Homebrew QRP Contest... With DSB!

Walford Electronics Brendon 80m DSB kit

Hi Bill

I trust all is well and that the roadkill PCs are not fighting back. Thought you might like to hear about a new contest we are trying here in the UK. Having assisted lots of new knack victims to build their first rigs at the 3 Bath Buildathons we thought we should encourage them to get on the air - 30 QRP DSB rigs on 80m all at once - now that's what I call a contest.

We have opened it up to any QRP voice radio to cover the QRP appliance operators but homebrewers get extra points. Not sure how much support we are going to get but there is a £50 voucher for Walford Electronics kits up for grabs.

Hopefully this will be a fun contest with freindly extended exhanges rather than the all too common '599 1002 73 QRZ'. Picture is the Walford Electronics Brendon 80m DSB kit in all its glory.

73, Steve, G0FUW

Big Filament -- On the Sun

The WSPR system has become something of a personal solar activity detector for me. I know, there are lots of ways to detect solar activity: there's the internet, of course. WWV is also there. You could even set up a small telescope and (with the appropriate eye-saving screen or projection systems) watch for spots yourself. But I like using my 20 mW DSB WSPR signal. If I get up in the morning and see that my little signal has been received during the night in Norway by LA3JJ (1950 km) I know that something different is going on with Old Sol.

LA3JJ was detecting my signals all night long last night. And other stations in Europe were picking up U.S. and Israeli stations throughout the night. So, what was happening on the sun? It may have had something to do with the filament pictured above. For more info on this kind of solar event, take a look here:
http://www.ips.gov.au/Educational/2/4/1

QRP Quarterly -- Winter 2010

Lots of great stuff in the latest edition of QQ from QRP ARCI:

Mike Czuhajewski's "Idea Exchange" column has been sending out great ideas for many years now. In this edition he opens with a piece from Wes, W7ZOI, that originally appeared on the EMRFD mailing list. It deals with diode ring mixers, specifically the power requirements for the local oscillator. What do they really mean when they specify 7 dBm? Wes explains: "If we say that the LO power is +7 dBm, what this really means is that a signal generator is attached to a power meter or spectrum analyzer and adjusted to deliver +7 dBm at the desired frequency to the 50 ohm instrument. Once the power is set, the cable is disconnected and reattached to the mixer." I'd always wondered about how to measure that. Thanks Mike! Thanks Wes!

Preston Douglas, WJ2V, has a nice article on our latest craze: WSPR. Preston also discusses SDR radios -- his encouraging comments may help me get out of my current luddite curmudgeon rut. Preston mentions recent efforts to use a BITX-20 for WSPR and concludes that this would be "a tall order for any analog rig." This comment lessened my feelings of inadequacy about my SDR SMT problems, because I recently used my ancient Drake 2-B to receive WSPR sigs (see earlier blog entry). Luddites Rule! But Preston is right -- it's not easy! But -- at least for a little while, before drift takes you out of the band -- it can be done.

Ward Harriman, AE6TY, writes of a "homebrew" SDR project. In his opening paragraph, he tells us what the term "homebrew" means to him: "homebrew design, homebrew assembly, homebrew programming, homebrew in a wide range of disciplines both familiar and untried." That's pretty hardcore! FB Ward!

Jim Osburn, WD9EYB, has a nice article on "circuit stickers" and how they can be used to simplify project construction using a variety of circuit boards and breadboards. I really liked Jim's description of old Electronics Illustrated projects in which they pasted a diagram to a wood base and then put finishing nails at specified points. Components were then soldered to the finishing nails. When the thing works, you can say you "really nailed it!" (Sorry!) Cool technique.

Thanks to the folks at QRP ARCI for another inspiring edition of their wonderful magazine. If you are not a member, you are missing a lot. Sign up for the club and the magazine here:
http://www.qrparci.org/

Solar Rocket Destroys a Sun-dog

Continuing with our solar theme, here is a neat little video taken on Feb 18 by a thirteen year-old kid. It shows the Atlas rocket carrying NASA's new Solar Dynamic Observatory crashing through a "sun-dog" and obliterating it with the rocket's shock wave. Obviously an auspicious beginning for this mission.

Sunspot 1046 Explains Mysterious Rome-Norway Propagation

I've been trying to understand the propagation conditions that caused my little 20 mW DSB signal to be received ALL-NIGHT-LONG at a distance of 1900 km by station LA3JJ on the night of 12/13 Feb 2010 (click here for more details).

A visit to spaceweather.com provided the answer. At around 1126 UTC on 12 Feb we had the brightest solar flare in more than two years: Sunspot 1046 produced an M8.3 Flare. Helge Mortensen in Norway reported that on 15 Feb in Norway there was "a fantastic blast of aurora." He took a beautiful picture of it (above). Could it be that we see in this picture particles from the same flare, or a coronal mass ejection associated with it?

One of the really cool things about the spaceweather.com site is that it includes lots of input from amateur astronomers and photographers like Helge. Emiel Veldhuis in the Netherlands happened to be observing 1046 when the M flare occurred and he took this series of shots:

Terje Isberg in Switzerland was listening to a DRM station on sortwave. He observed and recorded the radio blackout (SID) caused by the flare:
Rogiero Marconi in Brazil took this shot of the sunspot:
Amazing stuff. This is a good example of how WSPR really puts you in touch with solar conditions and space weather.