Psst... I know a guy with some caps.... Variable caps... Real beauties.... But only for Mighty Mites.

Feast your eyes my friends.   That is 400 micro-microfarads of variable capacitance.  (400 picofarads for you sophisticated young folks.)   A benefactor interested in expanding the ranks of the Color-Burst Liberation Army has stepped forward to make us an offer that is hard to resist:  He will send ELIGIBLE recipients one each of these fine electronic components for the cost of postage (approximately 6 bucks in the USA). 

He has specified that ELIGIBILITY is limited to those who need this part to build or complete a Michigan Mighty Mite.   And I have been appointed "Grand Poobah and Chief Arbiter of Capacitor Eligibility." 

So here is the deal:  Send me an e-mail telling me about your planned or stalled Michigan Mighty Mite project.  Include some information about your personal "Knack Story"  -- tell us why you share in this strange compulsion to build a largely useless 250 mW 3.579 MHz oscillator.   If I find your plans believable and your Knack Story compelling,  I will recommend you for a capacitor.  Purely aspirational MMM projects and obviously fabricated Knack Stories will not make the cut.

Supplies are limited, so act now! 

Stuart AC9LZ's Mighty Mite

FB Stuart!  Great work.  Pete is sending you info on a Low Pass filter that will clean up that harmonic-rich signal. 

Words of Wisdom for Homebrewers -- From Dave Metz, WA0AUQ

When you are done, be proud of what you have accomplished! Use it on the air and show it off to your friends an amaze them. Then clean the bench and start dreaming about your next project. 

David Metz, WA0AUQ

http://www.fpqrp.org/homebrew.html

Summary:

• Decide if its important to do
• Study the prior work of others
• Make a preliminary simple design, document everything you do!
• Round up your parts
• Build in modules! Make one module at a time work.
• Don't get discourage, ask questions, finish what you start

http://www.fpqrp.org/homebrew.html

There is a lot of tribal knowledge and homebrew wisdom in this link.  I tried to find a picture of OM Dave, but he has kept a low profile on the www.  The best I could come up with is a symbol of the club that he has been associated with.  Thanks Dave!

Here is the full document:
http://www.fpqrp.org/homebrew.html

Brazilian Minimalism: The Curruira Transmitter

Miguel PY2OHH is the Wizard of Sao Paulo. This morning I was looking at his wonderful web site and came across this little rig.  It seems a bit simpler than our beloved Michigan Mighty Mite.  And the folks down in Brazil had several of these on the air and made contacts with them.  FB.  Miguel hints they may turn this rig into a transceiver. 

Here is the Curruira:

http://py2ohh.w2c.com.br/trx/curruira/curruira.htm

 

 

The rig is named for this little bird: 

 

 

Gregory Charvat HAS THE KNACK

Gregory Charvat N8ZRY

Yesterday I was talking to Allen W5SQK on 17.  He mentioned that he been working in his shop. You don't hear that too often these days, so naturally I asked what he was working on.  Turns out that OM Allen is building a coffee can radar!   He is enrolled in the MIT Lincoln Lab's Open Courseware Project (which looks very cool).  We had a great QSO, sharing tales of woe about the release of magic smoke from (dis)integrated circuits.  These are the things that pull us together my friends!

 

On the MIT page the name of a faculty member caught my eye: Dr. Gregory Charvat N8ZRY. Greg's rigs have been discussed on this blog at least twice, but it wasn't until today that I became aware of his many other interesting technical activities.  

 

Videos: 

https://www.youtube.com/user/charvatg

 

Bio:
http://glcharvat.com/Dr._Gregory_L._Charvat_Projects/About.html

 

Greg's KNACK STORY:

http://glcharvat.com/website%20pdfs/Charvat_Interview_AEXmag_Oct2013.pdf

 

 

  

Turkish Knack

Mehmet making contact using a homebrew rig

Lots of great homebrew videos from MehmetTB5X:
https://www.youtube.com/user/pashanline/videos

And he has a really nice web site:
http://www.tb5x.com/
Google Chrome does a pretty good job translating from Turkish.

DL1DN's First Homebrew Contacts with a BITX40

FB!

Nightmare Turns Real: "Rig Here is a Raspberry Pi OM, and I'm listening to you with my Dongle..."

As with many other nightmarish things, this one was launched at the world on Halloween. It all seems a bit flaky, but we knew this was coming.  Don't complain to me about the lack of low-pass filters, SSB testing on 7.000 MHz,  or the rather nebulous identity of the creator.... I'm just the messenger here.  And remember that I am a HARDWARE Defined Radio,  Discrete Component,  "Menus are for Restaurants" and (now) "Pi's are for eating" kind of ham. 

Here it is:

http://www.rtl-sdr.com/transmitting-fm-am-ssb-sstv-and-fsq-with-just-a-raspberry-pi/

 

CB to 10 Conversion? The Radio Gods Seem Ambivilent

A lot of trouble can begin with a 5 dollar purchase, as I found out after I bought a nickel bag of CB at a hamfest. 

The embarrassing little Good Buddy appliance has been hidden away in my junkbox for a while.  I pulled it out after watching Pete's videos about the conversion of his Ten-Tec Model 150A commercial rig.  I thought perhaps I could use a little DDS or PLL board to bring that CB rig onto 10 or maybe even 12 meters.  

The first thing I noticed when I opened it up was the smell -- there was a very strong chemical electronic smell.  It was as if components and wires and adhesives and PC boards had been venting inside that case for several decades.  This wasn't that pleasant electronics smell that you get from a Drake 2B or a DX-100.  No, this was different.  It gave me a bit of headache.  That's a bad sign.   I began to wonder if the Radio Gods might be sending me a message. 

But then I found this very cool conversion site:
http://www.jcoffman.net/WB5RUA/10_meter_AM_conversion_w_Photos.html

Wow, a few snips, a few jumper wires on the PLL board, and a few coil tweaks and that thing would be on 10 meter AM.  I also learned that the "Cybernet" board that was stinking up my shack was VERY common in CB rigs, so there is a lot of info about it on the internet.  This thing seemed to be crying out for a quick and easy conversion to ham-dom.  

So I don't know which way to go with this one.  I'm getting contradictory signals from the Radio Gods.  What do you guys think?  Garbage can or workbench? 

Rocket Knack in the Congo

This guy clearly has a rocketry version of The Knack.  Busted by the police for a match-stick rocket at age 17,  Jean Patrice stuck with his dreams of a Congolese space program.  Years later, when the rat flying in one of his rockets crashed and burned, he declared that the varmint had "died for science."  Indeed he did.  That is what I said about the lizards and mice killed in the payload chamber of my Astron X-Ray Estes rocket during the late 1960's.  A moment of silence please...

Imagine how difficult it would be to make any progress on something like this in the Democratic Republic of the Congo.  Godspeed Jean-Patrice! 

http://www.wsj.com/articles/one-africans-personal-space-race-turns-vermin-into-astronauts-1446239060

De-mystifying a chip -- Looking inside the 741 Op-Amp

Inside a 741 op amp, showing the die. This is a TO-99 metal can package, with the top sawed off

This is really cool and potentially life-changing for radical fundamentalist ludite homebrewers.  As our readers will know, my big objection to the use of integrated circuit chips is the fact that these little black boxes are in fact often, well,  little black boxes.  We don't know what is going on in there.  It seems to me pointless to shy away from the use of large black boxes (the extremely complex "radios" that dominate the amateur airwaves today) only to fill our homebrew rigs with smaller black boxes. 

But when we crack one of these boxes open and take a look at the transistors, resistors, and capacitors formed on the substrate, then diagram it all out,  I think the fog of mystery is blown away by a refreshing wind of insight and understanding.  We saw this happen on a much smaller scale when someone cut open an SBL1 mixer, but that wasn't an IC.  Ken Shirriff has now done this with the venerable 741 Op Amp.  And he did it with a hack saw.  Bravo Ken.  I can now in good conscience uses 741 op amps in my rigs.    

http://www.righto.com/2015/10/inside-ubiquitous-741-op-amp-circuits.html

Listen to my BITX17 Signal as Heard in France

I was talking to Alan F5LIW on 17 meters yesterday and he was kind enough to record a bit of my transmission and then e-mail it to me.  So here is what my BITX 17 sounded like in Dijon, France. I had the BITX17 going into the CCI EB63A amplifier running at about 100 watts into my Moxon antenna.  Thanks Alan! 

http://soldersmoke.com/N2CQRF5LIW.mp3