The Transistor that Changed the World -- the MOSFET

Another great video from Asianometry.  

My only quibble is that it kind of left unclear the differences between JFETs and MOSFETs.  After all, we still use both.  Note our beloved J310 JFET.  And the IRF510 is a MOSFET.  

Google's AI explains: 

A JFET (Junction Field-Effect Transistor) and a MOSFET (Metal Oxide Semiconductor Field-Effect Transistor) are both types of field-effect transistors, but the key difference is that in a JFET, the channel conductivity is controlled by a reverse-biased PN junction, while in a MOSFET, it's controlled by an electric field across an insulating layer between the gate and the channel, allowing for a much higher input impedance and greater design flexibility in MOSFETs; essentially, MOSFETs are considered a more advanced version of JFETs with superior performance in many applications like high-speed switching and integration into complex circuits. 

Tally Ho! Leo solders -- Aurora -- Satellites -- Meteors -- Tides -- Starlink

I've been following this YouTube channel, probably since early in the pandemic.  It is not about radio, but in this episode we see Leo actually do some soldering.  NOT BAD!   Lots of other related stuff.  

Here is the YouTube channel: https://www.youtube.com/@SampsonBoatCo

What Happened to the SolderSmoke Blog?

 

The conclusions of this article ring true, but I am not certain that changes to the Google algorithm, or the introduction of AI answers to Google queries explain the changes that are reflected in the above chart. 

Here's the article: 

https://www.bbc.com/future/article/20240524-how-googles-new-algorithm-will-shape-your-internet

Take a look at the traffic going to the SolderSmoke blog over the last year (see chart above). 

Something bad happened to us around April 15.  

What do you guys think?  What happened? 

MIT Looks at the Artificial Intelligence Podcasts of NotebookLM

https://www.technologyreview.com/2024/10/03/1104978/people-are-using-google-study-software-to-make-ai-podcasts-and-theyre-weird-and-amazing/

4Z4GE's Homebrew Tube SSB Transmitter from Israel, 1974

https://www.nzeldes.com/Miscellany/SSB-rig.htm 

Very cool. I like his description of how he found parts for this transmitter:  

The power amplifier tubes needed ventilation as well as shielding; that was always a challenge because I had no good source of perforated metal. The black sheet with the round holes actually came from the cover of a car air filter that I found in the trash.

There is a lot more interesting stuff on Nathan Zelde 4Z4GE's site: 

https://www.nzeldes.com/possiblyinteresting.htm

Thanks Nathan! 

Homebrew Receiver -- AG5VG's 20 Meter "Mythbuster" Receiver

Michael has the receiver done and is wisely heeding Farhan's advice about pausing to enjoy the homebrew sounds.  

I was pleased to see someone else using the FT-101 VFO.  Great piece of gear.  

On to the transmitter!  

Fernando's Rigs -- Vintage Ham Radio Receivers

Thanks to Rogier PA1ZZ for sending me this YouTube link.  It is a truly wonderful channel from Spain. Not only the Collins Gold Dust Twins, but also lots of great (and not-so-great!) older receivers.  SP-600s, S-38s,  Rhode and Schwartz rigs, lots of great stuff.  Go to the "Videos" link and enjoy the Thermatron goodness.   Thanks Rogier!  And thanks Fernando! 

 https://www.youtube.com/@jonglei

SolderSmoke Artificial Intelligence -- Where the AI Podcasts Came From

 

The aticle and the podcast (don't worry, it is NOT an AI podcast) explain how we were able to generate the AI podcasts we presented during the last two days. 

https://www.theverge.com/24249388/notebooklm-google-steven-johnson-vergecast

The audio podcast feature was introduced only ONE WEEK AGO!  Rarely have we been so close to the cutting edge!  

The product itself first launched in 2023 as Project Tailwind, and has since been rebranded and expanded in big ways. Just last week, the team launched Audio Overviews, which generates a podcast — with two chatty hosts, plenty of back and forth, and a truly remarkable penchant for the phrases “deep dive” and “buckle up” — based on the information you provide. It’s fascinating, it’s complicated, and it’s getting better really fast.

Thanks to Bob for alerting me to all this! 

AI Podcast #2: Here is Another Short Podcast ABOUT SolderSmoke.

Click here for the second "About SolderSmoke" podcast. 

 http://www.soldersmoke.com/About SolderSmoke 2.mp3

This one looks not at the SolderSmoke Daily News blog, but instead at the SolderSmoke podcast itself.

I was delighted to see the inclusion of Pete, Dean, Farhan and Mike Rainey!   This was really great.  

Look, it is not perfect.  There are errors.  But probably about the same number of errors that you would get from real, human hosts, right?    Voltaire told us not to let the perfect be the enemy of the good.  And I find this to be amazingly good. Look, it is so good that it is kind of scary, right?

Before you get too critical realize how this has been done:  I did nothing more than load the SolderSmoke Podcast Archive website into GPT-like model. Then I asked it to produce a deep dive podcast.  That's it.  About 5 clicks.  It developed the podcast in about 3 minutes.  I did the same thing yesterday but with the SolderSmoke blog.  And this is only the beginning.  

AI Podcast #1 -- A new (experimental) Podcast About SolderSmoke Daily News

GET THOSE SOLDERING IRONS HEATED UP!  WE'RE GOING DEEP TODAY, DEEP INTO THE WORLD OF HAM RADIO! 

Click here for the new experimental podcast: 

http://www.soldersmoke.com/About SolderSmoke 1.mp3

I am looking for comments on this.  What do you think?  

Please post comments below or send me an e-mail. 

Thanks and 73 

A Clean Vintage Ham Radio Transmitter: The Collins 32S-3

In an article on IMD and splatter,  tech guru Rob Sherwood noted that the cleanest tranmitter he had ever owened was the Colling 32S-3.   Here is the article.  https://soldersmoke.blogspot.com/2024/09/sherwood-its-time-to-clean-up-our.html

In it, you will see thar Rob has the spectrum anayser two tone test to prove his point.  

This got me wondering:  Why was the Collins transmitter so clean.   Today I looked at some ot the tech info on this rig.  I think I have found the answer. The Collins Collectors Association has a great page on the 32S-3: https://collinsradio.org/cca-collins-historical-archives/the-equipment-of-collins-radio/the-grey-boxes/32s-3/

The key lines are these:  

Click on the paragraphs or go to the link for a clearer view 

I think the explanation of Collins'32S-3 cleanliness is due to 1) Thermatrons in the final stages and 2) Negative feedback to take down any IMD products that might appear due to non-linearities in the finals.   

There is nothing magical in that technique.  Heck, we could homebrew that today.  We could build HDR stations (perhaps transistor-tube hybrids) that would be cleaner than their commercial SDR cousins. 

Ham Radio -- How To Build Stable Oscillators

Spasibo Vasily!  

Wow, thanks a lot Todd.   There is some great wisdom in your video.  You clearly demonstrate that it is possible to build your own stable LC VFOs.  Sure, for many the arrival of the synthesizer chip put an end to this kind of project.  But some of us still want to fully homebrew all the stages in our rigs, and not be dependent on mysterious chips and software written by others.  

I really liked the way Todd acknowedged the tremendous contributions of Wes, and Roy, and Rick and others. 

Of course, all of Todd's recommendations are right on the mark.  I have been following most of them (but I do fall short and occassionally use a Manhattan pad or two).  Todd even gets into the mysterious and arcane practice of boiling (three times!) toroidal transformers.  I do have a preference for air-core coils, but that boiling sounds like fun. 

One thing that Todd and Brad might also want to consider:   tuning linearity.  Too often LC VFOs end up having the frequency spacing very close at one end of the dial and very broad at the other end.  "Bob's Electron Bunker" provides some great tools for alleviating this problem:

https://soldersmoke.blogspot.com/2022/09/the-cure-for-frequency-bunching-up-in.html

Thanks again Todd! 

AG5VG's Homebrew 20 meter Superhet (with a CW rig Coming) (Video)

 Michael AG5VG finished this receiver last weekend.  He hopes to build a CW transmitter using an output of the Si5351.  Obviously I defer to Pete on that one.  Good going Michael.  I think it sounds great and looks even better.  

Vulnerable MOSFETS in NASA's Europa Clipper

 

Oh man, this is terrible.  Just months before launch of the Europa Clipper mission to Jupiter's satellite, they discovered that some of the MOSFETS in the spacecraft might get fried by the Jovian radiation.  1500 MOSFETS.  Ouch.  Details here: 

https://futurism.com/nasa-disastrous-flaw-spacecraft

"QRP Classics" The Book that Got Me Started in Homebrew

https://soldersmoke.blogspot.com/2022/09/fixing-up-old-homebrew-rig-barebones.html

A question this morning from Scott KQ4AOP caused me to Google this old book    On page 59 I found the article about my first transmitter.  Someone has put a copy of the entire book on the interenet.  Here it is: 

https://ham.v4.si/books/QRP%20Classics%20-%20The%20Best%20QRP%20Projects%20from%20QST%20and%20the%20ARRL%20Handbook.pdf

Sherwood: "It's Time to Clean Up our Transmitters"

 

http://nc0b.com/qst-article/NC0B-QST-Nov-2019.pdf

As an analog, HDR, discrete component, radical homebrew fundamentalist, obviously I have been concerned about all the hype about SDR.  SDR advocates often make it sound as if those of us who build with discrete analog components (crystal filters!) are hopless troglodytes, about to be thrown on the ash heap of radio history.  Or something like that.  They sort of imply that without the cleansing benefits of SDR, our signals will remain hoplessly dirty. 

I find it interesting that Sherwood concluded that the cleanest transmitter he ever owned was a Collins 32S-3!  He compared the two tone output of this old rig to that of a modern transceiver.  This was in 2019.  See above.  HDR wins. 

Don't get me wrong.  I want to clean up the signals from my HDR rigs.  But I am encouraged by Sherwood's remarks.  I do not think I will have to go SDR in order to have a clean signal.   I may just  do some two-tone tests on the rigs,  make some adjustments, and maybe build a class A Thermatron .1 kW linear. 

IMD in Transmitters -- Splatter? Or Signal Strength?

https://www.newsvhf.com/conf2024/PresPapers/WA1MBA-IMD_in_Transmitters.pdf

Here is a good (and very recent) article on IMD ("splatter") produced in transmitters. The focus is on VHF, but much of this is relevant to HF operators.  I found the footnotes on the ARRL "Clean Signal Initiative" to be worrisome.  They seem to just be assuming that all ham operators will be using commercial gear, and the "OEM" needs to be made to meet certain standards. This seems to leave the homebrewer out in the cold.  I can see where someday soon, the "standards" will exceed the capability of analog homebrewers.  That would be bad.  

The role that signal strength plays in the perception of "splatter" is often misunderstood by the "waterfall police."  We often we hear some irate waterfall policeman screaming that,  "You are 40 over and far too wide."   Here is a good quote from the article on this point: 

"If you have a calibrated spectrum display (as many SDR’s are these days), you can directly measure the level difference in dB. If it is 30 dB or more, then it could be an acceptably “clean signal”, even if it is bothersome. Most ham voice communication is conducted with less than 30 dB signal/noise, and in that case the unwanted IMD is buried in the noise."

And even in a low noise environment,  if the signal is 40 db over S9. that would mean the signal PEP is at -33dbm.  If the IMD products are 46 db down from the signal peak, that means your IMD products are -79 dbm.  That is S-8!   That signal will look quite wide in the waterfall, but it would be within FCC specs, right? The problem here is not so much distortion, as signal strength.  And let's remember that "legal limit" is usually a misnomer:  FCC regs require hams to use the minimum power necessary, not 1.5 kW on every single QSO. 

The Surprising Difficulty of Analog Circuit Chip Design -- AI to the Rescue?

https://www.youtube.com/watch?v=lNypq1XuZRo

Really interesting.  Why the design of the analog portions of chips is so much harder than the design of the digital portions.  

Great channel. 

Sony and the Transistor

 https://www.youtube.com/watch?v=7pi9k5n7Wrw

I found the comment about Sony's belief that NPN transistors are superior to PNP very interesting. 

IMD and Splatter

 

https://www.robkalmeijer.nl/techniek/electronica/radiotechniek/hambladen/hr/1988/10/page71/index.html

I think the point I was trying to make about the influence of signal strength is here:  

Referring to fig. 1C, note the high level of rf at the 3rd order level - typically 36-dB down. Consequently, there will be rf energy outside the normal 23 kHz passband that will be only 36-dB below the carrier peaks, or about one four-thousandth of the peak power. Not bad if the station is only 25-30 dB out of the noise, but very objectionable if it's 40-60 dB out of the noise.

I think it is supposed to read "2-3 kHz passband" vice "23kHz passband."

I guess the point is that QRP levels of operation can hide a host of ills.   IMD ills.  This makes me wonder about the cleanliness of my own signals.   I will have to do some more careful measurements. 

Ham Radio in the 1970s (and earlier, with some cool Jazz). What favorite rigs do you see?

Rogier PA1ZZ sent me this today.  I think I may have seen pieces of it before, but this restoration 

is really nice.  But ham radio seems to have been a lot cooler in California.  I don't remember it being so socially advantageous on the East Coast.   See Dilbert cartoon below. 

So many memories: 

-- The video opens with someone working on a QF-1 Q multipliers.  We have destroyed so many of these relics, in pursuit of the variable capacitors (which turn out to be not so good). 

-- A Drake 2-B on Field Day. 

-- An HT-37 in a shack.

--What looks like an HW-32a in a mobile rig. 

-- Maybe an HW-101. 

--  A BC-348. 

-- The ATV station with lots of homebrew gear was very cool. 

-- I also liked the single THERMATRON homebrew CW rig made from an old TV.  FB. 

-- The CW used in the video was all pretty good.  There was a lot of chirp.  This, of course, adds character to a signal.  FB.

After the video, they take a walk down memory lane, looking at ham radio magazines with some cool jazz playing in the background.  I saw a Swan 240 and a D-104.  The debauchery of the 1970s was evident on the magazine covers.  Even QST seemed to be caught up in this.  Check out the August 1975 cover of QST.  

Anyway, this video was a lot of fun.  Thanks Rogier!  

What favorite rigs do you see?   Make note of them in the comments. 

This video and the Dilbert cartoon reminded me of a discussion we had many years ago about THE KNACK: 

https://soldersmoke.blogspot.com/2008/11/cry-for-help-soldersmoke-responds.html

Excellent New Video from Grayson KJ7UM on his Thermatron version of the Michigan Mighty Mite

Here is a really wonderful video from Grayson Evans, KJ7UM, author of Hollow-State Design for the Radio Amateur.  

I really loved this video.  Throughout we see Grayson's sense of humor.  Early on he explains the differences between a tube (what remains from a roll of paper towell), a valve (like the plumbers use) and a THERMATRON (like a 6146).  Grayson is the inventor of the word Thermatron.  We should all pledge to use it whenever possible. 

Grayson's humor also shows up when describing the parts acquistion process for the Thermatron Michigan Mighty Mite.  He puls out a coil (a huge coil) and laments that it is not -- despite its large size -- sufficiently inductive. 

There are wonderful shout outs to SolderSmoke, to Electric Radio, to the Color Burst Liberation Army, to Pete Juliano,  and to Rex Harper.  

Grayson describes the utility of Rex Harper's Thermatron ME pads.  

During the video, Grayson actually builds the Thermatron MMM.  In under 2 minutes!  He then experiences the Joy Of Oscillation, or JOO as it has come to be known.  OM needs a contact -- listen for him on 3579.  He is calling CQ.  

Grayson talks about his book, Hollow-State Design.  I have a copy with me here at SolderSmoke Shack South in the Dominican Republic.  Great stuff.   The above link takes you to Lulu, where you can order the book.  You can also get it from Electric Radio Magazine here: https://www.ermag.com/product-category/books/

Thank you Grayson for bringing us this video, and so much more over the years.  And for giving us the very useful and fun word:  THERMATRON!  

Who can tell us more about Lovelock's homebrew shortwave radio?

"Three years earlier, Lovelock had listened on his homemade shortwave radio in Finchley to the 'beep, beep, beep' transmission of the USSR’s Sputnik, the first satellite that humanity had put into orbit. Now he was playing with the super powers."

From: https://www.theguardian.com/environment/article/2024/sep/05/gaia-theory-born-of-secret-love-affair-james-lovelock

A bit of a soap opera, but the radio question is, I think,  interesting. 

CuriousMarc Visits Cape Canaveral -- Lots of Space History (and some ham gear)

I like all the CuriousMarc videos, but I especially liked this one. Marc and company visited some of the very early launch sites and bunkers at Cape Canaveral.  If you thought Apollo tech was crude, take a look back at what they used in Mercury and Gemini.  Wow.  

I spotted two ham radio receivers.   In the first bunker at 10 minutes 28 seconds we see an old National HRO Sixty with the classic HRO dial, much like the one given to me by Armand WA1UQO. (Thanks again Armand!) Note how they attribute one of the early launch disasaters to two diodes in the power supply that shorted due to launch vibration.  I hate it when that happens.  

In the second bunker we see a Hammarlund HQ-140 at 19 minutes 7 seconds.  This was apparently being used as a Frequency Standard (or maybe a time standard?) perhaps receiving WWV at 10 MHz.  I note that the frequency knob shows it set for the AM broadcast band... 

How to Homebrew your own Transistors

No store-bought transistors for these guys -- they homebrew their own point contact transistors using a bit of Germanium from a diode.  This makes me feel like such an appliance operator.   

This video is in Polish, but The Knack is a universal language, and this guy obviously speaks it.  Turn on captions, then opt for auto-translate to English.  You will then get English subtitles and Bob will be your uncle.  

I really liked this one.  This fellow has obviously DONE this;  his video is filled with both practical tips and theoretical explanations.   He talks about the virtues of beeswax, and about how to borrow red nail polish to mark the collector lead.  FB. 

Here's the channel:  https://www.youtube.com/@Marcin_Marciniak

In their next episode they promise to build a radio receiver using the homebrew transistors.  That'll be great. 

Thanks to Marcin and company, and to Jenny List of Hack-A-Day who alerted us to this. 

Marcin is a ham  -- SP5XMI:  https://trafficlist.altervista.org/radio-officer-friend/marcin-marciniak/

But who is the fellow who built the homebrew transistor? 

Mr. Carlson Makes a Thermatron Power Supply for a BC-348

When I was 14, I had to make a power supply for a Heath HW-32A.   Mine ended up working, but it was nowhere near as nice as Mr. Carlson's BC-348 supply (shown in the video above).  I didn't have a sand blaster, nor a drill press, nor much of anything else, really.  

But hey, don't real boatanchor hams use Greenlee chassis punches?  What's with the drill press and the hole saws? 

Note that Mr. C takes care to make sure that the rectifier tube is in the proper angle FOR OPTIMAL VIEWING.  That's some serious attention to detail OM.  And whoa, DELICATE SURFACE MASKING TAPE from 3M?  Respect!  Also, era-specific looming material. 

His point about the importance of the cardboard washers in the power transformer was really useful.  I hadn't thought about that. 

Here are the two previous BC-348 videos: 

https://www.youtube.com/watch?v=nX87kwSshZ8

https://www.youtube.com/watch?v=Zqe6CBe0iGs

Thanks Paul! 

SolderSmoke Quiz Question: Who is the actor in this Bell Labs video?

He appears at 8 minutes, 17 seconds.  And he is somehow in the YouTube title frame.  I think I know who it is.  Any ideas?  (DON'T LOOK AT THE COMMENTS!) 

 

"Matter Waves" -- A 1961 Bell Labs Film

I continue to mine the AT&T video archive.  Here's a really wonderful 1961 film showing how particles really are waves also.   The simplicity of the gear that the Bell Labs folks used to demonstrate this is really admirable.  I would love to see the preceding film (the one that shows how light waves are really also particles). 

Arthur C. Clarke Talks about Satellites, SETI, Remote Work, and Wrist Radios (1976 Video)

He was, of course, right about the impact of satellites, but he was the inventor of the geo-stationary concept.  I wonder how he would react to the low-earth orbit Starlink system we are now using. 

He coments about how contact with extraterrestrial civilizations could come at any time, but notes that false alarms are common -- this made me think of recent explanations of the famous "Wow!" signal. 

His "Communicate don't Commute" idea seems to foreshadow the "remote work" via  Zoom that kicked in during the pandemic.  

And he talks about Dick Tracy-like wrist radios.  I sort of have one now (thanks to Elisa), in the form of my Apple Watch.  But it may be that putting a camera in there would be a bit too much... 

"The Far Sound" -- Bell System Video from 1961 -- Good Radio History (video)

This is a really OLD video, but there is a lot of great material here: 

-- Tubes.  (Valves or Thermatrons)

-- Coax.  

-- Frequency Division Multiplexing. 

-- Negative Feedback and the fight against distortion. 

-- Transistors and early experiments with semiconductors.

-- Fiber optics and Masers.

-- Satellite communications.

-- Early hopes for video communications.

The video is, by today's standards, extremely misogynist.  And the sound experiment with the poor woman wearing a male head was just weird.   But still, an interesting film. 

Thanks to Mark KM4GML for reminding us of this wonderful Bell Labs (AT&T) video archive. 

https://www.youtube.com/@ATTTechChannel 

 

Harry Caul had THE KNACK -- Movie Review -- "The Conversation" --1974 by Francis Ford Coppola (Harry Caul based on W3VCG)

 

I give it FIVE Soldering Irons! 

I found it on Amazon Prime.  The workshop scenes remind me of ham workshops.  The movie character Harry Caul was based on real-life Marty Kaiser.  Was Marty a ham? 

POSTSCRIPT (August 23, 2024):  Yes, he is a ham!   W3VCG!   FB.  Here is his web site: 

http://www.martykaiser.com/fbi1~1.htm

https://en.wikipedia.org/wiki/The_Conversation

http://www.martykaiser.com/odyssey2.htm

Thanks to Roy WN3F for reminding me to watch this film.  Roy found a clip that is reminiscent of hamfests: https://www.youtube.com/watch?v=joM5VDCIQg8

How Big is a Photon? (Video)

As I have mentioned in the podcast and in blog posts, I have a lot of trouble picturing HOW 20 meter photons somehow fly off my antenna.   I understand how EM WAVES are generated.  But there doesn't seem to be any corresponding explanation for how the photons are generated.  

This video looks at a related question:   How BIG are the photons of visible light?   I am not sure this is all correct (and neither, apparently, is the creator of this video) but it is very interesting.  

Comments are welcome.  

The Tropics Defined: Sun Directly Overhead on July 31 in Punta Cana DR

July 31, 2024  12:30 Local Time

Check out the shadow at my feet.  The sun is directly overhead.  This happens here on July 31, shortly after noon.  We define "the tropics" as the area of the earth at which -- as some point in the year -- the sun will be directly overhead.   Here we are at about 18 degrees North latitude, so for us, the overhead date is July 31.  We are definitely in the tropics.  A good graphical description of what is happening appears here: 

https://www.suncalc.org/#/18.5548,-68.3853,12/2024.07.31/12:37/1/3

A Wonderful Aeronatical Mobile Contact

 29 July 2024

20S 0943Z 0543L K8JSM/AM Sean, pilot on a 757/300. En route from San Francisco to Orlando with 246 souls on board, including a bunch of kids going to Disneyland.  Was 35,000 feet over Louisiana (12 miles East of Shreveport) when I first spoke to him.  (He had been in QSO with Andrew VK6IK in Western Australia.  I could hear Andrew also.) Sean was using the 400 W Rockwell-Collins transceiver on the plane (that's his picture of the control panel, above), with the antenna vertical in the back vertical stabilizer (rudder). I told him I was running 20 watts from a homebrew rig to a vertical ¼ wave ground plane antenna about 70 feet up; he speculated that the fact that we were both vertically polarized must have been helping.   Sean said he also pilots 767s transatlantic. 

I really had two contacts with him,   Around 0600 local he was calling CQ and no one was answering.  So I called him again and we continued:  I told him about the Aeronautical Mobile contact I had had from Samana.  I also told him about my contacts with MIR and RS-10 (and the RS-10 robot!) from the Dominican Republic 1992-1996.  I told him that Elisa had been present for many of the contacts with Norm Thagard on Mir station (Elisa walked in the HI7 shack at around this time – Sean said hello.)  Sean said he has been a ham for a long time – since before he was a pilot.  He has built a 2 meter “tape measure and PVC”  antenna.  I told him we have a little aircraft radio and use it to listen to the tower at Punta Cana airport, and to aircraft calling the regional ATC in Santo Domingo.  Sean says he too has a little airband receiver and often uses it to listen to airplane tower traffic.  Sean said the airline encourages this kind of contact because it is a way to keep pilots alert on long overnight flights (other pilots have other activities to do the same).  As we spoke he was waiting for a meal (salmon).  He mentioned that he could see the constellation Orion out the window;  I told him I had been looking at Orion in low in the East just before talking to him.  In the end, Sean  had to sign as the plane crossed into Florida and aircraft pilot duties took precedence.  

More info on Sean here: https://www.qrz.com/db/K8JSM     

Thanks Sean!

A Message from Walter KA4KXX -- On Bias Setting, the Joys of Al Fresco Rigs, Lawn--Sign Radio Base

 

Dear Dean KK4DAS:

...

3) Note that a rule of thumb I have used successfully in adjusting RF Power MOSFET

bias is to increase the voltage in 100mV steps, measuring the RF Output Power 

each time, and stop as soon as you start to see significantly diminishing returns.

4)  Although I did mention a plexiglass cover (the idea was from the Electroluminescent 

Receiver in photo below) in a 2017 entry I made on my QRZ page, I never built one, because I  have found a cover of any kind to be unnecessary and even detrimental based on operating portable outdoors in a public park with my rigs once every month for 10 years.  

From these experiences I have enjoyed the wonderment and respect I have received 

from fellow hams as well as passersby who have universally admired my creations. 

If the truth were known, my homebrew Alfresco transceivers might be the most 

photographed radios in all of ham history!  

Therefore, the only box I bring to my ham radio outings is for my lunch, because nobody

really gets excited about photographing just another box.

However, I do use plastic carrying cases per the photo for any rigs I carry 

in the trunk of my car.  If it rains, the top of the carrying case can be used as a 

temporary cover, so I know contacts can be made in a light rain because I have done it.

[Of course, credit card hams are not capable of operating portable even on a cloudy day

or their $$$$ radios would suffer from high humidity disease and need to be sent 

back to the offshore factory for $$$ refurbishment!]

5)  Lastly I will mention that I have never used any type of wood for a radio base because

wood is too heavy (and 1/8 inch aircraft plywood is too expensive), and the strength of

wood is not necessary to support a measly 5 pounds of electronic parts. 

Instead, per the photo, I have used Coroplast yard sign material (usually two sheets

with the channels crosswise then taped or glued together with the top covered using copper tape) common school science fair poster board, or good heavy duty cardboard such as from a TV set box.

Either light or heavy-duty double-sided tape and 4-40 or 6-32 nuts, bolts, and washers (sometimes oversized) are used to hold everything on board.  Occasionally L brackets, standoffs, hot glue, and foam or balsa wood support pieces are also utilized. 

In summary, keep up your good work as the new star on the Soldersmoke Podcast and 

please be certain Bill pays you as much as Pete.

72,

Walter

KA4KXX

Some Pictures of SolderSmoke Shack South

That's me at the operating position.   Window looks out to the terrace and to the ocean to the East, the  Mona channel.  The shack is on the top (seventh) floor. 

Here is the view from the terrace, looking South.  The big terrain feature is Cabo San Rafael. 

From the terrace looking North. 

Looking East into the morning sun 

From the terrace looking West. 

Antennas will go up there.  Perhaps solar panels too.  

A bog portion of the shack is a workbench with tools and test gear.  

Yesterday an old friend from Santo Domingo, Luis Ernesto HI8LEZ stopped by.  Thirty years ago we were pioneers in the use of amateur radio satellites from the Dominican Republic.  Luis Ernesto is in the book! 

SolderSmoke 252 Audio Podcast is Published

The delay was caused by my being at SolderSmoke Shack South and not having an Audacity audio editor in my ancient Chrome book.   Thanks to Dean KK4DAS for doing the editing, and for stripping the audio from the YouTube video.  I am getting a better computer so things should be back to normal soon. 

Here is the link to the audio podcast: 

http://soldersmoke.com/soldersmoke252.mp3

Are Hackers the Future of Amateur Radio? Thoughts from Lex PH2LB

Thanks Lex:  Your message reminded me of a comment sent to me on the YouTube channel.  The commenter seemed to criticize my use of a digital oscilloscope.  Well, the criticism came to me via the internet, computers, and Starlink, so, yes, there are great advantages to using new technology!  73 from HI7   Bill  N2CQR

Hello Bill and Pete,

On hackaday there is a post with the question : Are Hackers the future of amateur radio?

See: https://hackaday.com/2024/07/18/are-hackers-the-future-of-amateur-radio/ 

I want to share my thoughts on this.

 

Although the term "hackers" is only seen by the masses as a term for someone who gains unauthorized access to computer systems (it even appears in the dictionary that way), IMHO it is much broader. I always explain it as someone who is interested in technology and uses techniques to use things in a different way than what they where intended or to add new functionality to existing things. But also inventing new things, whether or not to satisfy his curiosity, or to learn new things in order to expand his knowledge or be able to make new things. 

With this in mind let us go back to the question: "Are hackers the future for amateur radio?"

I think that from the beginning of amateur radio, the OMs were a kind of "hackers" who satisfied their curiosity and tried things out by making things themselves. And I think it will certainly remain that way. The fact that we have started using more computer technology / digital things in our hobby is nothing but progress. You take technology as you can or want to use it. Think about the analog VFO from Bill and the Si5351 VFO from Pete, or petrol cars and electronics cars. Both have the same goal, just different tech. Or for example you can tighten a screw by hand, but you can also use a cordless drill. Do you have less technical skills? No, I don't think so, you are just more efficient, digital technology and computer technology have added efficiency to our hobby. And if other invent new things that we can use, who are we not to use those techniques to be more efficient our self or make new things?

Dan, KB6NU's put some nice HamRadio Hacking examples in his presentation (https://www.kb6nu.com/there-is-hope-for-amateur-radio/) like the SBITX (Full SDR with Raspberry PI), creating new firmware for Chinese ports, etc.  We could even return to the question discussed earlier on soldersmoke: Are radio hams 'makers'. 

And yes, the availability of off-the-shelf transmitters/receivers allows OMs, who are not so technically skilled or don't want to spend the time on it, to practice facets of our wonderful and broad hobby. So you don't have to be a "hacker" to enjoy our hobby.  And to all the (self-styled) soldering iron moral knights who criticize these OMs, take a look around your shack, you probably didn't (or even can) make everything yourself and once you have bought things. It could be that boatanchor, your  brass morse key or your first rig. And have you ever thought about you soldering iron, multi meter, magnifier lamp, wire cutters etc. . . Ok I'm just teasing now, but you all get the point. 

Most of all, aside from the question if hackers are the future of amateur radio, lets enjoy our great hobby and when you like to melt some solder . . . Just do it. 

73 from PA

Lex PH2LB 

SolderSmoke Podcast #252 -- First Podcast from SolderSmoke Shack South

For the moment this podcast is video only.  The video appears above.  Here is the URL for the video: 

https://www.youtube.com/watch?v=NeNTv3YjiHU  We will try to get the usual audio podcast version out soon. 

-- This is the first podcast from SolderSmoke Shack South:   Eastern tip of Island of Hispaniola.  Cap Cana, DR, 70 feet up, 1 mile from Mona Channel.  Seventh floor shack with view of the ocean.  Antennas:  Dipoles for now, maybe Moxons or Hex later. STARLINK

- The San Francisco case against me.  One guy thinks we DESERVE prosecution!  Get off of my lawn! 

Like the library cop on Seinfeld: https://www.youtube.com/watch?v=D9tP9fI2zbE

But one fellow wrote letter to the mayor asking for leniency.  Proposes "Bill Meara Day in SF." FB!  I fell victim myself this year:  Mike WU2D got me with WA1HLR on SSB video. https://www.youtube.com/watch?v=NLvCNJ_OnEc

-- Dean:  Fighting a spur in the sBITX.  Filters? 

-- Dean:  Exploring Class A, Class AB and the RD06HHF1

-- Dean: Extensive work on getting flat gain from FETs up through 10 meters. 

-hh- Dean and Bill:  OIP3 measurement and setting the bias on an RD06HHF1

-- Pete:  Discovers for all of us "RF Man"   In spite of all the CB stuff, he is the THE MAN!  On YouTube:https://www.youtube.com/@rfmanchannel6915

-- Pete fixes Dean's relay chattering problem: SUBTHRESHOLD CONDUCTION!  Yikes!  

-- Pete's refurb and rejuvenation of the Drake Twins, 

-- MXM news.  New docs, and ads from WD5L. All on the blog. 7030 crystals.  Why MXM? Chuck Adam's mods, Joh DL6ID's questions about VFO.  Yes!  VFO from RX.  Was Bruce Williams an early Swan Designer? 

-- Weird paradox with 25 MHz filter:  Low profile xtals have higher Q, but produce more rounded passbands.  Why?  I note that Minima's 20 MHz filter also had curved passband. 

-- Allison's wisdom on filters at higher frequencies.  The importance of physical layout.  Diodes in the dark!  It is indeed more difficult up there.  But don't let the perfct be the enemy of the good!

-- Is Bill  the only one to ever build a 10-15 Dual Bander using a 25 MHz crystal filter.  Why?  Farhan's Minima has a 20 MHz 6 pole QER crystal filter.  And it too had a rounded passband.  But it tooc WORKED.  

-- Did my receiver sound tinny due to rising frequency response of uBITX Rev 4 amp?  Yes! So I put in a  TJ DC RX Af amp.

-- Bill BLOWS UP a Tiny SA Ultra. Ooops.  But quickly got a new one from R&L Electronics.  Very, very useful.  I knew 25 MHz IF rigs were inferior, but by how much?  How much was the carrier suppressed?  Which filters worked better?  What was the opposite sideband rejection.  TinySA permitted measurement and comparison. 

-- Bill quit 15 meter SSB (for a moment) and went to the 1.22 nanometer band with a Wilson Clound Chamber.  Videos on the blog. 

SHAMELESS COMMERCE:  Thanks to new Patreon sponsors.  I am sending some additional video content to the sponsors.

MAILBAGg

-- Thanks to Bob Crane W8SX for FDIM interviews.  I will get them out! 

--Wes -- W7ZOI has a new TIA amp with variable gain on his web site: https://w7zoi.net/

-- Geoff N6GWB's Rad Receiver https://soldersmoke.blogspot.com/2024/04/the-rad-receiver-from-n6gwb.html

-- Dave K1KA sent Ensemble RTX SDR parts.   Thanks Dave. 

-- Chuck Adams AA7FO provided good background on my MXM rig, including the meaning of MXM (1990) . Again, great to hear from Chuck, a true homebrew hero.

-- Gerardo HI8P collecting info on the other HI8P, my friend Pericles (SK) 

-- Alvin N5VZH picked up a Silktronix CB VFO.  What to do? 

-- Jorgen SM4WWG listening from Sweden, and making PCBs.  FB! 

-- Mike WN2A  Wondered about opposite sideband rejection of MXM.  Not great. 

-- George WB5OYP loaned me a book from Elmer Bucher.  THE Elmer?   https://k9zw.wordpress.com/2020/01/24/on-the-origins-of-elmer-a-reasonable-theory/

-- Wes W7ZOI, Farhan VU2ESE -- Thanks for help on filter issue. Thanks too to Alan W2AEW and G3UUR

-- Josh G3MOT -- Nice message of support in our "struggle" with SF authorities. Going portable to Vancouver island in August.  VE7/G3MOT

-- Paul VK3HN -- Antipodean solidarity.  Thanks Paul. 

-- Rogier PA1ZZ -- great input and help. Thanks

-- Tony G4WIF reminded me of G3ROO's  parasets.  See Blog

-- Pavel CO7WT His experiences (building, freezing, heating) the VFO in the Jaguey DSB rig.

-- Grayson KJ7UM Sent latest ER with his Collins 51S-1 story. Thanks Grayson. 

-- Allison KB1GMX  Commiserating on higher freq crystal filters. Thanks Allison 

-- Wes W4JYK Notes that Dewey, Cheatam and Howe are based in SF. Can they help with sticky sticker problem?