Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange
Join us in building a kind, collaborative learning community via our updated Code of Conduct.

Questions about sunspots, how they are measured, what those measurements mean and how they affect amateur radio activity.

14
votes
4answers
3k views

What is the cause of this unusually long period of terrible HF band conditions?

I've been a ham for over 40 years, but never has there been such a prolonged period of such poor propagation. This has been especially the case over the past six months or so, and they continue to ...
6
votes
2answers
4k views

Where year 2018 falls in the sun spot cycle for HF propagation?

Are we now at the good or bad portion of the 11 years cycle? What effect are we seeing now? How large (strong/deep) is the effect during the peak and bottom of cycle? What will change in coming years?
3
votes
0answers
71 views

Calculating effective SSN (sunspot number)?

I am doing research on how SSN-like parameters affect HF radio signals. As I can see, effective SSN is a parameter that is derived from SSN or using other parameters. Does anyone know how to calculate ...
7
votes
2answers
373 views

How do sunspot numbers (SSN) affect radio operations?

I frequently hear talk about SSNs in Amateur Radio, and somehow if the number is high, that's a good thing. I just don't really understand what they are, and what they mean, and I'd like to better ...
13
votes
2answers
747 views

Why is the solar-flux index measured at 10.7 cm?

Why is the solar-flux index measured at 10.7 cm? What makes that such a special frequency?
4
votes
3answers
4k views

How and why sunspots affect propagation in HF bands?

How and why do sunspots affect propagation in HF bands?