Save 20% On SolderSmoke and Other Books

Through tomorrow -- save 20% Coupon Code: SPLISH
http://soldersmoke.com/book.htm

CFL Light Bulb Schematics

Lots of good parts in those new fancy bulbs! This site provides schematics for the major brands. Very useful. Try not to eat the mercury in the tubes.
http://www.pavouk.org/hw/lamp/en_index.html#bigluz20w

Drect Conversion Receivers in New South Wales

Dear Bill,

You might vaguely remember I sent you some audio for Soldersmoke a year or two back that was recorded at the New South Wales home brew group here in Australia.

The home brew group is wonderful: it's not a club. you can't join. no-one is in charge. Every so often we have a "challenge" (which is not a competition - no-one wins).

Anyhow, recently the "challenge" was to home brew a direct conversion receiver that could be used to listen to the sunday morning broadcast here on 80m 3959KHz.

On Sunday we got together to present what we'd come up with. Alan, VK2ZAY, does great work but couldn't come so he sent in a video of his creation.

I videoed the proceedings, badly edited it, and stuck it up here:

http://www.youtube.com/watch?v=rF1WoPDajsU

This challenge was good because it was achievable by dunces like me and because the objective was the same for everyone - listening to a certain broadcast. I hope the video might encourage new home brewers.

Keep up the great work, I watch your blog and always enjoy a new podcast.

best 73's

Peter, VK2TPM

My Other Car was Homebrewed with Junkbox Parts!

At the SolderSmoke Store we have a bumper sticker to that effect.

Here's a guy who actually did it!
http://jalopnik.com/#!5785679/homeless-man-builds-his-own-car-out-of-junk

BTW: There is FREE SHIPPING from the SolderSmoke store through today: Be sure to order $30 or more through Sunday and use code: 2DAYFREE

SolderJob! Professional Knack and Hack Opportunity!

Oh man, this one is tempting. Almost makes me want to give up up the diplomat gig and move out to San Mateo... Check this out guys. This looks like a great opportunity for one of us. From the always awesome Hack A Day site:

Hackaday.com is looking for an experienced hacker/writer to join our team doing original hacking and modding projects on video. Are you energetic, outgoing, and passionate about hacking/modding? Can you solder AND explain what you’re doing and why? Come join our team and modify/hack/create things daily with a professional film crew to be aired on HackADay, then post a writeup detailing how you did your hack. Let your mind run wild, combine Mythbusters with Ben Heck, can you do it?

http://hackaday.com/2011/03/24/hackaday-is-looking-for-a-full-time-project-builder-video-host/

Back to the Future: Packets from the Space Station

Readers will have noticed that I have an affinity for beacons. All kinds of beacons: WSPR, QRSS, 10 meter CW... (Tony Fishpool says I have broadcaster tendencies.)

My favorite was a VHF Digital Satellite beacon. Out in the Azores, I had my old Kantronics KPC-3 Terminal Node Controller hooked up to a 286 computer and a Realistic HTX-202 HandiTalkie. Antenna was a ground-plane made from a coat-hanger. My rig would burp out packets all day long, and occasionally either PC SAT or the International Space Station would fly over and relay my signal to stations on the European continent or, sometimes, on the east coast of North America. I had APRS data in my packet, including a nice little island with a palm tree icon which would show up on the on-line APRS maps.

Well, after watching the Space Station (and the Shuttle discovery) fly over a few weeks ago, I got the urge to get back into the outer space packet game. Last weekend I dug out the old HT and KPC-3. I even found the cables. For the computer I put to work the OLD Toshiba Satellite Pro (appropriate, eh?) that Kevin, ZL3KE, had helped me revive.

Yesterday before going to work I noticed that there would be a nice pass of the Space Station at around 0750 local. I took a little mag mount antenna and left it on the ground in the backyard. I tuned the HT to 145.825 MHz and fired up the Windows 3.1 terminal program on the Toshiba.

When I returned 10 hours later... SUCCESS! Lots of space packets on the screen: KB1GVR, W1TMS, W1CGT, W1GSH, VE2TMW...

So far I'm only receiving, but soon I hope to be sending
PACKETS TO SPAAAAAACE!

SolderSmoke baby-wear!

A podcast listener sent in this picture of his beautiful baby daughter with a piece of clothing from the SolderSmoke Store that seems to be a bit QRO!

80 milliwatts to New Zealand (and Italy)

I realize that having your QRSS signal show up on a distant grabber is no big deal, but this was the first time I've seen the signal from my little DaVinci Code rig make the trip to ZL. You can see my shark fins in the screen shot above. It was just before dawn here, so gray line must have been helping. A Solar Flux Index of 92 also helped. My shark also made it across the Atlantic (and half the Med!) Mauro IK1WVQ's grabber made this nice capture (looks like this was around dawn at his location):

I measured the voltage at the antenna terminal this morning. Less than 2 volts peak. Assuming a 50 ohm load, that's about 80 milliwatts. This is all especially gratifying because yesterday I was out in the backyard with a slingshot and a fishing reel, putting a bit more wire into the trees. It worked!

Here's the transmitter and the schematic. FSK is from a simple two transistor multi-vibrator (G0UPL's circuit -- you can see it in the lower left):

From the good folks at Sierra Radio (our sponsor):

Want to learn to design and program with microcontrollers?

Want to add “smarts” to your next ham radio project?

Whether you are new to microcontrollers or an experienced designer / programmer, the HamStack is a great platform for your next project. Based on the Microchip PIC architecture, the HamStack can be programmed in C or Basic.

Many people ask us how to choose the best hardware and software tools for developing ham radio projects with microcontrollers.
Up to now, there really has not been a great answer to that question.

So, in traditional ham radio fashion, we put a system together. We call it a HamStack.

The HamStack platform combines popular PIC microcontrollers, a set of circuit boards, great C and Basic language compilers, in-circuit programmers and a set of easy to follow instructions and design examples that are useful for the ham radio operator.

For more info:

http://www.hamstack.com/hamstack.html

Another Mighty Mite Success Story!

Bill:

I started listening to Solder Smoke this winter, and I'm now up to episode 81. Since I'm new to homebrewing, I wanted to say that I enjoy the discussion of good projects to start on for homebrewing equipment, particularly the discussion of the Michigan Mighty Mite, which I understand was your first HB TX project. After hearing you mention the transmitter on the show, I looked it up on the Internet and found the schematic. A few hours later and I was on the air. My first contact with it was with KB1TSG, Jim in Randolph VT, receiving a signal report of 449. From my QTH in Monroe, ME that's a distance of 186.5 mi ( 300 km) as the crow flies.
I've learned a lot listening to Solder Smoke over the past two months and listen to it while in the car, at work, and while walking my dog on the back roads of Maine. Thanks for such a great educational and entertaining show.

73,
Neil

--
Neil Caudill
KB1UAL

Free Shipping on SolderSmoke -- The Book

Use Coupon Code Ground 305 and get free shipping on "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm

Don't just buy "SolderSmoke -- Global Adventures in Wireless Electronics"
but check out these other fine Knack-related publications:

http://stores.lulu.com/6sj7comics ("Lid, Kid, Space Cadet" "Sky Buddies" by Jeff K1NSS

http://stores.lulu.com/ian_g3roo (Ian, G3ROO's amazing antenna book)

http://www.lulu.com/copperwood ("Carl and Jerry" books -- scroll down a bit)

http://stores.lulu.com/soldersmoke (SolderSmoke and Bill's other book)

WSPR Direct Conversion Receiver: On the Air and Online

In a testament to the sensitivity of the WSPR system (and I mean that in the technical, not the emotional sense) I got a couple of reports indicating that my very QRPp WSPR signal was, well, a bit obnoxious. I think part of this results from the fact that I'm one of the few people using a double sideband transmitter -- the lack of filters makes my signal look a bit different. But I do have an AC hum problem that shows up on receive screens. And because I haven't worked out the circuitry to allow the WSPR software to move my little transceiver from transmit to receive, I'd been leaving it in 100% transmit mode. I can understand why people didn't really like that.

So, on the theory that it is better to give (reports) than receive, and in keeping with the old idea that all ham radio stations should from time to time RELEASE the push to talk switch and LISTEN, I have magnanimously taken my homebrew DC/DSB WSPR system into receive mode. I'm in 0% transmit. I'm listening all the time, and automatically uploading reports on the stations I hear. Pictured above is the map from WSPR system page showing my spots from last night. Below you can see what my own WSPR system display shows. (I need to adjust my W3PM oscillator a bit. I may be a few hertz off and I am probably missing a bit of the 200 hertz wide WSPR band).

I was pleased to see W3PM's call on my map. An article by Gene provided the inspiration (and much of the circuitry) for my WSPR rig.

My receiver is very simple: The RF from the antenna goes through a low-pass filter directly to an SBL-1 mixer (thanks to Jim -- AL7RV). There it mixes with LO energy from the W3PM Colpitts oscillator. From there it goes to the KA7EXM discrete component AF amp.

You can watch -- almost live -- the stations I am receiving by going to
http://wsprnet.org/drupal/wsprnet/map
just type N2CQR in the box that asks for the call.