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Sunday, January 18, 2009

SolderSmoke 99

SolderSmoke99.mp3

January 18, 2009
Epiphany in Rome -- La Befana brings two Gerbils (Dot and Dash)
Ice skating near (but not on!)the Tiber
QRSS: Eldon's beacon spotted. 723 miles with 15 millwatts
QRSS Calibration Problem: My proposed solution
A Tale of Two BENELUX Grabbers: ON5EX and PA1SDB
Watching VK2ZAY cross Tasman Sea. Watching G6AVK reach VK6DI
Inspiration from old SPRATs: From PA3BHK and W7ZOI
Book Review: "Empire of the Air" (Good bios, but author Knack-less)
AA1TJ's CFL revolution reaches Cuba. Now a CFL receiver.
AA1TJ's "Reggie" converts all sigs to QRP!
Several new videos on the Blog (from WA7MLH, N0TU, KD1JV)
MAILBAG: Ragav VU3VWR has Knack since 9th grade. Wants to QRSS in VU
Nick M0NJP likes show, getting used to the voice, Amazon UK instructions
Bryan VK3HXR has eeePC running Ubuntu
Paolo IK1ZYW has external keypad chips for FT-817 (available at cost)
Jim AL7RV's wife thought SolderSmoke gave him a fit. Agrees on 1)design 2)build
Wes W7ZOI on feedback circuits
Joe Rocci has an LtSpice model for the NE602
Gerri EI8DRB asks if he should buy a Drake 2-B (Uh... YES!)
Steve "Snort Rosin" Smith : SMT paste lacks bouquet of 60/40 multi-core
Chris KC2LFI prescribes 3500 Hz notch for sibilant SS problem (advice followed)

Saturday, January 17, 2009

Homebrew Rigs from WA7MLH



Jeff Damm, WA7MLH, was the builder of some of the rigs that appear in "Solid State Design for the Radio Amateur" His DSB/CW Direct Conversion receiver for 75 meters is in that book. Last January, Jeff put together a video that describes some of the rigs and pieces of test gear currently in his shack. Beautiful stuff.

Thursday, January 15, 2009

International Year of Astronomy -- 2009


Hey, the signals are electromagnetic. They are very QRP. And the receivers (well, at least the "amplifiers") are often homebrew. It's 400 years since Galileo spotted Jupiter's moons. To commemorate this, we have IYA2009. The organizers are developing a program to allow people to build their own simple telescopes, and are encouraging those who already have 'scopes to get out and let their neighbors take a look at the wonders of the universe. We did a bit of this "sidewalk astronomy" in London. We'll do our part for IYA2009 by taking our 6 inch Dobsonian out into the piazza here in Trastevere. Check out the project web site:
http://www.astronomy2009.org/globalprojects/cornerstones/galileoscope/

RADIO PIONEER: HAROLD BEVERAGE

I came across this interview with Harold Beverage, inventor of (among many other things) of the antenna that bears his name. I liked his description of the personalities and design methods of some the people he worked with (including Ernst Alexanderson).
Take a look: Beverage IEEE interview

Wednesday, January 14, 2009

Eldon's Beacon: GRABBED!

Last week we put out an all points bulletin for the new QRSS beacon of OM Eldon (scroll down a bit). Yesterday the signal was captured by Stu. Distance covered: 723 miles. Eldon's power out: 15 milliwatts. That's correct: fifteen milliwatts (Eldon had earlier calculated 150 milliwatts, but this turned out to be incorrect). Above is Stu's screen shot -- you can see Eldon's FSK signal: WAOUWH (read along the top of the square wave) at around 10140050 Hz.

Here is their e-mail exchange:

Re: Is this your QRSS beacon?
Tuesday, January 13, 2009 6:17 PM
From:
"Eldon"
To:
"Stu"
Thanks Stu, and thanks to Bill Meara and SolderSmoke.com
This is my my FIRST confirmed QRSS report from my first QRP rig, it is about 150mw into a North South 6 foot Loop about 6 feet AGL.
You represent it on about the freq that I think it is - without too much calibration on my part.
See: http://qth.map.googlepages.com/?qth=CN97BV43TU&from=CM87vk
Is your Grabber online?
Thanks for the report.
Regards, Eldon Brown - WA0UWH
Don't let the Zero land call fool you, I got it many year ago while in the Navy stationed at Denver, now located in Seven land near Seattle.
eldonb@ebcon.com

On Tue, Jan 13, 2009 at 12:39 PM, Stu wrote:
Eldon,
Copied the following screen shot on 30m today a few minutes ago – I think the FSK is your callsign – WA0UWH?
Copied with Spectrum Lab in CM87vk – TS-B2000 with 160m inverted L plus antenna tuner to load up on 30m
73's
Stu

Monday, January 12, 2009

KD1JV's Surface Mount Video

OK SolderSmoke fans, here's a video for YOU! Steve "Melt Solder" Weber has put out his first video. It is about surface mount soldering. It is all very interesting, and some actual solder smoke is released, but I was a bit disturbed when Steve put the PC board on an electric stove and then started using this purple thing that looked and sounded like a hair dryer. Made me yearn for my Weller soldering gun. Great video Steve, thanks!

Saturday, January 10, 2009

The QRSS Calibration Problem: A Proposal

Eldon's effort to be seen by the 30 meter online grabbers (see below) reminded me of the big problem I faced when I first built my QRSS beacon: getting my signal into the very narrow (100 Hz wide) QRSS frequency band. If you think crystal control will solve this problem, think again: Almost all of us are using crystal-controlled transmitters, but circuit and component variations can easily put your signal far outside the freq range that the grabbers are watching.

I was able to get into the band because I was able to find a conventional CW beacon fairly close in frequency to the QRSS band. I used IK3NWX on 10.141800 MHz. Knowing the frequency of this beacon (it was avalable on the web), I used the ARGO and Spectran soundcard programs to put my sigs where I wanted them to be. IK3NWX was useful because it was so close (within 2 Khz) to the QRSS band -- I was able to put both the NWX signal, and my target freq on the screen. Later, I built my "DaVinci Code" reference oscillator -- it serves as a freq reference that I can use (again, with Spectran) to get back in the band after working on my transmitter (for those times in which I can't hear IK3NWX).

It seems like a lot of guys in the US and Canada are now getting into QRSS. Many may face the same frequency calibration problem. Are the frequency readouts of the ubiquitous Kenwood/Icom/Yaesu rigs accurate enough to help? Do they go down to the tens of hertz range? I suspect they do not.

What new QRSS ops in the U.S. and Canada might need is the North American equivalent of IK3NWX's beacon. It should probably be fairly high powered (but 5 watts would probably do the trick). Conventional CW would be better than QRSS (it needs to be heard). The frequency should be outside but within 1-2 kHz of the upper or lower QRSS band edge. A station out in the Great Plains would probably be able to serve the large ham populations of both coasts. Perhaps we could arrange for the calibration beacon to be on at certain times (daytime on the weekends?). Of course, the key would be to employ a station with very accurate frequency measurement ability (down to 1 Hz) and a highly stable signal.

What do you guys think?
Designer: Douglas Bowman | Dimodifikasi oleh Abdul Munir Original Posting Rounders 3 Column