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Sunday, December 30, 2012

SolderSmoke Podcast #148


SolderSmoke Podcast #148 is available:
http://soldersmoke.com/soldersmoke148.mp3
December 30, 2012

SPONSORED BY usedradiomall.com

-- Hurricane Follow-up
-- Subliminal Mind Control to Encourage Homebrewing (beep-beep)
-- The Shortcomings of the All American Five Receiver
-- Solid-Stating a Heath SG-6 (with Farhan's circuit)
-- VK3YE's Beach DSB Rig
-- Tek 'scope connection to frequency counter
-- Mod to W7ZOI/W7PUA power meter
-- JBOTing my 20 meter DSB Rig -- A Tale of Woe
-- LU1AR "The Most Interesting Ham in the World"
-- Billy's Raspberry Pi
-- Latest QST, SPRAT, Hot Iron
-- Videos: Landfillharmonica,  Knack in Sierra Leone
-- Santa delivered a Soldering Station
-- MAILBAG

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Monday, December 24, 2012

A Christmas Present from Argentina


There is an old saying in Spanish:  "No hay mal que por bien no venga."   More or less this is the same idea as: "Every dark cloud has a silver lining."  Well, the dark cloud was my techno-agony with the parasitic oscillations (see below).  The silver lining was the e-mail from Edgardo, LU1AR, in Buenos Aires that helped me get rid of them.    Edgardo advised putting a resistor across the primaries of the JBOT amplifier stages.  This is an old "lower the Q" trick, the idea being that lowering the Q might help prevent the amp from self-oscillating.     I used 680 ohm resistors.   First I put one across the primary of Q1.  No joy. Then Q2.  No luck.  Then I put one right across the primary of that big output transformer.  That did it!  The parasitics disappeared.   And I still get a nice 4 watts of output.  Thanks Edgardo.  I hope to make a contact with this rig today. 

The real silver lining in this story comes, however, in the form of Edgardo's blog site.  Wow, what an inspiring example of Argentinian Knack.  Radios, telescopes, auto-giros.  This guy is also into homebrew DSB rigs.  Wonderful stuff.  Check it out.  (Google will translate it for you, if necessary, but even if you don't read Spanish, the pictures tell most of the story.) 
http://www.lu1ar.blogspot.com.ar/
Thanks to all who sent advice and encouragement.  Merry Christmas! 

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Sunday, December 23, 2012

Woe is me! Why Podcast is Late: Parasitic Oscillations!



I'm building my FOURTH JBOT and this one is giving me more trouble than all the others combined.  
Here are the details of my tale of woe:
20 meter rig.  Double Sideband.   The JBOT is fed by a simple two-diode, trifilar toroid singly balanced modulator.  NO DIPLEXER TO SPEAK OF.  At the output of the balanced modulator there is a 1000 uH choke to ground and a .001 uF cap to the input of the JBOT.  AF amp is an LM-386.  VXO is a very simple MPF-102 one stage ceramic resonator VXO with no buffer stage.  7 element low pass filter (three coils, four caps). 
All the transformers are wound on FT-37-43 cores.  T3 is four such cores stacked 2X2.
 
The arrangement works beautifully into a 50 ohm dummy load.  But as soon as I connect it to an antenna (a dipole out in the yard, fed with 50 ohm coax) the output signal gets ugly.  
Looking at it on the scope, instead of the nice figure eight pattern (similar to the two tone test pattern of SSB) I get ugly fuzzy outcroppings from the peaks.  Looking at the signal more closely I can see that in addition to the 14.2 Mhz signal, there is another LF oscillation at around 250 kHz. 
I've been struggling with this.  I can't get rid of the LF oscillations. The leads are all short and the inputs are far from the outputs.   I've beefed up shielding, and decoupling.  I've sacrificed a chicken to Papa Legba. Nothing seems to help.  
I THINK the feedback/oscillation is taking place in the JBOT itself -- not through the
audio amp or the balanced modulator or the VXO.
I watch the RF and the AF inputs to the balanced modulator to see if there is any difference between the stable situation (with the 50 ohm dummy load) and the unstable situation (with the antenna),  I don't see any differences. 
I even put an antenna tuner between the final and the antenna anb made sure that the antenna looks like 50 ohms non reactive.  This seems to help a bit, but the ugly instability is still there. 
Help me! 
\


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Friday, December 21, 2012

LadyAda Named Entrepreneur of 2012


Watch this video and you will see that Limor Fried has The Knack!
She and her company have brought homebrew electronics back to lower Manhattan.
Some kind listener sent me a gift certificate for Ada Fruit.  We will put it to good use, probably
with Raspberry Pi and Arduino gear.
Three cheers for Lady Ada!

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Friday, December 14, 2012

Roadkill Violins! LandfillHarmonic


Landfill Harmonic film teaser from Landfill Harmonic on Vimeo.

Wow, this is a really inspiring video about being inventive, overcoming obstacles, using what you find and putting junk to good use.  I thought you guys would like this (ESPECIALLY ROBERTO!).

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Thursday, December 13, 2012

FITSAT-1 Flashing Morse With LEDs from Orbit


Very cool:  Japanese students sent up a small satellite.  One of its capabilities is to flash Morse code messages in the visible light range using LEDs.   Prepare to peg your geek meter: 
http://www.fit.ac.jp/~tanaka/fitsat.shtml 

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Monday, December 3, 2012

PE1JXI's BITX-20 Handheld


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Saturday, November 24, 2012

Watching a Light Beam at One Trillion Frames per Second


Billy alerted me to this TED Talk presentation on an MIT Media Labs project that used new "femto photography" techniques that allow us to watch -- in VERY slow motion -- a light beam pass through a bottle. Amazing. Makes me think about Einstein's old thought experiment about running alongside a light wave (but of course here they are slowing down time...)

 Here are some details on how they did this:
 http://web.media.mit.edu/~raskar/trillionfps/ 

 Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Thursday, November 22, 2012

African Knack


Thanks to Allan, WA9IRS, for sending us this inspiring video. Just the right touch for Thanksgiving. This kid is definitely one of us. Let's try to think of ways to help him. Parts box? Radio books?

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Get SolderSmoke For Christmas! 30% off (23-27 Nov)!


Use the little mail icon (below) to forward this to those who are buying you things for Christmas!   30% off if you buy 
23-27 November.    Here are books: 




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Wednesday, November 21, 2012

NA5N, a Solar Flare, and the Very Large Array


I think I said before that Paul, NA5N, has one of those "dream jobs" for a radio amateur.  Confirmation of this came in a message he posted to QRP-L today: 

We're running a special experiment today using the VLA antennas to observe at 74 MHz (a protected radio astronomy band) and at 327 MHz.  We've hung dipoles just below the antenna subreflectors, acting as a virtual ground, and of course the 88ft dia. dishes to illuminate the dipoles.  Picks up a lot more power from the sky than I would have thought (about 30dB gain over the same dipoles in free space). 
Anyway, about 0830 MST, suddenly the system temperature climbed about 200 deg. K.  Our switched power calibration injected into the LNAs showed no shift, meaning the jump in power came from the sky, not from the electronics.  The power plot looked just like a solar flare.  Checked the NOAA site, and sure enough, we had an M4 solar flare from region 1618 ... about smack in the center of the sun.  About 1530UTC=0830MST=1030EST, Wed. Nov. 21. 
NOAA has since measured the shock wave from the CME at 1918 km/sec.  This is a fairly strong shock wave, and coming from the center of the sun means planet earth will be pretty close to the bulls eye. 
The first time in my life I witnessed a major solar flare in real time watching the "sky power" plots.  Pretty neat.  First time the astronomers involved in this experiment have witnessed a solar flare as well real time. 
Region 1618 has produced numerous C- and M-class flares past couple of days with high potentials of future activity.  This will ionize our E/F layer for elevated MUF and weak signal reflection.  Check the bands if you're not at work. 
This 1918 km/sec. shock wave headed for us will almost assuredly trigger a major geomagnetic storm in a couple of days.  If it hits Friday evening, it will trigger likely aurora over northern U.S.  It may hit Saturday.  I'll check the NOAA predictions later today and post as to the expected shock wave arrival. 
72, Paul NA5N
Socorro, NM
Currently inside of VLA antenna #5, west arm.
http://www.vla.nrao.edu/ 


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Sunday, November 18, 2012

Another VK3YE DSB Rig

Hi Bill

       A short e-mail from across the pond. Thanks for sharing the VK3YE link, so impressed I was that I have built one. 
It receives great and puts out a nice looking dsb signal, looking forward to some good qso's, ready to improve on it as we speak and looking to make a top band and 18m version also, love the site and keep up the good work...Ian
Ian Miller
G7FFV
UK


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"Road Kill" Batteries for Us?

http://news.nationalgeographic.com/news/energy/2012/11/121116-second-life-for-used-electric-car-batteries/


Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Saturday, November 17, 2012

Schematic of the VK3YE "DSB-On-The-Beach" Rig



Peter Parker's amazing 8 transistor DSB rig (featured in an equally amazing YouTube video -- see earlier blog post) has sparked a worldwide resurgence of QRP minimalism.  There is now a lot more activity on the "Minimalist QRP Transceivers"  Yahoo group (be there or be square).   Steve "Snort Rosin" Smith WB6TNL is minimalist mentoring to the max -- with his help it looks like more VK3YE transceivers will soon be on the air.  Steve was kind enough to take the info from Peter's video and turn it into a .pdf schematic (see above).  It is in the file section at the Minimalist QRP Transceivers group.  I was, of course, pleased to see the inclusion of a robust 7 element low pass filter.  

Michigan Mighty Mites are also tickling the ether.   I may pull out my single MPF-102 Yingling 80 meter rig.   You can join the Minimalist group here: http://groups.yahoo.com/group/Minimalist_QRP_Transceivers/

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Friday, November 16, 2012

Uncle Sam Wants You! (Well, really your Telescope)


 I don't think they will be that interested in my $50 Tasco 4.5 inch reflector, but I am thinking about sending in a proposal for a 1.2 million dollar series of upgrades for the old 'scope!

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Monday, November 12, 2012

A Promising Start for the SG-6 Solid State Conversion


We have kind of half a holiday today -- I have the day off, but the kids went to school.  I made use of the additional shack time to test the feasibility Farhan-izing my old, not-so-beloved Heathkit SG-6 signal generator.  I did a quick Manhattan build of the oscillator section from Farhan's sig generator (link in yesterday's post).  Using an idea from an old 73 Magazine article on a similar project (thanks Clint!), I smashed the tube (appropriate, don't you think?) and connected (using the glass stump!) Farhan's oscillator directly to the pins that lead to the switchable coils and the variable cap of the SG-6.    I just wanted to see if it would oscillate, and see if there was a big change in SG-6 dial calibration.  

Wow, it worked great!  It oscillates very nicely on all but the upper frequency band setting (20-50 MHz).   I feel confident that I'll get it to oscillate at least up to 30 MHz.   Next I'll build Farhan's buffer and amplifier stages.   The SG-6 had a switchable attenuator -- I want to include that feature in the solid state version.  I'll have to give some thought to the audio modulation feature (nice for aligning AM receivers). 


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Sunday, November 11, 2012

Solid State Conversion for a Heath SG-6 Signal Generator?



I've recently become acutely aware of the shortcomings of my signal generator. 
It is a Heathkit SG-6.  It is really old.  It has a selenium rectifier in it. It has one of those old mic connectors on it for the output.  The output is very low.  But I like the cabinet and there is a nice switchable coil/variable capacitor LC circuit in there (see above).  

In 2008 in Hyderabad, India Farhan went to McDonalds with his kids and went home with some straws.  Soon the straws are chopped up and turned into coil forms for a signal source:  http://www.phonestack.com/farhan/siggen.html

So here is my idea:  de-tube the SG-6.  Turn the selenium over to the HAZMAT authorities.  Save the coils and the cap and most of what George Dobbs would call "the socketry."  Use an MPF-102 for the oscillator, then make use of the buffer and feedback amp from Farhan's soda straw circuit. 

What do you guys think? 

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Thursday, November 8, 2012

8 Transistors = 40M DSB XCVR (on an Australian Beach)



Another brilliant rig from DSB guru Peter Parker, VK3YE.  I really liked this one.
I loved his drawing of the circuit diagram -- right there on the beach! Lots to be learned from this video.  Thanks Peter!
 
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Friday, November 2, 2012

The Hobbit Hole of QRP

In SolderSmoke 147 I mentioned that I had found some old pictures of AA1TJ's underground hamshack and workshop.  People wrote in asking me to post them.  Here they are.  I still can't find the shot of the door surrounded by snow. 









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Thursday, November 1, 2012

Lights and TV during blackouts! My Inverter ($69)

People have been asking about the DC to AC inverter that I have been using during the now frequent power outages (5 in the last two years, two of them since July 2012).  With it I can easily keep the lights on in the house and even run the TV.  Not bad for $69.  Here it is:

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Tuesday, October 30, 2012

Solder Smoke Podcast #147 -- Hurricane Sandy Edition

Hurricane Sandy backup station at N2CQR

SolderSmoke Podcast 147 is available for downloading: 
http://soldersmoke.com/soldersmoke147.mp3
October 29/30 2012
Hurricane Sandy on the way
Thanks for birthday wishes 
Einstein -- a very nice fellow with a bit of the Knack
Rocket project update
808 key chain cameras (thanks for the Amazon support!) 
Audio output transformer for Barbados Barebones RX
Mighty Midget RX -- breaking it, fixing it (with help from friends)
Freq counter connection to Tek scope  
Halli S-38E -- How to avoid electrocution?
The HQ-100's anti-drift alarm clock 
Book Review:  "Instruments of Amplification" by H.P. Friedrichs (5 Soldering Irons!) 
BANDSWEEP: 20 meter SSB via DC receiver on hurricane day
Report on outcome of the hurricane -- inverter saves the day (really the night)
MAILBAG (a big one).    

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All OK at SolderSmoke HQ

Hurricane Sandy went through here yesterday. We had a lot of water and wind.  Power went out at about 7 pm, giving me the opportunity to display my technological prowess by deploying my 1.1 kilowatt DC/AC inverter.   It worked very well -- we had lights and TV, and were the envy of the neighborhood.  We all went to sleep on the ground floor -- trees are the real hazard here.  We were very pleased to be awakened by the lights coming back on at 1:20 am.  Three cheers for Dominion Power!   I hope listeners in the storm's path had it as easy as we did.    

Podcast #147 will be a special Hurricane Sandy edition.  I should have it out in a day or so. 

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Sunday, October 28, 2012

Waiting for Hurricane Sandy


That vortex off North Carolina is Hurricane Sandy, and it is heading right for us.  It should make landfall tomorrow, perhaps in Southern New Jersey, perhaps closer to us (the location of the landfall of the eye doesn't matter much -- the wind field has a radius of 300 miles!)   It could really mess things up  --- lots of water, lots of wind, and it will collide with a cold front moving in from the west.  Yuck.   There is a good chance we will lose power.  I have pulled out my trusty Heathkit HW-8 and my solar-charged gel cell battery, so I am ready to go.  Good luck to all those in the storm's path.   

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics"
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Wednesday, October 17, 2012

Good News From Ireland!

Hi Bill,

I'm not sure what's in your sacrificial solder but it sure is good stuff!!!

I received my results today and I'm very very pleased to say I passed.

Now I can finally set my mind to building a shack...

I'm going to celebrate by ordering one of Tim Walford's excellent looking beginner kits and I've just started building Tony Park's Ensemble RXTX.

I'm not sending in my cert just yet though as I want to pass my morse test first.

Thanks again for the kind support, I'm sure it got me a good few percent on the test!!

Also thanks to Steve Smith WB6TNL and his words...

"Thousand of people have taken this examination and passed. There is no reason why I cannot also pass."

He was right!

Also I hope Dave passed, unfortunately I didn't get to meet him at the exam, hopefully we'll figure out how to contact each other, it'd be good to have a newly passed fellow ham to share ideas with.

Regards, or should that now be 73 :),

Chris


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Saturday, October 13, 2012

"Zen and the Art of Radio Telegraphy"


OM Carlo Consoli, IK0YGJ, has produced a nice book on radio telegraphy.  Very much in the spirit of the International Brotherhood of Electronic Wizards, he has made it available in Italian, English, French and German.  I have started a refresher language course in Italian and intend to use Carlo's book as reading material for the course (my instructor will be sympathetic because her son is a radio amateur).  Who knows, I may be able to improve my Italian and my CW at the same time!    

Check it out:  http://www.qsl.net/ik0ygj/enu/index.html

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Friday, October 12, 2012

The Joy of Tinkering at RIT

Our Dayton corrrespondent Bob Crane, W8SX, sent us this. Thanks Bob!

http://www.edn.com/design/test-and-measurement/4396825/The-Joys-of-Tinkering?cid=EDNToday

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Thursday, October 11, 2012

Something Different: Stop Action Movies

The stop-action film Frankenweenie is hitting the theaters here. Its mad scientist/workshop theme seems to have some Knack relevance. This morning I found this five minute film called "The Maker." I thought you guys would like it. I also liked the video (below) about some of the homebrew gear that they used to make The Maker.

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Monday, October 8, 2012

Harv's Hallicrafters HT-37: A Thing of Beauty


Good Evening Bill,

Well with sore fingers, I’m glad to report that the upper deck of my newly acquired HT-37 is complete. (see enclosed photos)
Mice had a small party in this radio but aside from the numerous corrosion spots and few frayed wires,  the task of restoring was not too over whelming.
I have had my trusty Soldering Iron in high use mode lately.
All but the final tubes have the Hallicrafters logo stamped on them.
I had to replaced the Final Tune Capacitor C55 and have gone through all the modifications done to this radio during its 52 years of service.
The previous owner added an internal Antenna Relay (grey transformer near rear of deck.) and replaced the Mic connector with a Drake style phono jack. (I guess that’s acceptable.)

Now I’m onto the re-capping of the lower deck, De-ox the tube sockets and switches. Finally, the replacement of the rectifiers with solid state devices.
I’m documenting all the details just in case there is another solder melting soul out there that wants to restore their HT-37.
With some tender care, it should last another 50 years.

Bill, Keep on learning, Keep on burning (solder that is!)

73’s & Enjoy

Harv -=WA3EIB=-


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Sunday, October 7, 2012

My Mate for the Mighty Midget


Al, W1UX, asked for a picture of the receiver that I used to listen to his dulcet tones this morning.   Here you go Al.    Here is an article on the project: 

http://www.gadgeteer.us/erart.htm


Above is the Mighty Midget RX paired up with a DX-60 and a VF-1 (circa 1998)


Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

W1UX


Now THAT'S a ham shack! My Mighty Midget receiver allowed me to listen in this morning to Al, W1UX, and friends on 75 meter SSB. One of Al's AM operating positions appears above.  Note the DX-100.  And the R-390 (want one).  And the Tek 465. I've been a big fan for years.  Check out Al's boatanchor web site:    http://www.tinyradio.com/boatanchor01.html  

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Saturday, October 6, 2012

Mighty Midget RX on a Key Chain


The key chain device will soon be carried to 1200 feet by our new rocket.



Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Friday, October 5, 2012

Sputnik Party 2012 Soapbox

Poster by Steve "Snort Rosin" Smith

3 October from AA1TJ:

Here's an admittedly late reminder that the Sputnik Party begins

tomorrow (4 October). I've been preoccupied with non-hobby concerns in
recent months but I did manage to throw something together for the
event.

My transmitter follows the lines of the 10mW, battery-powered, RF
beacon that was carried into orbit in 1958 by "Vanguard 1." You may
recall this is the one Premier Nikita Khrushchev characterized as "the
grapefruit satellite."

My present build uses essentially the same circuitry and componentry
as did an earlier, 20m version; details of which can be found at

http://aa1tj.blogspot.com/2012/06/vanguard-1-satellite-transmitter.html

The 15m version drives a 44m end-fed wire with 30milliWatts.

The receiver that I built for the event is essentially a "Q-multiplier
-> detector" type regenerative job. However, the Q-multiplication is
accomplished by a parametric amplification using a quartz-crystal
controlled pump. I thought it would be historically appropriate given
that parametric amplifiers were all the rage in the late 1950's.

I put together the keying and R/T changeover circuitry this morning.
When it appeared that "all systems were go" I began sending CQs on
21.060MHz. The band, or at least that portion of the band (the
receiver only tunes from 21.060 to 21.064MHz), seemed rather quiet,
but my 6th call netted a "dit dit dah dah dit dit." Resending my call,
I was very pleased to hear HB9DCL come back to me from just outside of
Zurich. The reports were 579/339. Frank was running 5W to a log
periodic antenna. I sure hope this is a sign of things to come!

I hope to be at the key by 1300Z tomorrow. Although my little
"grapefruit" only puts out 30mW, folks running "Sputniks" made from
ex-Soviet subminiature "rod tubes" should be at least two S-units
stronger. A number of European stations will be operating this year
and at least one station that I know of will be QRV from Japan. Just
listen for the beeps and give them a call!

Thank you,
Mike, AA1TJ

.......................


04/10/12  ( first day)
dear friends &Sputnikers
today a Belgian "sputnik clone" crossed the pond
first hit
15:22 with N0UR a 2 x sputnik "solid" QSO
Jim wrote: Thanks QSO, here is how you sounded in MN
( in attach)
16:00 second hit with AA1TJ , Mike "the inventor of all this Sputnik madness" hix 3 
this time a bit more difficult but at last we could manage to exchange reports,
between the QRM and noise at last got confirmation , 
Mike's sigs  here where 339 but still copyable
all OK with my 559 sigs then suddenly some other sputnikers came on the scene and I lost Mike
nevertheless
with my 60 years again excited as a young boy
as we made some history today hi x 3
will take a picture
for the moment a complete mess as the DC/DC invertor inside the sputnik  broke down
lost the very early contact with UA1CEG suddenly no more power in the SPUTNIK-cabine LOL
had to drag my new testbench power supply (still under construction )
or  lot of things to fix for those lausy 700 milliwatts hahahaha
73 to all
Jos
ON6WJ

.................................

News flash...Sputnik worked Vanguard across the pond. I just sent this
letter to some of the guys

Dear Friends

I won't forget this morning's QSO with ON6WJ anytime soon! As he
beeped/called CQ I could hear him riding on waves of QSB. I kept
hoping he would end on the top of the wave. It happened one time and
Jos sent "AA1TJ?" but by the time I re-sent my call we were back in
the trough of the wave. He started calling again and once again I
crossed my fingers. Finally it happened, he ended on top of a
particularly strong peak...and sure enough, he copied my callsign. It
took more effort to exchange the reports but we eventually did it! He
confirmed my 559 and I did the same for my 339 report. It must be true
that anything worthwhile doesn't come easy, because the more difficult
the QSO the more I seem to enjoy it! I copied Jos' info: "SPUTNIK PWR
700mW = ANT 3EL YAGI" perfectly on my tiny receiver. Just as amazing,
he copied my 30mW transmitter made from one PNP Germanium transistor
dating from September of 1959. Needless to say, I'm a happy camper
today. Merci Beaucoup, Jos.

Just above my operating frequency I heard PA0PJE sending "CQ Sputnik."
You had a beautiful signal here, PJ! It was easily S6 on the peaks. My
transmitter frequency trimmer adjustment is buried in a rat's nest of
wires which I didn't dare stick my hand in so early in the day.
However, if I hear you again I will definitely risk it.

Thanks Carlo/IZ4KBS and congratulations on your Russian QSO. Any
contact all with this simple stuff is reason for a celebration!

...and now back to the Hobbit Hole for another dose of QRPp.

73/72,
Mike, AA1TJ



Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Tuesday, October 2, 2012

Ham Radio Exam Day in Ireland: October 4

OK gang, it is time for us to do what we can to help a worthy Short Wave Listener transition into the world of amateur radio.  Chris will be facing the Irish radio examiners on October 4.  So please try to send some positive vibes in the direction of Ireland.  Cross your fingers (especially the ones with the soldering iron scars!)  Maybe melt some sacrificial solder. C.F. Rockey might suggest sacrificing a chicken to Papa Legba.   Say a prayer if you are so inclined.   Good luck Chris!  

Hi Bill,

Just wanted to say thanks for the great podcast and keep up the good work.

I’ve been listening for a good while now and following your subscriptions advice on things like Tim’s “Hot Iron” Constructors club and QRP/Sprat magazine.

I’ve got my Amateur Radio licence test in 2 days time (4th Oct) over here in Ireland (Dublin’s Comreg Offices) so please give all the candidates a mention and wish us luck.

Great book as well…  When I’ve had my fill of studying I switch over to your book for a while to relax a bit and read your thoughts on getting to grips with it all.

There’s only one licence here in Ireland so it’s Full or nothing  so it’s going to be tough! My brain is well and truly fried!!

I’m determined not to be a (can’t even remember what you call them in your book ha ha) “User” and go out and buy everything I need so I’m looking forward to lots of construction projects when (IF!) I get my licence J

Best Regards (I don’t think I’ve earned my right to use 73’s yet),

Chris
(EI1628 SWL/qrz.com)


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How to Get Ready to Build a BITX-20




Continuing with our workshop inspiration theme, I spotted this in the BITX-20 mailing list this morning.  The response is from Farhan: 

blake,

i would suggest a different route. a long and winding one, that will
finally lead to a bitx.

the idea is to learn. you do this by understanding what you build and
building what you understand. by 'understand', i specifically mean, being
able to measure. here is what i suggest, buy yourself a bunch of 2N3904s
from the local radio shack and some resistors and caps. then build this :

http://www.phonestack.com/farhan/testosc.gif

this is an oscillator. if you plug a coil between the open ends, it will
become a vfo, if u plug a crystal, it becomes a crystal oscillator. you can
use your frequency oscillator to check the frequency it is oscillating at,
etc.

with this, you would have mastered the first of the three blocks that make
up almost every radio circuit. but next, you must make another test
instrument. a power meter. most of us ham start out with a simple RF probe.
while that was fine and dandy for its day, now we can do much much better.
we can make a very accurate power meter that enable you to measure things
as finely as anybody in this business. W7ZOI has designed a super simple
power meter. it is available as a kit.
read about the power meter here :
http://www.kangaus.com/Documentation%20files/Power%20Meter%20Documentation%20May%202011.pdf
you can purchase the kit at www.kangaus.com
(I have no business interest with kanga or any other kit manufacturer)

with the power meter in place, you can now measure the power levels coming
out of any circuit with great accuracy.

now, you can build a single stage feedback amplifer (there are six of them
used in the bitx) on a copper clad board. using the test oscillator as an
input, you can measure how much gain the amplifer has (measure the
oscillator output, then connect the oscillator to the amp and ,measure the
amp output. the, amp output - oscillator output = amp gain).

of course, while building both these blocks, you will discover what
voltages to expect at which junction of components in both these blocks.

next, you can build a step attenuator. which is a really simple thing and
of immense value in the home lab. here is a design
http://www.arrl.org/files/file/Technology/tis/info/pdf/9506033.pdf
or you can now buy it in a kit form from
http://www.qrpkits.com/attenuator.html

finally, you can build a simple signal generator like this :
http://www.phonestack.com/farhan/siggen.html  . this will allow you change
frequencies and measure what a circuit does at different frequencies. you
can use this to test how the filters are doing and get them to 'spot' where
you want them to.

so, there it is, a signal generator, a power meter, step attenuator, test
oscillator. four, very simple test instruments that you  can build
yourself. they will give you one helluva education in radio. and within
weeks, you will understand and start building on your own!!

- farhan


> Quoting bfabman :
>
> Hello Everyone, I have been watching the group for a few months now
> with interest. I have no electronic experience to speak of, but I have
> a burning desire to make one of these, and I am wondering what all of
> you think of someone like myself building one as my first real radio
> project, to be used for qrp mountain topping. I don't have any
> electronic test equipment for the final alignment, other than a
> standard DIG vom meter. (I am willing to buy some equipment if
> necessary) I think that this would be an awesome winter project just
> don't know if it would be over my head. If I got it all built, could I
> actually get it aligned and working properly. I did make a Norcal
> frequency counter project last year and it turned out very well. Thanks
> for your opinions before I spend the money. Blake
>
> Paul Daulton K5WMS
> beacon WMS 185.302 khz qrss30/slow 24/7
> Jacksonville,Ar 72076
> em34wu

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