Monday, 24 October 2016

Observing my own 30m WSPR TX results last week(s)

I dare to have my WSPR W5OLF 1W transmitter almost on 24/7 with 18 minute TX intervals (still continues). It might be a interesting thing to analyse who received me and when. But I haven't got the time for it. Hoping for some new ones in my WSPR log, so far only one (9A2WB Croatia). Still nothing from south and central America, could it be they are not allowed on 30m digital? However some interesting reports in the morning did catch my eye. Those are the reports from the USA around 8-9 UTC. Most of the time just one spot, sometimes a couple of spots. It seems it is a different from normal path but excisting almost every day according to my log. PH0NO Lars did point me at some propagation predictor called Droidprop which is a app that installs on my android phone. I actually already installed the app but never used it before. Anyway, I predicted 30m on a particulair day I saw K4COD spotted me (just as a example so I have a locator).

Normally 30m opens late in the evening. But you see that one spot again on 8:10 UTC. Now what does the prediction say. I thought to use both Droidprop as VOACAP although they say the same. See that peak at 8 UTC? But it just is below 10MHz although there is a small possebility it could rise a bit. I discussed it with several operators because I think it is much more likely that it these spots are made on longpath.

Look at the prediction. The MUF goes beyond 10MHz, actually there is much more chance for a long path signal to travel to the USA over the day. But I haven't got a directional antenna on 30m and can't prove it. I'm not a expert either. Interesting to think about it just as a experiment.

The 1W WSPR TX is normally powered from my solarpowered battery in the garage but since it is in my shack now I connected it to a new homemade device. It's a mini switched power supply with over/under voltage protection. It gives a 4 Amps max with 13V output. Especially made to power my FT-817 at vacation as a conventional power supply was too heavy and too big. I'm testing the durability before I will take it with me. The small TX does a great job on it at least. I still want to change some minor things on it. So a review of the internals and test will be given later on on this blog.
30m WSPR TX @ PE4BAS

9 comments:

  1. Hi Bas, for a good prediction i would take CW for the mode, not SSB. Though you use SSB for sending WSPR the characteristics are more like CW, even smaller. Will not make the MUF higher but your prediction for minimum power will be better.

    73 de PE2KM

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    1. Hello Kees, I don't think it will make much difference with 1W only. The MUF stays the same. Percentage of reliability will be higher but not that much. 73, Bas

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    2. Hi Bas, according to a blogpost from Bert Pa1B (with your name in it ;-) ) it is a difference between 1/400th (WSPR vs SSB) or 1/20th (WSPR vs CW). That is a huge difference when you want to know how propagation might be. The 1 Watt SSB could be giving zero propagation while CW prediction might be giving "some possibility". I would not be surprised to find out one week of bad orediction with several contacts in WSPR due to this difference due to prediction in SSB. ;-) http://pa1b-qrp.blogspot.nl/2013/03/ssb-vs-wspr.html

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  2. Hallo Bas, leuk dingetje die W5OLF wspr transmitter. Mooi voor 24/7 wspr. Die App is ook wel handig. Ik heb ooit Costa Rica op 30 meter met wspr binnengehaald. 73 Paul PC4T

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    1. Hallo Paul, ja leuke apps voor de smartphone. Ooit ook Costa Rica gelukt op 30m, volgens mij was dat Casey. 73, Bas

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  3. Hi Bas - your posting made me get out my old W5OLF transmitter too! I hit the button a moment ago and received 3 spots from VK. 30m really is an amazing band. How are you establishing 18 minute intervals - gym boss?

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    1. Hello John, yes I programmed the Gymboss for 18 minutes. If I ever get the chance to modify it with a cheap GPS timer that would be great. Now I have to get to the TX every 29 hours to start it again. I tried longer intervals but noticed timing gets to far off then at the end. 73, Bas

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  4. I am also now interested in the W5OLF again!

    The daytime would not ordinarily be expected to yield a long, chordal hop path to the USA, as it needs receding night time and advancing daytime hemispheres.

    Rather than looking at circuit reliability, it's often more close to reality to check the Area propagation page: http://139.162.54.202/proppy/area

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    1. Wow, thanks for the link. I have seen this page before but then it was not as interesting as it is now. It is certainly interesting especially when using a directional antenna. 73, Bas

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Thanks for your comment. Bedankt voor je reactie. 73, Bas