Marc Verdiell Has The Knack

Here is Marc Verdiell, the "Curious Marc" who repaired the Soyuz Clock (shown in yesterday's blog post).  

Really cool.  Many SolderSmoke fans will completely understand Marc and his passion for 
electronics. 

Taming Glitches in a Soyuz Space Clock (Plus -- Inside a Logic Chip and How Crystals Work)

Thanks to Bob KD4EBM for sending this.  

There is so much good info in this video:  They crack open a logic chip and look at the internal construction (it is entirely understandable by mortal minds).  They use cool test gear to troubleshoot the clock from a Soyuz spacecraft.  They explain very clearly the series and parallel resonances of quartz crystals, then display these resonances on a very nice spectrum analyzer.

The creator of the video is CuriousMarc.  He has many other interesting projects: 

https://www.youtube.com/c/CuriousMarc/featured

https://www.curiousmarc.com/ 

His bio is here: 

https://www.curiousmarc.com/about

One paragraph from his bio really resonated with me: 

Working on this old stuff forces me to deal with the very fundamentals of electronics (and electro-mechanics). The principles are exactly the same as today, but nothing is hidden in mysterious circuits - you can understand and fix everything. Years of Moore's law has sure given us gobs of transistors, oceans of memory and a glut of gigacycles, but many times, particularly in consumer hardware, these are simply used to cover up poor and inefficient designs - and resource devouring software. What Intel giveth, Microsoft taketh away, as they say. It often irritates me that my PC takes several seconds to react to a simple command, in which time it must have executed billions of unnecessary instructions and consumed a few gigabytes of memory, no one knowing exactly what for anymore. Nothing like this in old high-end hardware: designs are pure and efficient, and the lack of resources is compensated by engineering mastery and immense cleverness, which is a joy to reverse engineer. Not only does it teach us timeless electrical fundamentals and engineering tricks, but it also gives us a much better appreciation of today's tech. How did all the technology we take for granted came to be? It will make you a far better engineer and inventor if you take the time to be a thorough student of the inventions of your illustrious predecessors.

Global Collaboration: The uSDX -- A Multi-Mode QCX

Bill:

There is a new open source, home brew, multi band, multi mode QRP transceiver that grew out of the QRP Labs QCX. Through some serious magic it retains an efficient class E RF amplifier for sideband and digital modes. It crams impressive SDR capabilities into an Arduino. More info at https://groups.io/g/ucx/topics

The basic work appears to have been accomplished by Guido Ten Dolle PE1NNZ. It uses pulse width modulation of the PA supply voltage to transmit  modes other than CW while retaining class E efficiency and uses a direct conversion SDR receiver.

 https://github.com/threeme3/QCX-SSB .

There are several variants by different developers. I built a variant designed by Barbaros Asuroglu WB2CBA  

https://antrak.org.tr/blog/projeler/usdx-an-arduino-based-sdr-all-mode-hf-transceiver-pcb-iteration-v1-02/ that uses through hole components (mostly) and I'm pleased with it's performance. I also designed and 3D printed a case.

This has an interesting development process with contributions by many, including the usual gang of suspects: Hans Summers, Ashhar Farhan, Manuel DL2MAN, Kees K2BCQ, Allison KB1GMX and Miguel Angelo Bartie PY2OHH. I apologize to the many others whose names I didn't list.

The band switch multiband version by DL2MAN is even smaller, but with SMD components which I wasn't ready to tackle yet.

BTW - your podcast encouraged me to go in this direction. I built a BITX 40, a uBITX (sent you a pix of it in an old Heathkit Twoer case), U3S, QCX and now my first step from kits to built from plans.

73

Bob   KD8CGH

https://antrak.org.tr/blog/projeler/usdx-an-arduino-based-sdr-all-mode-hf-transceiver-pcb-iteration-v1-02/

Music Video -- "The Spirit of Radio" by Rush

Thanks to Thomas from The SWLing Post for putting this on his blog.

Andreas Spiess (The Guy with Swiss Accent) -- Workshop Tips

Thanks to Paul Taylor VK3HN for alerting me to the YouTube channel of Andreas Spiess.  There are lots of great projects there, including several videos on building an Oscar 100 ground station.  

In the video above, Andreas talks about his lab/workshop.  He is more focused on digital projects than I am, but I found many of his tips applicable to the analog world. And of course the more digitally oriented readers will find Andreas's observations especially useful. 

I was sold on this video when Andreas reached to his book shelf and showed us Tracey Kidder's "Soul of the New Machine."   That is the book that brought the word "soul" into the SolderSmoke lexicon. 

There are many great videos on Andreas's channel.  I found his Playlists page to be a good way to see the many different catergories of his projects: 

https://www.youtube.com/c/AndreasSpiess/playlists

Thanks Andreas. 

A Song Fom Dexter ZL2DEX

From a post on on "ZL Amateur Radio & Friends,"  in response to a complaint about the lack of activity (with apologies to Paul Simon):  

'50 Ways':

"Get on the band, Stan,
Trigger the mic, Ike,
Tap your key, Lee,
Listen for me.
Paddle the bug, Doug,
Watch the waterfall, Paul,
Just QSO, Joe,
when conditions agree."

73

Dex, ZL2DEX

Chuck Adams K7QO's AMAZING Lab Notebook

Thanks to Tony G4WIF for alerting me to this amazing (and free!) e-book by QRP Master Builder Chuck Adams K7QO: 

https://www.k7qo.com/lab.pdf

There is a lot of wisdom and tribal knowledge in that .pdf.  

Thanks Chuck. 

Mars is BACK! 2020 Opposition! Don't Miss it!

2004 

Sometimes waking up a bit earlier when the sunrise is coming later leads you to some interesting things.  

It was quite humid in Northern Virginia on the morning of 25 August 2020, but the skies were surprisingly clear.  I stepped outside at about 0500 local time, coffee cup in hand.  Venus was blazing in the east.  Then I saw this big very bright red thing high in the southern sky.   It seemed almost too bright and too high in the sky to be Mars.  But a quick check with Stellarium showed that it was in fact the Red Planet.  I pulled out my six inch Dobsonian reflector telescope and soon had Mars in the eyepiece.  

For the first time in many years I could see surface features:  It is springtime in the southern hemisphere of Mars, but the Southern Polar Cap (which recedes in the summer) was still very prominent (in my eyepiece it was near the top, as in the GIF above) .  I could also see an albedo (dark on light) feature below the icecap.

I went out again on the morning of 26 August 2020.  Again the Southern Polar Cap was very visible.  Below it, near the center of the disc,  I could make out a large albedo feature.  I am pretty sure that is Mare Erythraeum.  

Above is what Stellarium presented as Mars as viewed from Earth this morning. The Southern Polar Cap is much more prominent in my telescope (you can see it in the upper right in the image above).  The large dark thing near the center of the disc is Erythraeum.  In the Stellarium image you can see the enormous Vallis Marinaris canyon shooting off to the lower right (sadly I could not see this in my telescope). 

The GIF at the top of this post gives a much better view than I get with my little six inch telescope.  The GIF gives a good idea of what the albedo features and the ice cap look like.  

This was a great time for me to see these things.  I'm almost done with the second book in Kim Stanley Robinson's Mars Trilogy -- much of the story takes place in sanctuaries carved under the Southern ice cap, and in Hellas (which Robinson's colonists are filling with water).  During the 2018 Earth-Mars opposition a big dust storm made it impossible for me  to see anything on Mars; a similar storm takes place during book one of Robinson's Trilogy. And right now the Perseverance rover is on its way to Mars.  

This 2020 opposition will be the best one until 2033.  So don't miss it. 



Here is a good article on observing Mars during the current opposition: 
https://www.skyatnightmagazine.com/advice/skills/how-to-observe-mars/

Here are technical details on the 2020 opposition: 
http://www.alpo-astronomy.org/jbeish/2020_MARS.htm

To see what side of Mars is facing us at any time, use Sky and Telescope's Mars Profiler: 
https://skyandtelescope.org/observing/interactive-sky-watching-tools/mars-which-side-is-visible/#

Here is a very informative video about the 2020 opposition: 



And remember:  The Elser-Mathes Cup has still not been won.  

Great Video on PC Board Techniques, with a Focus on Surface Mount

Wow, lots of wisdom in this video from Leo Fernekes.  Great hints and kinks on prototyping with copper clad boards. I need a Dremel just so that I can make Leo's board cutter.  And I can see that I need some of that liquid flux and isopropyl alcohol. Surf boards and headers! Who knew?  Teflon coating for the wires -- gotta get it. Glad to see that Leo is also a fan of copper tape.

His emphasis on the importance of stage-by-stage construction and testing is right on the mark.  

My only disagreement with Leo is about his use of steel wool.  I've found that steel wool will inevitably cause little tiny "Murphy Whiskers" to float around your workbench. They will eventually settle onto the most inconvenient and damaging place on your board.  So I have banished steel wool from my workshop.  Those green, non-metallic Scotch Brite pads work just as well and don't cause shorts. 

Three cheers for Leo. He is based in Thailand.  He has an interesting background and some really amazing projects and insights:  

http://www.luminati.aero/leofernekes

http://www.fernekes.com/blog/

https://www.youtube.com/channel/UCe1bjEcBichpiAMhExh0NiQ/videos

Thanks to Tore LB4RG for alerting us to Leo's video.  

Experimental Methods Book on Clearance sale -- $20

http://www.arrl.org/shop/Experimental-Methods-in-RF-Design-Classic-Reprint-Edition/

And it includes a .pdf copy of Solid State Design for the Radio Amateur. 

Video on the Strange Tuning of the Radio Shack DX-390 Receiver

I'm more of a single conversion guy myself, but in working with the DX-390 I came to appreciate the benefits (especially regarding image rejection) of the double conversion technique. 

While working on the DX-390, I discovered that the BFO control on the front panel DOES NOT change the BFO frequency.  It was fun to try to figure out why the designers did it this way.  It does make sense once you consider the limitation imposed by that PLL main tuning oscillator that only moves in 1 kHz steps. I hope the video explains things.  

Here is the drawing I used in the video: 

And here is a drawing that shows how a single conversion superhet with a fixed or switchable  (usually crystal-controlled) BFO works: 

Earlier this month  I did a blog post on my repair of a broken DX-390: 

https://soldersmoke.blogspot.com/2020/08/fixing-up-radio-shack-dx-390-aka.html

Mike WU2D's Great Drake TR-3 Refurb Video -- Part 2

Mike WU2D made another very nice video about his Drake TR-3 refurb. 

He cracked me up when he noticed that one of the calibration oscillators was 30 Hz off.  "Let's pretend we care," said Mike.  Indeed. But it was probably wise to tackle this problem, given how upset modern hams seem to get with 30 Hz discrepancies.  Mike noted that the problem was casued by "aging cystals." Yikes! Another thing to worry about, along with the Southern Magnetic Anomaly. 

Once again Mike has added a useful term to our lexicon:   "The Dribble Method" of signal injection (or extraction):  Just wrap a few turns of insulated wire around the tube or IF can and inject or measure away.

Neutralization! Now there's a blast from the Thermatron past.  I haven't done that in a long time. I liked Mike's "reverse neutralization" method. 

Mike's video featured some real Boatanchor eye candy.   That Heathkit HR-10 receiver caught my eye, as did that HP signal generator. 

Thanks Mike.  One hand behind your back OM.