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Hum, perhaps you might read the relevant manual page "man setleds"

Then perhaps you might read the following web page

http://martybugs.net/electroni...

In short you are just 100% plain wrong in your assertion. You could easily use three flashing LED's to indicate all sorts of error codes.

Students can use these sensors to e.g. study the thermal characteristics of their own home or the school or perhaps a shop or restaurant and correlate them with outside temperature, sunlight, humidity, etc.. Rapid temperature changes can potentially identify inadequate insulation, and temperature fluctuations per se can point to substandard heating control.

You can also build (or buy) a compact solid-state temperature and accelerometer logger and mail those around the country to see what the ambient conditions of mail and parcels are. Once you show that this works, students (even in the range of 14-18) could conceivably land an internship with a local company to introduce a system that tracks conditions of their shipments. You can get USB-key sized temperature and humidity dataloggers for about 60$ from http://www.signatrol.com/ Too expensive for a classroom project perhaps, but potentially very interesting for commercial use.

There are electronic components (for about 2$ apiece) that act as sensors (for e.g. temperature, humidity, air pressure, light, CO2 concentrationt)(see e.g. http://martybugs.net/electronics/tempsensor/ , http://www.tempsensor.net/) .

Attach those to a low-power radio transmitter, and add a transceiver to the USB port of a netbook and you get an interesting wireless sensor network.

Basic ready-made dataloggers can be had for as little as $25 (see http://www.dataq.com/products/startkit/di194rs.htm) and you can get ready made chart display software for them plus APIs in Visual Basic, C++ etc.. They also give away one of those per month, but I consider that a publicity stunt I wouldn't want to expose kids to. An alternative is a microcontroller board can be found for $40 (see http://al-williams.com/app4kit.htm).

Building and testing the sensors from components could be a 1-semester project. Dataloggers are a more complicated proposition, and require some more electronics knowhow, but even that can be done by 15-18 year olds in one semester. Otherwise writing the data-capture software is an option too, but I'd add a full semester for that.

For giving credit I have no other suggestions than to ask for either a final report upon completion or (for additional credit) bi-weekly reports (for preference in Open Office of course, with photographs of the equipment, the measurement setup, and spreadsheet graphs showing the data) for which you provide a template.

I'm a believer in letting students submit bi-weekly progress reports in memo form (so you can see what they're doing, help them where needed, and prevent them from wasting time on dead ends and blind alleys), and then asking them to use these memos when preparing a final report. That way students learn to what progress reports are, why it's important to be able to state clearly what you've done, and how such memos can be used to spread the burden of reporting across the project. Besides which, this is how it's done in professional practice too.

As to the final report: if you provide, say, three templates with varying levels of complexity (from a 2-page leaflet to a full report with problem definition, background physics (with proper references), measurement setup, data description (data in an appendix of course), summary and conclusions, you can provide a different amount of credit for each type of report.

OpenWRT on the WRT54G(S) allows you to setup an OpenVPN server. Convenient, though the throughput isn't spectacular, due to the processing requirements demanded by SSL on the WRT CPU.

See http://martybugs.net/wireless/openwrt/openvpn.cgi and http://forum.openwrt.org/viewtopic.php?id=1800.

Ditto. Manufacturers need to know blue LEDs are not cool, they're annoying:

http://led.linear1.org/wired-magazine-blue-led-bac klash/
http://martybugs.net/articles/bling.cgi

Build a lightweight VPN server into every router

Something like this?: http://martybugs.net/wireless/openwrt/openvpn.cgi

1. Get an old POS PC from a trashpile
2. Install Smoothwall on it. It's free..
3. Install Ad Zapper following THESE directions.

Any and ALL system that you connect into your lan will have ads blocked whether they want to or not.

Yeah, here (http://martybugs.net/wireless/biquad/) is one very good site I refer to for biquad antenna construction. Another tip, when I was studying the NEETS guides that are available for free on the internet, they recommended a horizontal radiation pattern if you have to dodge through trees and urban landscape.

1. http://www/smoothwall.org

2. http://adzapper.sourceforge.net/#install

3. http://martybugs.net/smoothwall/adzap.cgi

Get them. Do it.

Try all you like, you filthy, rotten marketeers, but you won't be peddling your wares in MY house...

Hahahahahahha!!!

First, the connector on the Lucent/Avaya/Orinoco/Proxim equipment is known as "MC" or MC-Card". Cisco and others use MMCX, which is just a hair bigger and slightly differently shaped. IIRC, the Senao card uses MMCX, and you should consider it for your trip because it has higher output power and better receive sensitivity than any of the others.

Second, yeah the card's integrated antenna is crap. Anything external that's even close to the right band will do better. I disagree that external mounting is a big deal. For stumbling, an omnidirectional antenna is good because you just mount it and leave it. But for using hotspots at truck stops and such, you can manually position a higher gain antenna for best signal. The directionality will help a lot if you're at the edge of the parking lot, or if you decide to surf from the Flying J while parked at the TravelAmerica. Obviously, it's easier to aim an antenna if it's inside the vehicle with you. This also helps minimize losses from long antenna cables. I'm not worried about metallic window tint on your Vanagon interfering with the signal. :)

For antenna designs, the cylindrical waveguide cantenna can't be beat for simplicity, but it's never wise to point weird-looking tubes out the window of a vehicle, moving or otherwise. (Print out a copy of this Ask Slashdot posting, or something else to indicate that you're nonmalicious in the event that you get questioned.) I can't emphasize this enough, our society is pretty paranoid already, but the police are trained to recognize potential threats, and a scruffy dude pointing a metal tube at things is pretty high on the grab-your-gun index.

Trevor Marshall's Bi-Quad antenna design is absurdly compact, reasonably directional, and very easy to build. Marty's instructions clarify a lot of the things Trevor didn't show in detail. If you have an old double-wide jewel case around, you can build the little biquad into it for a totally nonthreatening appearance.

As for extended roadtrip suggestions: Consider a battery isolator and dual-battery setup, if it's within your budget. I was in the market for such a unit recently, and Hellroaring seems to have the best-designed product with a ton of helpful app notes and install guides.

If most of your portable gear runs from AA's like mine does, you might be pleased to know that many of the recent NiMh chargers run from a wall-wart, instead of building the entire power supply into the charger unit. Presumably, this makes the UL listing process easier by moving the mains supply out of the unit, to a transformer that can be separately listed and doesn't need to be re-qualified each time the charger gets revised. It benefits you, because the wall-wart steps down to 12 volts and the charger takes it from there. Ergo, it's dirt simple to make a car cord for such a charger, and it's more efficient than running through an inverter.

While on the subject of vehicle DC wiring, check out the Powerpole connector. It's become the standard in the amateur radio community for 12 volt supplies, because lighter sockets suck. Powerpoles are genderless, polarized, and very reliable if crimped correctly in the first place. Crimp+solder is even better.

If you're the paranoid/prepared type, ghost your laptop's basic setup onto a spare drive and keep it (wrapped in antistatic foam) elsewhere in the vehicle. You don't want to be stuck 1800 miles from home with a crashed drive in one hand, freshly reinstalled laptop in the other, trying to figure out how to download the drivers for your wireless card when said card is your only means of internet access.

Good luck, have fun, drive safe, and post some pictures from your trip!

Smoothwall has ipac-ng, so you can easily do bandwidth tracking per PC with Smoothwall.

I've been using Smoothwall 2.0 beta X for over a year now and I've had very few problems.

The most recent I'm using is Pendolino and it's great.

I have installed several customer sites with Beta5 (after extensive testing at my site) and they are all very pleased with it.

I highly recomend it. You can take an old PC and load it up and really be covered.
It's very easy to use, very reliable, very flexible.

What's even better is that you can use the built in,
transparent proxy (squid) to block ads. (sorry /., your ads too)..

I made a dull gray "this ad zapped" gif and put it in /home/httpd/zaps and edited the wrapzap file to tell adzapper to look on smoothwall ofr it's images rather than using the resources of sourceforge. I found that the black and yellow gif was more annoying than the ads it was blocking.

Man, it's great. EVERY machine that I plug into my lan automatically gets it's ads zapped. Friends and customers are freaked out and impressed with that. Then after seeing how cool it is they want a smoothwall too. Problem is I end up setting them all up for free.. ;-/

Smoothwall is very cool, get it....

WAY better solution.

Take an old PC. Install Smoothwall GPL 2.0 (router/firewall)

Then hack squid in the smoothwall and add in Adzap

I made my adzap point back to itself to retrieve the "this ad zapped" images rather than getting them from sourceforge every time, for speed, to not hammer sourceforge and to use my own custom pics. I made some very subdued pics to replace the annoying back and yellow "This ad zapped" replacements.

Anyway, since doing that, I haven't seen ad one. No flash ads, no gifs, no jpgs, no pop-ups or unders, no nasty javascripts. EVERY pc that plugs into my lan is instantly ad blocked, including total strangers that bring pc's over for repair/service. No modification is done to any other machine on the lan, smoothwall is transparently proxying port 80 and blocking ads before they ever enter my lan.

Try it, it's very, very nice... (Sorry /. your ads are blocked too...) Oh yeah, you do have a choice to use white and black lists on the smoothwall to allow SOME ads of your chosing to come through, if you so desire or to block IP's that somehow manage to sneak one through adzapper.

Some links:

KI7cx dish
Primestar dish
Bi-Quad feed for primestar DIY
10 Euro dish with biquad feed
Modifying Confier Antennas for Wireless Networking

More info: Wireless Leiden

Meant for firewall status display but could use it for anything really...