Saw this news item describing an interesting project using VLF to monitor the ionosphere, schools can sign up to get free hardware and participate.
AAVSO (American Association of Variable Star Observers) has a Sudden Ionospheric Disturbance (SID) project.
http://www.aavso.org/observing/programs/solar/sid.shtml
Here is their hardware page, including details of constructing your own SID receiver,
which is considerably simpler than the ones referenced in the article.
http://www.aavso.org/observing/programs/solar/equipment.shtml
Steve
Do you have a link for the design referenced in the article?
Go to the link referenced in the article:
http://solar-center.stanford.edu/SID/
Click on “Quick Overview of SID Monitor”
Under “Technical Descriptions” is the link to the User’s Manual
Toward the bottom of the page is a table with links to Schematics and Photos
There do not appear to be schematics available on the AWESOME Monitor page,
although there are a lot of interesting user’s documents.
Steve
Cool. Interesting idea using a digital filter to tune the RX. I see the manual has a link to the AAVSO design, but implies it needs a lot more tinkering “Although the electronic circuit is easy to assembly, it requires a good deal of expertise to debug and tune.”
The design they refer to is basically a big honking multi-turn wire loop antenna, directly tuned by a capacitor, hooked directly to a detector-amplifyer. bleah.
However, the AAVSO also has schematics and circuitboard layout for a two IC / four op-amp receiver that uses a gyrator to create a virtual inductor for tuning, using a pot. It is probably not as selective or sensitive as the Stanford model, but is in general use in the AAVSO SID monitoring group, so it is adequately servicable.
http://www.aavso.org/observing/programs/solar/gyrator.shtml
Here is a link to a further development of the gyrator receiver, the GyratorIII. Circuit boards for it are available from Far Circuits for $7.50 (+postage)
http://www.astrosid.it/
Here’s a huge page of links, focused on detecting Gamma Ray Bursts via SID:
http://www.infiltec.com/SID-GRB@home/
The receiver section is about half way down the page.
Seems like nobody’s thought of using 1-wire devices for PC interfacing. 
Steve
I think the key to the stanford one is that they wanted to send out pretuned units. Probably is more sensitive though, IIRC (and it’s been a long time) it’s hard to get any decent Q out of a gyrator.
There are sound card apps that will do the whole thing in software too.
Thanks for that links page, it’ll keep me busy for a while 
Isn’t it the wrong time in the solar cycle to be encouraging kids to be searching for SIDs? It might be a couple of years before they see one!