionosonde we were using had a transmitter that covered 2 to 30 MHz. It was programmed to skip the WWV frequencies by 100 kHz on either side, and all the ham bands in that range.

I love this thread. I've done some work using WSPR to probe propagation on the 40m band. The advantage to WSPR is a dedicated group of reporters located around the world. By using only 200 mW, it is

We had a vertical incidence ionosonde at one of our field sites when I was in grad school at the University of Illinois. It could be recorded either with a Polaroid camera fastened to an oscilloscope

Especially since it's a digisonde, which transmit pulses, unlike the older chirpsounder. Vertical Incidence Pulsed Ionospheric Radar

I should make one more comment to bring all this into perspective WRT the NANOs. The transmitters necessary to accomplish the (S+N)/N that are shown in the plots require a minimum of 3 kW. Terry's

Ray: The ionospheric sounders with which I am familiar were in the kilowatt to multi-kilowatt power class and were run under experimental licensing. Even if you wanted to use a few watts, I would

The following is a screen capture of the ionosonde (ionogram) located in Boulder, Colorado. I'm located some 40 miles as the crow flies from its location. I also volunteer at Little Thompson