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Sunday, May 25, 2025

HCJB is now in Western Australia. In "The Kimberly." And VK6JMS can use their antenna.

I grew up listening to HCJB's shortwave broadcasts from Quito, Ecuador.  Fast forward to the present:  This week I have had two radio contacts with Nic VK6JMS.   His callsign indicates Western Australia.  I assumed he was in the Perth area, but no, he is in the northern part of Western Australia, in the area known as The Kimberly.  Look on the map for the place called Kununurra.  That is where he is.  


Here is Nic VK6JMS's QRZ page: https://www.qrz.com/db/VK6JMS  He has access to some really fantastic antennas.  In his page he refers to them at TCI antennas.  I looked them up: 

 A TCI dipole array refers to a specific type of antenna system designed and manufactured by SPX Communication Technologies, a company formerly known as TCI. These arrays are typically used for high-frequency (HF) radio broadcasting and communications, and they are known for their ability to achieve wide bandwidths and efficient radiation patterns. 

https://www.antenna.be/tci-611.pdf

https://www.antenna.be/tci-613.pdf

---------------------------------------

These antennas are used for the SW broadcasts: 

Since 2003, Reach Beyond (formerly HCJB) has been transmitting from our Broadcast Facility in the Kimberley, in far north Western Australia, to the Asia Pacific region through shortwave radio, and currently broadcasts programs in 25 languages.

Founded in 1931 as radio station HCJB in Quito, Ecuador, Reach Beyond is now a global, partnership-driven ministry. Many people know us as the shortwave ministry that originated in Ecuador which went on to establish hospitals and medical clinics in Quito and Shell. Today the visionary “madness” of our founder Clarence Jones and his band of missionary pioneers lives on around the world. 

Here in Australia, Reach Beyond carries on that vision through its radio broadcast ministry. Our shortwave facility is uniquely placed in Australia to deliver powerful messages of hope to remote and isolated communities throughout the Asia Pacific region.  https://www.reachbeyond.org.au/on-air/

-----------------------------

One thing I noticed about Nic VK6JMS's signal:  there seemed to be a latency delay between when I turned the conversation over to him, and when he began to transmit.  I wonder if the Icom RS-BA1 remote station software that he is using might explain this latency. Any ideas on this?


Saturday, May 24, 2025

Ted KN4ZXG's FB SolderSmoke Direct Conversion receiver: "This project is the greatest gift to homebrewing..."


There it is, a thing of beauty.  The best part is that Ted built this receiver himself.  That is something that most hams NEVER do. 

Ted writes: 

This project is the greatest gift to homebrewing since I got interested in radio nearly a decade ago. Lot's of great projects out there but most go into a mysterious black hole of obsolete parts like the NE612 mixer that's hard to get, or even the LM386, which is plentiful but not as cool as this amp. Everything's divided neatly on it's own board and explained. The builder has wiggle room on the layout and ways to test each module whether that's with nice or budget equipment. Not only did I learn a ton about each stage, but also about making RF probes and making use of my modest but super useful equipment like the Nanovna. Although there were no mysteries, it all comes together to make magic. If you know stuff, you can do stuff! Thanks again de KN4ZXG, Ted.

While he has some great plans for modifications and improvements, at this point I think Ted should follow Farhan's advice and spend some time just listening to the receiver that he has built. Direct conversion receivers sound especially good. It is as if they are closer to the ether.

Here are some clips of Ted's receiver in action:

 

Congratulations Ted.  Welcome to the Hall of Fame.  


Friday, May 23, 2025

G0UPL at Dayton: SSB for the QMX, and Thoughts on Homebrewing

 
Click on the diagram for a better view.

Listen to the interview here: 


I think this is what Grayson was talking about when he said that Hans is a genius, and that his SSB project for the QMX was very complicated.  On his website Hans says as much:  "This is a very complex project."  Indeed it is.  Just take a look at the bloc diagram above.  This is not for the faint of heart.  In this interview, he talks about a full year of intense work on SSB for the QMX.  Wow. 

I think Hans makes some good points on why we still homebrew.  I liked his fish analogy:  we can buy all the fish we want at the supermarket, but people still go fishing.  Why? Because they like fishing.  

I'm not too sure about "the IKEA effect."  He seems to be saying that people derive homebrew-like satisfaction from assembling IKEA furniture.  Well, maybe some people do, but I think this is a long way from what we would consider true scratch-built homebrew.  Dean KK4DAS, for example, recently observed that he assembled two IKEA tables, but that this assembly does NOT make him a carpenter.  This is related to our discussion about the differences between ham radio kits and true homebrew:  IKEA flat packs are like the kits.  I think Hans is right about the pride and satisfaction that people get from building their own radio gear.  

Thanks to Hans GOUPL and to Bob W8SX for doing this interview. 

Thursday, May 22, 2025

Mitch NK3H's FB SolderSmoke Direct Conversion Receiver -- "Incredibly satisfying!"

Wow, Mitch NK3H has built a really nice receiver. (He says it is not pretty, but those of us who have built one or who are in the process know that it looks great.) The SSB really sounds good also. 

Mitch writes: 

It's not pretty but it works! Incredibly satisfying. In answer to the questions, (1) though I 'd built a few small Manhattan style boards (e.g., Michigan Mighty Mite) this was more complicated. I've been using W1REX's island cutter to create isolated areas on the copper clad board, rather than pasting on pieces of circuit board. But the islands are a little small for as many as four connections on one island, as in most of the transistor bases. Inevitably a component lead would inadvertently contact the ground plane and all bets were off. Tracking down the shorts was challenging. (2) Once I got to the audio amplifier board I carefully laid out all of the components before starting to solder. But as I finished each stage and was ready for the next, I always seemed to be missing a resistor or two. I'd search the desk and the floor -- very frustrating. Turns out the speaker magnet was collecting and hiding the missing resistors. Lesson learned. (3) Next I'm hoping to build a transceiver. Still looking for the right project, probably a little more digital than this wonderful DCR.

Mitch obviously learned a lot during this project.  I had similar experiences with pads on the same level as the surrounding board -- I found that the 1 or 2 mm of elevation provided by the Manhattan pads prevented a lot of inadvertent shorts to ground.  And I too "lost" (temporarily) a lot of components to the magnet in the speaker.  

Good luck with the next projects Mitch.  With the Michigan Mighty Mite and the DCR under your belt you are ready to go.  Maybe a Double Sideband transmitter to go with the DCR? Or, as you said, perhaps something more digital.  There is a lot of good ham experience with the Si5351 digital VFOs.  Or maybe even an SDR rig.  

Thanks Mitch.  Congratulations and welcome to the Hall of Fame. 

-----------------------

Join the discussion - SolderSmoke Discord Server:

https://discord.gg/Fu6B7yGxx2

 

Documentation on Hackaday:

https://hackaday.io/project/190327-high-schoolers-build-a-radio-receiver

 

SolderSmoke YouTube channel:

Wednesday, May 21, 2025

Grayson Evans KJ7UM Interview at Four Days in May at the Dayton Hamvention 2025

 

LISTEN TO THE INTERVIEW HERE: 


Grayson said quite a lot in this short 4 minute interview: 

-- At FDIM he was selling his wonderful book "Hollow State Design for the Radio Amateur."  Buy one here: https://www.ermag.com/product-category/books/ 

-- Grayson was also selling a Thermatron version of our beloved Michigan Mighty Mite transmitter.  It is crystal controlled for the 40 meter band, but the Color Burst Liberation Army approves! Here is a wonderful video on this rig:

And be sure to watch Grayson's excellent course on Thermatron Homebrewing: 

-- Asked why someone should build with tubes when so much good solid state stuff is available, Grayson makes some especially excellent points:  The solid state gear is often filled with mysterious little black boxes -- we often don't really know what goes on in there.  Thermatron construction provides a break from complicated SDR nonsense "that is not really radio."  That last comment will generate some criticism, but not from here.  I think Grayson is right,  He earlier expressed admiration for complex circuitry, but he also rightly defends simple, understandable rigs.  

Here are Grayson's Technical Documents (a real treasure trove):  https://kj7um.wordpress.com/

Three cheers for Grayson.  And thanks to Bob Crane W8SX for doing this interview.  

Tuesday, May 20, 2025

Bill K7WXW's FB SolderSmoke Direct Conversion Receiver


This is a very nice build.  Bill K7WXW fought a long battle to get this receiver working, and -- more importantly -- to understand why it is working.   

Bill writes: 

  1. The cycle of design, sim, build, debug, update, repeat can teach you a lot.


FB Bill.  Welcome to the Hall of Fame! 




Join the discussion - SolderSmoke Discord Server:

https://discord.gg/Fu6B7yGxx2

 

Documentation on Hackaday:

https://hackaday.io/project/190327-high-schoolers-build-a-radio-receiver

 

SolderSmoke YouTube channel:

Monday, May 19, 2025

Hall of Fame: The SolderSmoke Direct Conversion Receiver -- 80 Completed Receivers, 7 Honorable Mentions, Built in 15 Countries -- Many More Receivers Being Built.

WA1MAC's Receiver

Please let us know if you spot any errors, or if we have inadvertently missed anyone.  Don't worry about being late to the game -- the challenge continues.  All of the info is still available (see below). 

As of June 18, 2025  1049Z:

So far 80 completed receivers, with 7 honorable mentions.  Receivers built in 15 countries.   

NE3U (KY4EOD)  Matt 
KQ4AOP       First ham signals ever heard! 
N9TD             Derek
AC3NG          Ryan
VK3TPM       Peter Marks  
W4KAC         Ken 
W4KAC         Ken built a second one! 
N2EPE           Erik
VA3NCA        Wayde    
KI5SRY          Mark -- Gears on PTO screw
 
KA1MUQ       Frying pan receiver
AA1N              Adam
ZL1AUN         Aaron -- Using SSB transmitter
W8UC             Never before homebrewed. 
VK4PG           Phil -- Nice case, "really pleased"
G7LQX           Working well, video of CW and SSB. 
KE2AMP        John     Spring on PTO screw -- great
N9SZ              Steve  nice receiver
KD9NHZ        Piotr  Nice one
KE8ICE          Calvin, Very cool receiver. 
 
WV3V              Jayson!  Got it done!
GM5JDG         Martin.    
KF8BOG          Jim:  A long struggle, but success.  
Chris Wales    Fantastic video.  
YD9BAX        Wayan! Homebrew transformer! 
N0NQD        Jeff 
WN3F              Roy -- Made new stickers! 
AB5XQ            Bill  
KB7ZUT          Andy  
AA1OF            Jer

VictorKees        Holland
KC9OJV           John -- Manhattan-style convert
WZ5M              1, 2 or maybe even 3 receivers!
K1KJW             Jim in Vermont
KC5DI              Dallas -- friend of WZ5M
Gary                 Australian -- Wooden PTO form
LU2VJM          Juan in Argentina
K1OA               Scott "Most fun in 50 years"
KC9DLM         Ben -- Had EFHW problems
PH2LB             Lex  Yellow, Glue Stick

AI6WR             David
G6GEV            Dave (It was a blast!) 
KC1ONM        Wayne  MakerLabs NH
KB1OIQ          Andy    MakerLabs NH
KA1PQK         Jay       MakerLabs NH
W1TKO           Mike    MakerLabs NH
K5KHK            Karl
SM0TPW         Mikael
KI7LKB           Brian (coat hanger tube)
M6CRD            Chris

W2DAB           Dave in NYC
W4JYK            Wes of VWS
KA4CDN          Mike of VWS
M7EFO             Adrian 
VK5RC             Rob
KD8KHP          Dave
VK1CHW         Chris
KA0PHJ           Brian
W0IT                Louis
W1PJE             Phil

W2AEW           Alan
KN6FVK          John (Barkhausen-Be-Gone Spray) 
VU2JXN           Ramakrishnan
AA0MS            Doug 
9V1/KM7ABZ   Paul in Singapore
VK2BLQ          Stephen
N3FJZ              Rick
Daniel               VE5DLD
Student 1          Student of VE5DLD
Student 2          Student of VE5DLD

Student 3         Student of VE5DLD
K7WXW          Bill 
NK3H               Mitch
KN4ZXG         Ted
WA1MAC        Paul
N4AVC             Chuck 
K3IY                 Kevin
N6ASD             Ashish in Bangalore
W1DSP             Rick
WD4CFN         Steve
-------------------------
Honorable Mentions: 

*AA7U            Steve No PTO
*VK7IAN        Ian -- No Manhattan boards 
*KC1FSZ        Bruce's build on a PC board
*CT7AXD       Graham -- different AF amp
* DL1AJG      Andreas 
* Matthew      Student of DL1AJG
* Arash           Student of DL1AJG 
-----------------------------------------

Candidates for the Hall of Fame: 


SA5RJS              Rasmus
KA9TII               James
AA7FO              Chuck 
VA3ZOT           Tony  Surface Mount -- Honorable Mention? 
KM5Z              Mike Yancey
AB2XT             John (Done, just need the video)
KO7M              Jeff (Piper Cub)
KD4PBJ           Chris
VU2TUM         Puneit Singh

For more information on how you too can build the receiver: 


Join the discussion - SolderSmoke Discord Server:

https://discord.gg/Fu6B7yGxx2

 

Documentation on Hackaday:

https://hackaday.io/project/190327-high-schoolers-build-a-radio-receiver

 

SolderSmoke YouTube channel:

Daniel VE5DLD's FOUR FB Saskatchewan SolderSmoke Direct Conversion Receivers


Daniel VE5DLD is a teacher in Regina, Saskatchewan, Canada.  Back in early 2023 several lucky students joined him in building the SolderSmoke Direct Conversion receiver.  We had asked people to build the receiver -- we wanted to test the design before asking the local high school students to build it.  Daniel and his students came through for us, and ended up having far more success than we did.  Congratulations Daniel!  Welcome to the Hall of Fame. 

Daniel wrote: 

Hi Bill!  Yes, I had my own DC Receiver that I use every so often for fun and 3 built by my students.  All working.  We didn't get any video because we just finished the school year and the kids left, but I've kept in contact with them and they told me they have been able to receive signals from their homes.  The kids developed excellent troubleshooting skills gained large amounts of confidence in their ability to fix things.  Over the next year, my students told about fixing their gaming consoles and fixing problems in their parent's electronics.  They are certainly no longer afraid of opening something up to see what is going on!  And that's what makes me the most happy!  Yeah, you can just recognize myself and only mention that 3 students were able to build DC receivers.

And yes, the Michigan Mighty Mite was a fantastic gateway to home brewing!

Thanks for thinking of me and my students!

73
Daniel D.
VE5DLD


On June 19, 2023,  Daniel wrote: 

We got everything going and all 3 students now have receivers capable of inhaling RF.  We 3D printed some knobs and hot glued them.  We took one outside but didn't hear any signals.  Mid afternoon is not good for 40m.  We will try again later this week and I'll bring my KX3 to make sure there is a single for them to listen.  This issue on that last radio was an improperly installed J310.  The angle is was installed hid the problem well!  Here are a few pictures of the completed rigs. 

Back in 2015, Daniel built a Michigan Mighty Mite.  I was pleased to be reminded that I had sent him the crystal.  Go CBLA!  For more info on Daniel's transmitter see: 

Thanks Daniel! 73  
___________________________

Join the discussion - SolderSmoke Discord Server:

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Documentation on Hackaday:

https://hackaday.io/project/190327-high-schoolers-build-a-radio-receiver

 

SolderSmoke YouTube channel:

Honorable Mention: Andreas DL1AJG's THREE SolderSmoke Direct Conversion Receivers for Biologists

 

Andreas DL1AJG was another of those intrepid hams who,  in the dark of winter 2023 took up the SolderSmoke Direct Conversion Receiver Challenge in order to test our receiver (before we pushed high school kids to build it).  Andreas came to the task with a lot of useful teaching experience. At the time he was an academic  biologist and had been teaching a course called "Applied Electronics for Biologists."  See: 

https://soldersmoke.blogspot.com/2022/08/can-biologist-fix-radio.html


Some of Andreas's students

I put these receivers in the "Honorable Mention" category only because they deviated a bit from the basic schematic:  they used an indoor ferrite antenna, had an RF amplifier ahead of the mixer, and did not use a transformer in the AF amp.  But they are very clearly the SolderSmoke DC receiver, they succeeded in inhaling RF, and Andreas and his students built them to help us.  

Here is the schematic they used: 

Click on the image for a better view

Here is an e-mail exchange I had with Andreas when the scholatic dust had settled in June 2023: 

Dear Bill,

Please my apologies for my late update on our DCR project. We started with the course in the semester break and once the semester started only a handful of students were able to finish their receiver. A long shelf of shame .... 

Here is what we've got so far (those were finished at the end of April already). 3 nice DCRs completely sufficient to copy CW indoors without additional antennas starting from late afternoon. Strong stations can be heard all day. I found that coupling some 6m of wire with one or two windings to the ferrite core can boost the signal dramatically but can also increase noise. 

The PTO is based on your design (Bill Meara N26QR &  Dean KK4DAS) which was sparked by Farhan  (VU2ESE) , except that I've swapped the FET for a NPN. The input amplifier and antenna is from the JUMA active ferrite antenna by Matti Hohtola (OH7SV), the band pass filter is from Hans Summers (G0UPL), the mixer and the headphone amplifier is inspired by Pete Juliano (N6QW), you told me that the diplexer (as well as the whole DCR idea) is attributed to Wes Hayward (W7ZOI) and the perfect schematics of Rick Scott (N3FJZ) where crucial to get me started in the first place. I enjoy keeping track of original sources, as I would do in science. This shows that even little achievements are based on the ideas of many other great people -  and this is nothing to be ashamed of. 

This was a lot of fun! Thank You!
Best and yours sincerely,
Andreas

Wow, the direct conversion re-engineering of education continues, this time at graduate-school level with biologists in Munich!  Amazing.  

Andreas points out that his group was also plagued by semester-related problems that caused many additions to the German shelf of shame.  Let's hope that someday soon these builders will come to their senses and join the ranks of those who have finished their homebrew projects.  

Looking at the schematic (above) of Andreas's project, there are a couple of significant differences from ours:   

-- Their AF amp used a transformer-less push-pull design.  We had considered this but abandoned it thinking that it would be too complicated to explain the workings of this circuit to our students.

-- Most significant, is Andreas's use of a ferrite rod antenna and an RF amplifier.   I think a simple 33 foot quarter wave antenna (with a ground or a counterpoise) might work better.  But hey,  to  each his own!   The important thing is that a number of these receivers were successfully built.  They look beautiful.  

Congratulations to Andreas and the successful Munich homebrewers!  

-----------------------------------

Thanks to Andreas DL1AJG.  Welcome to the Hall of Fame.   

------------------------------------

Join the discussion - SolderSmoke Discord Server:

https://discord.gg/Fu6B7yGxx2

 

Documentation on Hackaday:

https://hackaday.io/project/190327-high-schoolers-build-a-radio-receiver

 

SolderSmoke YouTube channel:

Duct Tape and a Hero of Apollo 13


"If it moves and its not supposed to, you use duct tape."

Ed Smylie

https://www.nytimes.com/2025/05/16/science/space/ed-smylie-dead.html?unlocked_article_code=1.IU8.trNH.Cdleh2CdY7HB&smid=url-share

Sunday, May 18, 2025

Rick N3FJZ's Early Completion of the SolderSmoke Direct Conversion Receiver Challenge

 It was a cold day in early February 2023.  Rick N3FJZ had responded to an early version of the SolderSmoke Direct Conversion Challenge: 

I wrote: 

Rick N3FJZ has completed his the direct conversion receiver that we will soon be building with students at a local high school.   See video above. 


We are hoping that a number of people will build the receiver as we designed it.  Some folks have sent us versions of the receiver that they have built, but these versions often include significant deviations from our design, rendering them less-than-useful in checking our work.  Rick built it just as we prescribed.  His build is very useful in confirming the validity of our design.  So if you are working on one of these receivers, I would encourage you to -- for the moment -- dispense with innovations and build it the way Rick did:  as per the design we have been using. 

We know that our design is not perfect.  But we have decided to stick with it because it is very simple and very easy to explain.  Examples:  We know there is an impedance mismatch between the mixer and the AF amp.  But fixing this would introduce complexity that we want to avoid.   And the receiver works fine with the imperfection.   We know that a push-pull AF amp would probably work better than the one we have.  But we do not want to have to explain push-pull amps, biasing schemes, and PNP transistors in this short introductory course.  So we stuck with three common-emitter AF amp circuits and an 1K-8ohm transformer. 

Rick did a really excellent job not only in building this receiver, but also in documenting it.   His diagrams and drawings are really superb.  We will probably use these in our presentations to the students: 


We will keep all of you informed on the progress of this project.  We will begin this week.  But if you are still working on the receiver, please send us your work,  even if it comes in after we begin the course.  

Thanks Rick! 

-------------------------------------

Thanks indeed Rick.  Sorry it took so long to put you in the SolderSmoke Challenge Hall of Fame, but you are in now, and you definitely deserve it.  Congratulations OM.  

I especially like your finding the audio ourput transformer in an old transistor radio.  Too often we see builders quit after discovering that Mouser or some other supplier no longer stocks the needed part.  You show that homebrewers have other sources available, if they are willing to scrounge a bit.  FB.    I also liked the switch that helped compare the outputs of the two AF transformers.  Very useful.  

Thanks too for all the great videos and your really nice documentation -- we have used your work quite a lot. 

73 and welcome to the Hall of Fame! 

Rick N3FJZ

____________________________

Join the discussion - SolderSmoke Discord Server:

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Documentation on Hackaday:

https://hackaday.io/project/190327-high-schoolers-build-a-radio-receiver

 

SolderSmoke YouTube channel:





Saturday, May 17, 2025

Stephen VK2BLQ's Very FB EARLY build of the SolderSmoke Direct Conversion Receiver

 

This was back in the old days, long before we had Discord.  It was early 2023, and we were getting ready to start the Direct Conversion receiver project at the local high school.  I put out a version of the SolderSmoke Challenge:  I asked people to build our receiver and let us know if it worked for them.  Stephen VK2BLQ took us up on this and built the beautiful receiver you see above.  

Thanks Stephen.  Welcome to the Hall of Fame!  

Stephen wrote:  

Bill,


Don't worry, you are not alone out there.

Here is my build; sorry that the front panel is overexposed and hard to see, but it is plywood.

I did follow the schematic but due to the contents  of the junk box there have been some component changes.

The only thing that I had to buy was the 3/16 x 50 mm (2 inch) brass screw.

My calculations for the coils for the PTO and  BPF  were  a little  bit off necessitating padding down the PTO with a further 100 pF (easier than remaking the coil and mounting)  and removing a few turns from the T50-6 toroids.

Like other people have found: the audio takes off at full volume; I am thinking but not yet tried adding decoupling between R5 (15K) and C2(47 uF). It isn't the actual values of the electros as I had to use 100 uF so might be the audio output getting back into the earlier stage.

The tuning range I get is  our 7000 to 7200 KHz and some shortwave stations above and below, Turning the screw is a little bit fiddly, but once tuned the vfo is quite stable and the audio sounds good.

Best wishes,

Stephen

VK2BLQ

Designer: Douglas Bowman | Dimodifikasi oleh Abdul Munir Original Posting Rounders 3 Column