Question of propagation and upcoming solar eclipse

Discussion in 'General Technical Questions and Answers' started by W3HMK, Aug 13, 2017.

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  1. W3HMK

    W3HMK Ham Member QRZ Page

    Seems like the right place to post-
    Although relatively new to the ham world; I have been bit BADLY and find myself dreaming of antenna designs and DX. Chance has it that my inlaws house is about 9,000 feet from the geographical centerline of totality for the upcoming eclipse. My interest in astronomy predates my interest in radio so, I naturally found this an advantageous opportunity to combine the two and travel down to witness the spectacle as well as operate my station as much as possible. My question is - How exactly will the eclipse effect propagation? I understand it will improve... possibly... but how? and where? I do not consider myself an "appliance operator" and am fascinated in the technical theory of this hobby.
  2. K6CLS

    K6CLS Ham Member QRZ Page

    Hi, great question. Hopefully you'll get many informative responses here.

    My take is, D layer ionization will disappear quickly and MF like 630m, AM broadcast, 160M and maybe 80m, will propagate nicely. but it's not clear whether those bands will propagate along the line of the eclipse, or perpendicularly. thinking about grey line here...

    Folks are running several different projects to capture hard data about propagation. most people I've spoken with want to be in the path oc totality. but i think the most interesting propagation will be hundreds to a thousand miles away.

    Just one idea...
  3. K6CLS

    K6CLS Ham Member QRZ Page

  4. W3HMK

    W3HMK Ham Member QRZ Page

    The cover of this month's QST was the final motivation I needed to decide to go! I'm looking forward to logging all of my contacts for the SEQP- but that article does nothing to describe HOW. The Nuts & Volts linked above is the first I've read describing the ecliptical effects on propagation. Great read!
  5. K6CLS

    K6CLS Ham Member QRZ Page

    Heh, yeah, same author too. The QST article could have been much more extensive.

    There are so many worthy experiments to participate in. I'm having trouble choosing just one or two. And choosing where to go to watch, and set up...
  6. N1OOQ

    N1OOQ Ham Member QRZ Page

    My guess is... nothing will happen to propagation. Keep in mind that the moon's shadow is just a large spot, something like 50 miles in diameter, and it moves very quickly, hundreds of miles per hour.
  7. KK4YWN

    KK4YWN Ham Member QRZ Page

    plus its going to rain.
  8. W0IS

    W0IS Ham Member QRZ Page

    It will affect propagation. The first somewhat scientific study of the subject was in 1925, when a radio station set up in the path of totality in Michigan and had people send reception reports. I have more written about it here:

    It stands to reason that it will have a fairly significant effect. In most parts of the country, there won't get visibly dark outside, because the human eye is so good at adjusting to changing light conditions. But everywhere, 50-100% of the sun will be covered up. So in general, I would expect lower bands to perform better than usual.

    In one recent eclipse, it was noted that the main effect on the AM band was that stations had much better range at the time they were in totality, without much difference from the conditions present at the receiving station. This was apparently because the lack of sun caused the D absorption to stop in that region, but it was a one-way phenomenon.

    I'll be set up in Hastings, NE, mostly to watch the eclipse, but I will be on the air, probably on 40 CW. I'm not going to be making any QSO's during totality, but I will try to send out a quick TEST DE W0IS during totality for the benefit of the Reverse Beacon Network, and look at it later. I expect better propagation to the west before totality, and then to the east after totality.

    If you are going to operate the SEQP, I encourage you to operate at least some CW or digital. If you do that, skimmers will pick up your signal, and you'll generate a lot more data than just making QSO's. Even if you don't normally operate CW, sending an occasional TEST DE ___ (after checking to make sure the frequency is clear) will get you picked up by the Reverse Beacon Network, and you can later take a look at where you're signal landed.

    Here's a summary of what I'll be doing:

    I've been encouraging even non-hams to take a look at the bottom of the page and see if they can do some science armed with just an AM radio. In particular, that might keep some kiddos occupied as they track the path of totality by the stations coming up out of the noise, and they can later see their work as part of a published article.
  9. KV6O

    KV6O Premium Subscriber QRZ Page

    Shut up you!

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