Harv's Minima

Good Evening Bill & fellow Solder-smoke friends,

 

Well, I’m following the pack. I began gathering items for the Minima Transceiver back in March 14. There had been a good bit of strong back-N-forth discussions on the Minima Blog about what works and what doesn’t work. Some circuit refinements had been agreed upon while other were left to individual preferences. So, I decided to just be silent an learn from the experts. As a result, I did several months of observing before I took the plunge. While my efforts are not nearly as aggressive as others, I decided to forge a much slower path to success.

In my own quirky way of doing things, I kitted each module, measured all the parts statically, laid out the components, and finally built & tested each assembly before going to the next.

As a result, the learning’s were great and the performance of each section equal or better than my expectations.

 

I went the Manhattan Style this time but,  I have purchased several sets of Minima PCBs to use in the future. As I see it, there is a lot more solder melting ahead.

 

Bill, building radios is NOT DEAD yet. That desire to get back to the golden days of home-brewing still lives on.

 

At the end of the Memorial Weekend, this is my current Minima progress…

 

·         Construction of all 3 Audio Stages now complete (see photos)

·         The Microphone Pre-Amp is now awaiting voice testing

·         Audio Amplifier and Final Amplifier have been tested together

·         The results of audio testing has been superb for all stages thus far

·         3 complete sets of Micro Relays have been order and I’m now awaiting their arrival

·         24 – various ferrite and powered iron cores arrived several weeks ago, these are the heart of the front-end RX/TX stages

·         100 - 20 Mhz. crystals have arrived and await characterization

·         25 - 8” Male to Male SMA Cables have arrived this weekend, will need to order 15 – 4” Male to Male SMA Cable Assemblies next

·         5 – 12” X 15” Copper Clad Boards have arrived this weekend

·         25 –J310 N-channel J RF Power FETs were ordered and arrived this weekend, these are used in the Mixer Stage

 

 

Final Audio Stage

 

 

Audio Amplifier Stage

 

 

Microphone Pre-Amplifier Stage (see microphone connector mounted at rear)

 

I’m ready to begin kitting the Side Tone Oscillator and RX/TX Relay Stages.

The largest and most intense modules are yet to be tackled.

The Bi-Directional Amplifier has 34 parts alone.  So far I have installed over 40 parts in the three modules I’ve completed…

I realize it is just a start but, I’m motivated to see this one project through to completion.

 

73’s & Happy Soldering

 

Harv -=WA3EIB=-

Albuquerque, NM.

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

Contact Reestablished with ISEE-3 Satellite

http://spacecollege.org/isee3/we-are-now-in-command-of-the-isee-3-spacecraft.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

SolderSmoke Podcast #161: Homebrew SSB: An Interview with Pete Juliano, N6QW

 

SolderSmoke Podcast #161 is available:

http://soldersmoke.com/soldersmoke161.mp3

26 May 2013

Homebrew Single Sideband -- An Interview with Pete Juliano, N6QW

-- Pete's background:  55 years in radio.  Boatanchors AND Arduinos. 40673 Mosfets.  Guitar!
-- A personal transition from CW to phone.
-- The importance of passing on "tribal knowledge."
-- What you need:  A library, tools, test gear and a junque box.
-- A new word in the homebrew lexicon:  Pete explains "noodling."
-- One stage at a time!
-- The attractiveness of standard circuit blocks (that work!)  
-- The importance of IF selection.
-- Building your own crystal filters is easier than ever.
-- Thinking (early) about the enclosure.
--VFOs, VXOs, and (gasp) Direct Digital Synthesis

Thanks Pete! 

Pete's Web Site:  http://www.jessystems.com/

Pete's YouTube Channel: 
 https://www.youtube.com/channel/UC4_ft4-oTdCMlWlL4XXHScg/videos


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

Meteor Shower Tonight

If the skies are clear, and if I can stay awake, I'll be out there looking for the new meteor shower. 

But there is no real need to go outside.  David, EA1FAQ has an SDR receiver tuned to a radar frequency in France.  You can see and hear the meteors as they create a path for the RF.  Very cool. 
Thanks David:

http://www.ustream.tv/channel/live-meteor-radar

You can also listen for meteor pings here:

http://spaceweatherradio.com/

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

Overheard at Dayton: Drake 2B Market Manipulation! (& Help needed with 455 kc IF can)

I received a very nice message from Preston Douglas.   Conveniently, he is an attorney, and I have asked him to stand ready to defend me in court should I ever be accused of manipulating the markets for Drake 2-Bs (and perhaps the market for SSDRAs). 

Can any out there help Preston with his SX-110 455 kc IF can?
 

May 20 at 3:38 PM

Hi Bill,

 

I enjoyed #160, even though I heard those talks, live at FDIM. 

I thought you'd be amused by what I overheard in the flea market on Saturday in Dayton.  I was looking at a Drake 2B and Q multiplier being offered by a lady who said they were her father's.  They looked to be in pretty clean shape, though of course there was no way to know what was going on under the hood.  She was asking $200 for both, and said she was open to reasonable offers.  Now, I already have a 2B and haven't found any need for the Q multiplier.  And I had flown out to Dayton from NY, so would have had to ship the pair of boxes home--probably should have bought them anyway and sent them home by UPS for that kind of money.  

 

Anyway, there were two other guys looking at the 2B.  One said to the other that these were among the best receivers of the tube era, but that the prices had become inflated by this guy who does the Soldersmoke podcasts talking up the virtues of the 2B.  Couldn't help smiling at that.

 

As to the Hallicrafters SX-110 on the repair bench.  Well, I worked out a deal with a professional tech guy to trade him my non-working HP 8640b sig gen for some bench time on the 110.  He found that the first IF  transformer that I was having so much trouble aligning was non-working.  He had no replacement, so he bypassed the whole transformer with a cap to get signal to the next stage.  This is, of course, not a satisfactory solution.  And nobody has that IF can to sell.  I did read on another radio repair guy's web site  that he, too, usually stops working on a set with a bad IF can because repair is so labor intensive.  

Frankly, I don't accept that.  I mean what's inside there?  A couple of coils and some open silvered mica leafs. So, I plan to remove the can, open it, and fix it.  According to the Internet, the built-in caps on these cans become defective and need replacement by modern capacitors.  Or, maybe a wire is broken off.  Before I do anything, I am going to see if that transformer is really unable to peak at 455.  Anyway, maybe I'll get some time to mess with this radio over the holiday weekend.  

 

One of the guys (or was it you?) recently said he builds 'em, makes a few contacts to prove they work, and then puts them on a shelf.  Then he builds another one.  It's like that sometimes.

 

PRESTON DOUGLAS

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

Latest Project: 17 Meter Moxon

17 Meter Moxon by AE6AC

That's what I have in mind.  I ordered four fiberglass "crappie" poles yesterday.  I have a tripod for the roof.   What should I use to spin this thing around?  A TV rotor is an obvious solution, but the last time I used one it didn't hold up too well.  There is always the Armstrong method...  

Here's AE6AC's site:

http://www.moxonantennaproject.com/ae6ac/ae6ac.htm


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

SolderSmoke Podcast 160: Special Four Days in May (FDIM) issue

   

George Dobbs, G3RJV

SolderSmoke Podcast #160:

http://soldersmoke.com/soldersmoke160.mp3

Bob Crane, W8SX, was out at the Four Days in May event and did an excellent series of interviews with the guys who made presentations:
 

Harold Smith, KE6TI
    Many Ways To Homebrew
 

Chris Testa, KD2BMH 
     Battery Powered Software Radios:
   Having your cake and eating it, too
 

George Dobbs, G3RJV 
    The Classic World of the Regenerative Receiver
 

Gary Breed, K9AY 
     Why Does My Rig Have a Receive Antenna Jack ?
 

Craig Behrens, NM4T 
    The Great Arduino, JT65 and Rebels Caper
  High adventure with new radio paradigms
 

Dave Cripe, NM0S 
     PoW QRP

 
-------------------------------------
 
VIDEOS OF THE PRESENTATIONS ARE HERE:

http://www.ustream.tv/recorded/47599691


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

Message in a Bottle -- Beacon in a Bottle

Wow.  Very cool.  Don't get hung up on the legalities or the environmental consequences.  Just enjoy the simplicity and the technique.   All the details are on this very nice Italian site.  Google will translate it for you, but the pictures and the schematic tell most of the story.  Bravi!   

http://air-radiorama.blogspot.it/

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

FDIM Midnight Mojo Ceremony (Tuna Tin 2)

Tyson Tuna Tin Two

An important message From Rex, 
Transcendental Titan of the Tuna Tin Twos:

 --------------------

Fans of the Ancient Sacred Relic,

If you have a little QRP rebel in you, like me, and are a fan of Ancient Sacred Relic, i.e. The Original Tuna Tin 2 transmitter, and all things housed in round metal containers usually designed for fish products and pineapple, and maybe cats if VERY thoroughly cleaned, then you might want to bring your Tuna Tin 2 rig to FDIM!

Around midnight, after the scrum leaves the FDIM Club night gathering, there will be a Tuna Tin 2 Midnight MOJO ceremony! THE one and only ORIGINAL Tuna Tin 2 transmitter will be on hand for this solemn occasion where major QRP MOJO is transferred from the Ancient Sacred Relic into the tuna can inductees in attendance. Admission is free but you MUST bring a MOJOee tuna can housed rig for entrance to the ritual.

NO rectangular or mint tin equipment will be admitted!! NO unaccompanied minors OR adults OR adults who act like minors will be admitted.

TT2 QRP MOJO will be transferred....FUN will be had.....PRIZES will be raffled off!

If you think you might like to be there for the Tuna Tin 2 Midnight MOJO ceremony remember to pack a tuna can or reasonable facimile (307 (3 + 07/16" diameter) industry standard 2 piece or 3 piece can) housed TT2 style rig in your travel bag!!

REMEMBER: NO rectangular or mint tin equipment will be admitted!! You must have a TT2 inspired rig in you personal possession to gain
admittance! NO exceptions!!

Respectfully submitted,
Rex  W1REX  The TUNA Tinman!
--------------------

 

I will not be at Dayton, but I might be able to lend my TT2 (seen above with Tyson) should some worthy radio amateur wish to participate in the midnight ritual.  Time is short, so if you are interested,  send me an e-mail explaining why you are worthy. 

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

HOMEBREW ETCHANT!

http://hackaday.com/2014/05/08/testing-the-efficiency-of-pcb-etchants/

This is great. We can add this to the list of kitchen and household products useful in our kind of projects!  Desitin for heatsink compound!  Breadboards for breadboards!  Now this!

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

Parts Cost for BITX in India: $5 US (that's buying all the parts!)

I knew that in India you could build a BITX for a few bucks, but I thought that this cost estimate assumed a fairly well-stocked junk box.   Not true!  This morning an e-mail from Farhan points out that even if an Indian ham has to BUY all the parts, he can get all of them for the equivalent of 5 dollars U.S.:

"Less than half a cent per resistor, less than a cent per capacitor, two cents per npn transistor and 50 cents for the IRF510. We use 'tv baluns' and tap washers for coils."

And, from the original BITX design page:

 "The purpose is to address the need among Indian hams in particular for an SSB rig that is easily and cheaply built. My original aim was to keep the price under Rs. 1000. The current design brings the cost to well under Rs.300 (less than 7 dollars)."

Now, when you are talking to someone using a new $10,000 Yaesu/Icom/Kenwood rig, it might be a bit unkind to mention that your rig can be had for $5. 


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

The Guy who Invented the LED

I'm a big fan of Ira Flatow's "Science Friday" radio program (recommended!)
This week, while digging through the archives, I found this gem:

http://www.sciencefriday.com/segment/10/12/2012/fifty-years-ago-a-bright-idea.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

Bert's EMRFD Direct Conversion Receiver

Very nice Bert.  Sounds great.  I like the pill bottle coil core.  Lew McCoy used them in his designs. I do think that air core coils do provide better stability than ferrites or iron powder.   I kind of like the SW broadcast background music.  I also like the internal 9V battery.  Glad to see someone else resurrecting an old DC RX project.  


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

VFO for BITX 20/40

Here's the VFO I use in my BITX 20/40.   IF is obviously 11 MHz.   VFO normally tunes 3697-3859 kHz for 40 meters.  Switching in that 220 pf cap lowers the range to 3292-3189 kHz for 20 meters.  It workd very well.   The coil is wound on a cardboard tube from a coat hanger.  I will put this in the appropriate file on the BITX group site.    I like the 20/40 band combination:  Good DX possibilities on 20, with provisions (40!) for the low sunspot counts to come.

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