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Wednesday, October 27, 2021

How to Listen with your TinySA


We don't get many chances to do hardware work on a piece of gear like the TinySA, but here we have one.  I mentioned this a while back:  Not only will the TinySA display the signals it detects, but it will also allow us to listen to these signals.  Very cool.  I am going to do this.  

Here is the link showing how to do the mod: 


All the cool people listen to classic rock with a TinySA: 

Tuesday, October 26, 2021

SETI, Proxima Centauri, The Parkes Dish, and Intermodulation Distortion?

 

https://www.sciencealert.com/exciting-mystery-space-technosignals-were-indeed-produced-by-sentient-life-us

A cosmically interesting troubleshoot.  But I'm not sure about their explanation.  Why would the intermod disappear when they moved the Parkes Radio Telescope off of Proxima Centauri?  


Monday, October 25, 2021

Putting a Ceramic Filter in the "Mate for the Mighty Midget" Receiver


It is really simple.  I had one of the +/- 3kHz (6 kHz wide) 455HT filters on hand.  The spec sheets call for 2000 ohms at both ends, but looking at the schematic it appeared that I already had high impedance on both sides of the filter.  I put a .001 uF cap on the input side to keep the DC voltage off the filter (see above and below). This capacitor allows us to avoid the dreaded problem of electro-migration that is so nicely described by SV8YM here: 


Tasos also provides a good description of the innards of those little black boxes that contain ceramic filters. 

Once you get the filter in your receiver, you have to carefully place the BFO signal in relation to the filter passband.  I have trouble properly sweeping 455 kHz filters -- my HP8640B will not go that low.  Nor will my Antuino (I need to modify the code -- someone help me please).  I know the NanoVNA will do the job, but I just couldn't seem to get it to work.  So I went "old-school" and manually swept the filter using my FeelTech sig gen and my Rigol scope.  This gave me a rough idea of where the passband was.  I put the BFO on the low end of the filter passband, at 451 kHz.

   
With this filter the MMM RX has become a real asset.   The 6 kHz bandwidth allows for nice reception of both SSB signals and AM sigs.   I may try to use one of the +/- 2 kHz filters  (4 KHz wide), but so far I have not been able to find a source for this part. 

Sunday, October 24, 2021

WA9WFA's Mate for the Mighty Midget 1966 QST Receiver

Scott WA9WFA and I have been exchanging e-mails about his Mate for the Mighty Midget receiver project.  This morning I finally took a look at Scott's we page on this effort.  There was a lot there that resonated.  For example: 

"I remember the moment very clearly.  June 1966 I was sitting in a lawn chair reading a stack of QST's that I had brought along to the summer cabin.  The February 1966 issue the Beginner and Novice section introduced the "Mighty Midget Transmitter", a 10 watt crystal controlled transmitter.  The April 1966 issue Beginner and Novice section introduced the "Mate for the Mighty Midget" which was a three tube super-heterodyne Novice type receiver.  Over the course of that summer I read and re-read those articles a jillion times.  Being 13 years old, I didn't have the electrical or mechanical skills to pull off such a project so I could only dream about it.  In 1970 I bought a handful of the parts.  In 1976 I bought more parts.  In 2021 I decided to build it while I still had the ability to do it.  This project is only my second homebrew radio project so I am still learning things every second of the way...
 
While I am not expecting to much in performance, the 13 year old in me is ever hopeful that this 1966 Novice receiver will be the most wonderful radio ever made.   73, Scott WA9WFA"

Scott's MMM RX page: 

Scott and I are now both updating the MMM RX by substituting 455 kHz ceramic filters for Lew McCoy's FT-241 crystal filter.   I have my filter wired in now, and it is working well.  Scott plans on soldering his in today.  I will post on this mod soon. 

On his QRZ.com page, Scott notes the need to fight the temptation to further soup-up this simple receiver:  "I did have to resist the temptation to add another audio stage, a mechanical filter, AGC, 2nd IF amplifer stage, etc..."

Exactly right Scott.  Resist the temptation.   Simplicity is a virtue.  I do use an outboard, powered computer speaker, but I justify this by telling myself that I just don't want to use headphones.  But I could use headphones, so this is OK.  OK?  

Scott's QRZ.com page: 

I must add that I think the yearning of Scott's inner 13 year-old can be fulfilled by the MMM RX.  I think it is pretty wonderful.  It is -- in my view  -- not as good as a Drake 2-B, but it is FAR better than an S-38E, and it is better than a Lafayette HA-600A (wjm).  

Friday, October 22, 2021

Tribal Knowledge: Pete N6QW on "How to Make Things Work"

 
BUILD IT LIKE THIS

Yesterday Pete Juliano published a blog post that contains an enormous amount of tribal knowledge and good advice for homebrewers.   As I read Pete's post, I thought back on my own failed teenage efforts at homebrewing -- the Herring Aid Five fiasco came to mind.  I also thought of Farhan's comments about his similar frustrations with early homebrewing efforts (though I find it hard to believe that Farhan EVER had trouble making something work). 

Above we see a large N6QW prototype breadboard.  Note how it is easy to see where the various stages start and stop.  This is key to understanding and troubleshooting a complex rig.   If you want to see the antithesis of this approach, here it is:

DO NOT BUILD IT LIKE THIS

This was supposed to be an 80 meter DSB transceiver.   The builder (who will remain anonymous) obviously didn't get it to work.  I think he should try again, using Pete's methodical approach. 

Check out Pete's great advice here: 


Thanks Pete! 

Wednesday, October 20, 2021

Super-Regeneration is Super-Strange


Farhan VU2ESE is largely responsible for this.  He has recently been talking about VHF.  (More about this in due course.).  This started me thinking about my failed effort in London to get on 2 meter AM.   My plan was to use the transmit portion of this HW-30 (above) with a 2-to-10 downconverter and my trusty Drake 2-B for receive.  

Tony G4WIF also bears some responsibility:  When I expressed interest in Farhan's VHF work, Tony sent me two articles from SPRAT.  Both of them were about super-regenerative receivers.  

Farhan's comments caused me to pull the HW-30 out of storage.  I started poking around the transmitter.  But then I noticed something:  On receive, the AF amplifier was obviously working.  Then, when I tuned through the 2 meter band, the rest of the receiver seemed to be working too.  I fired up the HP-8640B sig gen on 2 meters and turned on the AM modulation.  Indeed, the old receiver was inhaling!  

This launched me into an effort to understand how super-regenerative receivers work.  There are a lot of really weak explanations out there. You get the distinct impression that the person explaining the circuit does not understand it himself.  This makes explaining it very difficult.  I am not the only one to notice this phenomenon:  Mike WU2D commented on this in one of his excellent super-regen videos.  This one:  


Mike very kindly said the operation of this circuit seems like "magic."  I was thinking more in terms of Voodoo.  

Howard Armstrong discovered super-regeneration years after he invented plain old regeneration.  The new discovery came around 1921.

It looks like VHF guru Frank Jones had very early misgivings about super-regeneration.  In his 1934 classic 5 Meter Radio Telephony, Jones seems unenthusiastic about the circuit and about our ability to understand it:  "To explain, simply, exactly how this form of detection takes place is not a simple matter, but some of its characteristics are easy to visualize."  In this book, Jones goes on to predict that super-regens will be superseded (!) by superhets.  Indeed, in his 1961 book VHF for the Radio Amateur there are no super-regen circuits; all the receive systems are down-converters to HF receivers. 

Still, with that HW-30 hissing away right next to me, I feel I need to understand how the super-regen works.  I'm not there yet, but I'm trying.  Here are some good resources: 

A good article from Wireless World 1946:  

A student's write up of his effort to understand: 

But the best so far (for me) is from Frederick Terman (one of the founders of Silicon Valley) in  his 1943 classic Radio Engineer's Handbook.  Click on the images for a clearer view. 



I will definitely try to get the HW-30's 5 watt AM transmitter going.  I am not so sure I'll do anything with the receiver.  I think this is a matter of picking your battles and "finding joy."   I didn't find joy in FT-8, so I stopped working with it.  Same with my HA-600A, DX-40 Novice rig.  Same with CW in general.  And the same with SDR.  I suspect that super-regen receivers may also fall into this category.  I mean, let's face it, if you are not fond of ordinary regens, is there any real chance that you will like SUPER-regens?  Even Frank Jones seems to have disliked them.  And there is a reason Howard Armstrong moved on to superhets -- they are better! But still, that receiver is hissing away at me...  Stay tuned. 

Tuesday, October 19, 2021

Homebrew Tiny Space Telescopes from the Netherlands


It is good every once in a while to step back from our electronic work benches and take a look at what other kinds of builders are making.   Hack-A-Day led me to this wonderful video from Holland.  There is great background information on telescopes, but the really great part is the interview with the Dutch fellow who is actually making -- in his home workshop -- these tiny telescopes.  Icing on the cake:  One of them will be used in a student Cube-Sat project in Oregon.  

Be sure to stay to the end for an intriguing presentation by Dr. Liam Fullersheit. 

Monday, October 18, 2021

No Longer On the "Shame Shelf" -- Pete Fixes His KWM-1

 

I think a good troubleshoot is almost as satisfying as a successful homebrew.  And we can sense that high level of satisfaction in Pete N6QW's description of his repair of a Collins KWM-1:   


I liked Pete's troubleshoot/repair story, but -- as is often the case -- I struck by his turn of a phrase.  I think Pete has added something important to the SolderSmoke lexicon: 

THE SHAME SHELF 

Most of us have a shelf like this. I have an HW-101 on mine.  Pete shows us that there is hope -- there is path off of the shame shelf.  You just have to know stuff.... Or have IBEW friends like Pete who can advise you. 


Sunday, October 17, 2021

2 Meter Homebrew: The Fredbox (Video)


I predict a rebirth of interest in 2 meter homebrew.  This will probably hit around Christmas time.  The impetus will come out of Hyderabad, India.  At this point, I can say no more. 

I was thinking about all of this today.  I remembered "The Fredbox."  G3XBM's report on this fantastic rig was carried on this blog before it was even a blog.  And the Fredbox goes back much further in time -- back to the mid-1970s.  It must have been great fun to have QSOs with this rig in Cambridge England back in the day.  G3XBM actually crossed the English channel with this 10 mW rig.  FB.  

When I was in London (2003-2007), G3XBM's post on the Fredbox got me interested in 2 Meter AM.  I had a down-converter that let me listen, and I went as far as modifying a Benton Harbor Lunchbox for the proper AM transmit frequency.  I don't think I made any contacts, but I still have the bits and bobs of this rig, so if anyone in the Northern Virginia area wants to get on,  please let me know -- I will blow the dust off this project and will build a 2 meter antenna.  

Here are more details from G3XBM on The Fredbox:  


Hans G0UPL got into the Fredbox in 2009 and 2016: 

Wednesday, October 13, 2021

SolderSmoke Podcast #233: PIMP, Boatanchors, Novices, MMM, Heathkits, DC Receivers, Mailbag


SolderSmoke Podcast #233 is available. 

http://soldersmoke.com/soldersmoke233.mp3

Travelogue: Cape Cod. SST. Marconi Site.

The WFSRA:   The World Friendship Society of Radio Amateurs.


Pete's Bench:

The Pimp.
The NCX rig.
The Collins.
The many DC receivers built worldwide.
The parts shortages are real! Several key radios on hold. Si5351 sub.
Talk to G-QRP convention

Bill's Bench:

FT-8. Not for me. I tried it.
Novice Station Rebuild.
Globe V-10 VFO Deluxe.
Selenium rectifier removal CONTROVERSY?
Not crazy about my Novice station. Not crazy about CW. 
Mate for the Mighty Midget. Again. 
Mike W6MAB -- Detector problems LTSPICE Check
One more mod for MMM RX. Ceramic filter at 455.
Dropped screw inside tubular cap on Millen 61455 transformer. 
Talk to the Vienna Wireless Society
Thinking of a Moxon or a Hex beam.


BOOK REVIEW Chuck Penson WA7ZZE New Heathkit Book. http://wa7zze.com


Mailbag

-- New SPRAT is out! Hooray!
-- Todd K7TFC sent me copy of Shopcraft as Soulcraft. FB.
-- Dean KK4DAS building an EI9GQ 16 W amp. FB.
-- Jack NG2E Getting close on Pete's DC receiver.
-- JF1OZL's website is BACK!
-- Tony K3DY sent link to cool books. 
-- Sheldon VK2XZS thinking of building a phasing receiver.
-- Peter VK2EMU has joined the WFSRA. FB!
-- Ned KH7JJ from Honolulu spotted the Sideband Myth in the AWA video.
-- Chris M0LGX looking at the ET-2, asks about the variometer.
-- Pete Eaton Nov 64 anti HB rant in november 1964 QST. Wow.
-- Josh Lambert Hurley spreading FMLA stickers in the UK. FB
-- Stephen VE6STA getting ready to melt solder.
-- Got a great picture of Rogier PA1ZZ back on Bonaire.
-- Farhan reading the manual of Hans's new digital rig.
-- Paul G0OER wonders if FMLA getting ready to move on 5 meters.

Saturday, October 9, 2021

Recent Homebrew Projects from Jan PA3GSV (of "Mate for the Mighty Midget" Fame)

 

Recent talk of the Mate for the Mighty Midget receiver and Pete's PIMP SSB transmitter brought me back in contact with the work of Jan, PA3GSV.  I took a look at his QRZ.com page and found that he has some projects that rival even his seemingly unbeatable MMM RX project. 

Check it out for some real homebrew eye candy: 

https://www.qrz.com/db/pa3GSV

Friday, October 8, 2021

Bill's 52 year-old Apollo 11 Time Capsule -- What Should I Do?

 
When I was a kid, I was an Apollo 11 fanatic.  I was ten years old when they landed on the moon.  I was convinced that the newspapers and magazines from that event would someday be worth A FORTUNE! So, as a ten year-old, I double or triple wrapped a bunch of them in plastic and put the package up in the attic of my parents' house.  Where they sat undisturbed for more than half a century.  

We were recently getting ready to sell the house, and I asked if my Apollo 11 newspapers were still up in the attic.  They were!  So the time capsule has come back to me after all these years (see above).  It remains unopened.    

Obviously this is not worth the fortune that my ten year-old self thought it would be worth. (Hey, I was 10!)  But it is worth something to me.  I know we have a lot of fellow space geeks reading the blog, so let me ask for advice:  What should I do with this?   

Thursday, October 7, 2021

Another M^3: The Michigan Micro Mote


Move over Michigan Mighty Mite and Mate for the Mighty Midget.   There's a new M^3 in town.  And it is SMALL. 

Hack-A-Day had an article on this today, and while it seems only tenuously connected to ham radio, I found it intriguing.  

Check it out.  Who knows, someday people may be operating in "dust mode":  

Tuesday, October 5, 2021

Dean KK4DAS Builds an EI9GQ 16 Watt RF Amplifier (and Noodles in the Process)

 

I really like Dean's description of the building process, especially where he describes the need to sit down with paper and pencil for some noodling.   We see that in the picture above.  Too often we hear from guys who seem to be looking for detailed, step-by-step instructions, and then get frustrated and stuck when this kind of detail isn't available. Dean shows what to do in this situation:  noodle! 

Check out Dean's blog post on this project: 


Dean's post made me think about the origin of the verb "to noodle."  We know it has its origins in music.  Google provided this interesting explanation: 

To noodle around on something, while it does make use of the noodle (head), may derive from the regional German nudeln, to improvise a song, or from the late-19th-century Scottish sense of noodling as humming a song to oneself. By 1937, to noodle was to fool around with notes to create music.

We noodle around with parts and schematics to create rigs. 

Monday, October 4, 2021

Scott WA9WFA's Mate for the Mighty Midget Receiver is WORKING! (Video)


Wow, Scott got his Mate for the Mighty Midget receiver to work and he is obviously overjoyed with the result.  All of us who have struggled with a homebrew project know just what this feels like.  And it is very cool that Scott got some useful guidance from Charlie Morris in far-off New Zealand.   Congratulations Scott.  I'm really glad you stuck with it.  

Scott's success comes at a good time:  Pete N6QW is building W4IMP's three tube "IMP" SSB transmitter (also from the 1960s).   I accept responsibility for naming Pete's project:  It will be known as "Pete's IMP" or, memorably,  "The PIMP."  For a look at Pete's rig go here: 

Scott had problems getting Lew McCoy's 455 kc crystal filter to work.  So did I.  It turns out that this is a very old problem, going back to World War II.  In Don Stoner's 1959 "New Sideband Handbook" on page 54 he writes of homebrew filters in the 400 to 500 kc range:  

"Inexpensive crystal filters constructed from war surplus FT-241 type low frequency crystals are very popular with the 'do it yourself' hams. These CT cut crystals have been plentiful and relatively cheap for a number of years and are in the hands of many Amateurs. The general run of war surplus crystals may or may not be good. Experience has shown that one out of four of these crystals are usually defective in one way or another." 

Stoner was writing just 14 years after the war.  Add another six decades to the age of these crystals -- often decades spent in musty basements -- and you can imagine the percentage of bad 455 kc FT-241  crystals increasing.  So I think Scott is wise to seek an alternative to McCoy's crystal filter. 

Scott's original build of the MMMRX receiver is just so nice.   In the video he says he plans to go back to it after he gets the expanded version fully functional.  He should definitely do that -- his  original version looks so good.  I think it is probably very close to working properly. 

Thanks Scott, and again, congratulations OM. 

Saturday, October 2, 2021

Selenium RECTIFIED

Selenium rectifiers. The name kind of sounds like Dilithium crystals, possibly related to flux capacitors. 

Anyway, there were two of them in the Globe Electronics V-10 VFO Deluxe that I recently bought.  Obviously they had to go, so I took them out yesterday, replacing them with a 1N5408 silicon rectifier.  

The new diode had a significantly lower voltage drop than the selenium rectifiers -- this pushed the output voltage from the power supply up to around 200V.  It is supposed to be around 185 V.  So I put a 470 ohm,  5 watt resistor (found in the junkbox) in series.   This brought the output voltage to 167 V.  Close enough.  VFO seems to be working fine.  

I'm glad I did the extraction before these aging components released their nasty toxic smoke. 

W3HWJ has a good article on replacing these nasty old parts, with some interesting info on their history:   http://www.w3hwj.com/index_files/RBSelenium2.pdf

Backgound on the element Selenium:  https://en.wikipedia.org/wiki/Selenium



Friday, October 1, 2021

Chuck Penson's Amazing New Book about Heathkit Amateur Products

 

I was very pleased to read that Chuck Penson WA7ZZE was publishing a book about Heathkit's amateur radio products.  His book is a really great guide, providing a lot of fascinating information, stuff that even those of us who have spent decades with pieces of Heath gear didn't know.  For example, I never knew that an after-market dial had been available for the HW-101.   And I didn't know that the Indian names used for many of the Heath rigs (Comanche, Apache, etc.) resulted from a suggestion from Roger Mace's wife, who was Native American. 

Chuck's book arrived just as I was putting my DX-40 novice transmitter back on the air after almost 50 years.  TRGHS.  Who knew that there were TWO versions of the DX-40?  I didn't, but Chuck did, and his book explained how to spot the difference (flashlight through the side vents -- I have the very slightly more modern version). 

When I opened the book for my first peek inside, the page opened to the QF-1 Q multiplier.  I immediately felt guilty about having brutally cannibalized several (well maybe more than several) of these things.  But right there in the text Chuck repeats my justification for the carnage:  He notes that the tuning cap has a nice 14:1 turns ratio.  Exactly.  How could I NOT pull those beautiful variable caps out of that old regen device, for re-use in superhet receivers and BITX transceivers?  

This is a wonderful book that belongs in the workshop libraries of all those who have used and loved Heathkits over the years.   

Order yours here:  


Thanks a lot Chuck for making such a great contribution to the radio art and to ham radio literature. 

Wednesday, September 29, 2021

N2CQR (WN2QHL) Novice Station Re-Created

 
There it is.  The 2021 re-creation of the WN2QHL Novice Amateur Radio Station.  This is what I had when I first went on the air in April 1973 from Congers, NY. 

-- I got my first Lafayette receiver (WITH JEWELED MOVEMENTS!) for Christmas in 1972.  My mom drove all the way into New Jersey to get it for me. 

-- I bought my first DX-40 and the Globe VFO Deluxe from someone in the Crystal Radio Club.

For this re-creation station: 

-- I got this recently acquired Lafayette free-for-pickup from a very kind SWL in the Shenandoah valley.  (I've discussed this receiver extensively here.) 

-- The DX-40 is the result of a couple of junkers that I bought in a hamfest some 23 or 24 years ago.  It might have been the Timonium Hamfest.  I cannabalized one of them and made one good DX-40 out of the two.  Parts of the cannabalized unit carry on the good fight as pieces of my balanced  antenna tuner (the coils were useful there) and as the chassis for my first SSB transmitter. 

-- The Globe VFO Deluxe was harder to recover.  There are just not a lot of these things around.  I actually put up a plea for one of these on the SolderSmoke blog.  Not even the IBEW could come up with one of these things.  But then, last week on Facebook I came across a fellow who was selling one.  Deal!  Check our the nice Juliano Blue light indicating 40 meter operation. 

Putting these three devices together was more challenging than I thought.  To get them to work together decently three different things had to happen as the result of throwing one switch: 

1) Antenna had to switch from receiver to transmitter. 
2) Receiver had to be largely muted (leaving some key-down signal for sidetone).  
3) VFO had to be turned on (I left it running and just keyed the DX-40).  

Fortunately I have almost 50 years more experience than I did when I first set this station up.  So I was able to do this better in 2020 than I did in 1973.   I had a 3PDT relay that I had built for a DX-60 station.  I was able to use it to do all three things described above. 

Muting the Lafayette was a bit tricky.  On the back octal connector they have two post  (1 and 3) that are normally connected.  Disconnecting 1 from 3 completely mutes the receiver by cutting off a needed ground connection to the RF amplifier and to an IF amplifier.  The Lafayette manual tells you to connect these terminals to the "muting voltage" presented by your transmitter.  The DX-40 doesn't have such a voltage, and I was reluctant to connect any voltage to this terminal for fear of blowing up the RF and IF amplifiers.  I figured that just putting a big resistor across 1 and 3 would mostly mute the receiver.  The 3PDT relay shorts this resistor on receive, un-muting the receiver. I use a 500,000 ohm resistor.  It works well, but the sidetone is chirpy while the actual signal is not.  This is a bit annoying. 

I re-capped the DX-40 when I got it back in the late 90's.  Those caps are still good. 

The Globe VFO had also been recapped.  But it still has selenium rectifiers in there.  I will change them ASAP.  Also, the Globe VFO had a somewhat mysterious second transformer in there.  I wondered what that was.  I measured the output:  6.3 V.  That is a filament transformer.  My guess is that the filament winding in the main transformer went open, maybe as a tube failed. Instead of replacing the whole transformer, they just popped in a replacement filament transformer.  That's fine. 

I've been on the air with this rig, mostly on 40, as I was as a Novice.   I can work anyone I hear on 40 meter CW and my CQ's are heard in Europe (as shown by the RBN). 

I'm struck by how physically BIG these pieces of gear are.  Much bigger than our beloved BITXs. 

Regarding T/R switching:   There was a line in the 1973 ARRL Radio Amateurs Handbook that really got to me back in 1973:  Page 640, in the chapter entitled "Assembling A Station:" "

"In any amateur station worthy of the name, it should be necessary to throw no more than one switch to go from the 'receive' to the 'transmit' condition." 

By this standard, my station was probably unworthy of the name.  I don't remember how I handled T/R changeover, VFO keying, receiver muting and sidetone,  but it almost certainly involved throwing more than one switch.  But now, I am happy to report, my novice station is finally up to the ARRL's high standards.  As Pete says, "When you know stuff you can do stuff." 

Tuesday, September 28, 2021

The World Friendship Society of Radio Amateurs

Rod Newkirk, W9BRD wrote the "How's DX?" column of QST magazine from 1947 to 1978.  He had a wonderful writing style.  His column was an inspiration for many of us -- I write about the impact it had on me in my book SolderSmoke -- Global Adventures in Wireless Electronics and here on the SolderSmoke blog

Rod's son David Newkirk is radio wizard himself and has produced many great articles for QST and other publications.  His dad is a Silent Key and David has taken his call.  

This morning I was looking at an article on David's web site in which he looks at some of his dad's old QSL cards.  Most of the affiliations on the cards (ARRL etc.) are easily recognizable, but there was one that was unclear:  WFSRA.  

David figured out what it was: 

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

A W9BRD Affiliation Mystery Solved

My father's pre-World-War-Two QSL cards include the usual list of affiliations: ORS (Official Relay Station), RCC (Rag Chewer's Club), WAC (Worked All Continents), A-1 Op (A-1 Operator's Club). One affiliation, WFSRA, remained mysterious. A clue in the correspondence column in March 1938 QST pointed me to an "I. A. R. U. News" item on page 74 of July 1935 QST, and I had my answer:

W.F.S.R.A.:
    The World Friendship Society of Radio Amateurs has requested publication of the following pledge, which is the sole obligation for membership in the Society:
    "I hereby promise that I will, to the best of my ability, make such use of my amateur radio station as will be conducive to international friendships; that I will never voluntarily permit by station to be used as the tool of selfish nationalistic interests; and that I will do what I can, as a radio amateur and as an individual, to promote world peace and understanding. (To be followed by the signature, address and station call.)"
    Membership in the Society is open to all amateurs in all countries. All that is necessary to become a member is to copy and sign the pledge, and send it to the secretary, Duane Magill, W9DQD, 730 N. 6th St, Grand Junction, Colorado, U.S.A. Copies are preferably to be made in English or French, but may be made in the language of the member."

----------------------------------- 

The WFSRA was apparently one of the many, many peace organizations that were born in the interwar period in response to the carnage of WWI.  In addition to the QST correspondence mentioned by David, Google shows WFSRA in many articles in UK ham and SWL publications, and  there is one mention of it in the May 1954 edition of Boy's Life magazine.    

Much as the CBLA seems to have been presaged by the FMLA, the IBEW seems to have much in common with the WFSRA. 

Monday, September 27, 2021

Lighthouse Larry's GE Sideband Handbook

 

There is lot of information about early SSB and DSB operations in the GE Sideband Handbook (1961).  Lighthouse Larry is very informative.  Early in the book there is a guide to help homebrewers select intermediate frequencies that will work well in SSB and DSB rigs. 

Here is the book.   Remember, we are dealing with tubes and high voltage here: one hand behind your back.  Volts jolt but mills kill!  



Saturday, September 25, 2021

VE7SL's Beautiful Single Tube Transmitter and Single Tube Regen Receiver

Just stunning, in their simplicity and beauty.  Really amazing work.  Kind of reminiscent of my ET-2, but with tubes, and much nicer construction.  More details here: 

RECEIVER: https://qsl.net/ve7sl/neophyte.html

TRANSMITTER: https://qsl.net/ve7sl/neotx.html?fbclid=IwAR3cM6tSRjyTsNouHWVz_buuzz4C9O-IwQbdZM5dekkle69ZW7-JBQcHTVI

Three cheers for Steve VE7SL!  I've been linking to his blog for several years, but somehow I missed this magnificent red rig.   

Steve's online notebook: https://www.qsl.net/ve7sl/

Steve's blog: http://ve7sl.blogspot.com/


Friday, September 24, 2021

Video: N2CQR Talks About Homebrew SSB with The Vienna Wireless Society's Makers Group


It must have been great to have been a ham during the heyday of homebrew gear.  Imagine walking into your local club and finding a dozen or so people who share your passion for melting solder and homebrewing your own equipment.  Well, I got a taste of that thanks to the Vienna Wireless Society's Makers Group.  Led by Dean KK4DAS, this group of intrepid radio amateurs has built versions of Pete Juliano's Simple SSB transceiver.  They are finalizing the rigs; many are already finished.  And I could tell from the questions and the discussion that I was talking to a bunch of guys who knew which end of the soldering iron to grab.  It was really wonderful to talk to people who had gone through the experience of building an SSB transceiver, who knew from personal experience that it is not as easy as it seems. And I could tell from the questions that many of these guys are already thinking of their next projects, of how to put to use the experience they gained building Pete's SSB rig. 

Dean asked me to talk to the group about my recently completed "Mythbuster" rig.  This was a good topic for the group because my rig is similar enough to the Simple SSB that they could relate to it, but different enough that it could give them ideas about how they might do things differently next time. 

I really enjoyed this session.  I'm glad that VWS captured it on video.  I think SolderSmoke listeners and readers will like watching this video.  

Thanks to Dean KK4DAS and the VWS Makers group for hosting me.  And thanks to Jacek KW4EP for helping with the video. 

Here is the Vienna Wireless Society's YouTube Channel: 

Thursday, September 23, 2021

Great News for Homebrewers: JF1OZL's Amazing Web Site is Back!


I was very happy to read this morning (on the G-QRP e-mail list) that the amazingly useful web site of Homebrew Hero Kazuhiro Sunamora has been resurrected after too many years in 404 status. 

Here it is:

https://www.qrp-ja.net/jf1ozl/index.html 

There is a LOT of tribal knowledge and lot of great ideas on his site.  Kazuhiro-san has apparently quit wireless, but is climbing mountains near his home.  We hope is doing well and that he will someday return to radio (perhaps for the peak of cycle 25).  

We last posted about him back in 2011.  In the comments to that post you can see the sad news about the demise of his web site (which is now back on the web): 

http://soldersmoke.blogspot.com/2011/12/homebrew-hero-kazuhiro-sunamura-jf1ozl.html

JF1OZL's bio: 

My name is Kazuhiro Sunamura. I am a 50 year old mechanical engineer, born in 1956. I am not an engineer in electronics. I have been interested in electricity and radio from the age of ten. For the last ten years, I have been active on my ham radio station JF10ZL. I have also written articles about my some of my radio projects in Japanese for the Japanese CQ Magazine. Now I have decided to get onto the internet and will take the opportunity of showing you my equipment and ideas. Please have a look at my schematics. I will be very happy if this material helps you with your own radio projects. I am a member of the J.A.R.L. affiliated Tsuchiura Club, the local ham club in my home town.


Wednesday, September 22, 2021

Some Initial Thoughts on FT-8


 -- This is really interesting technology.  Three cheers for Joe Taylor and colleagues.  This mode would obviously be very useful for fast, weak signal contacts as are needed on meteor scatter or EME. 

-- FT-8 does give you the chance to work DX that would have been difficult on other modes. 

-- Chinese hams showing up on FT-8 -- more than other modes. 

-- I think FT-8 is good for hams who just want to have a lot of "contacts." It is definitely not for the rag-chewer. 

--  I find it it kind of cold and antisocial.  More like a computer game than ham radio. A bit like sending  short text messages on a cell phone. 

--  I think FT-8 contacts are in some ways more meaningless than a "59!" contest exchange -- unless you look, you don't even know the report you got,  nor do you know the report you sent. 

--  For me it is more impersonal than CW.  But at least we let the technology decode the characters instead of having to memorize dot and dash sounds.  In a phone contact you can hear the other person's laugh.  In a CW QSO, you hear him key "HI HI."  FT-8?  No laughter at all. 

-- With PSK Reporter, FT-8 gives you a good feel for how propagation changes during the day. But it is kind of like 2-way WSPR.  As with WSPR, it is -- at first -- fascinating, but then it loses its charm. Yes, everyday you are heard in Belgium. 

-- It seems to be getting kind of crowded.  The passband for FT-8 contacts is often full, and it is hard to find an open space.

-- There is little opportunity for the homebrewer.  I hooked it up to my homebrew transceivers and had a small bit of fun using a 2N3904 as a switch triggered by the RTS signal for T/R.  But that's about it. 

-- I get the sense that the ham himself is not really needed in FT-8.  This mode seems like it could easily be automated or run by an AI.  Just tell it to go out there, make a lot of contacts and log them.  Maybe prioritize the DX you "need."  Has this already been done? 

--  After a session with FT-8, I had a really nice 17 meter ragchew SSB QSO.  That SSB contact left me happy.  The FT-8 session was a bit like spending time on social media or a video game.  It left me edgy.  FT-8 made me appreciate phone even more.

But hey, to each his own.  A lot of people really like FT-8.  I hope they have fun. 

Monday, September 20, 2021

Opening up an Apollo Command Module Microwave Radio System


So much radio goodness in this video.  The enthusiasm of the narrator is unmistakable, and entirely justified. 

A number of things struck me: 

-- Nice shout out to our beloved Parkes Radio Telescope, of  "The Dish" fame. 

-- I like how the French narrator takes some friendly jabs at out use of "archaic British measuring units," and his skillful use of American slang" "Let's open up these bad boys!" 

-- Wow, they filled the radio cases with Nitrogen!  That will definitely save you  money on De-Oxit! 

-- When they opened up the boxes, the construction looked very similar to what I found inside my HP-8640B frequency generator.   

-- Collins built some of this stuff.  

-- 11.6 watts to transmit the TV signal from the moon. 

-- PLL.  

-- A tube type amplifier.  

--- Lots of SMA connectors, but many BNCs also, right? 

-- Finally, and this is really amazing:  THEY HAD A MORSE KEY WITH THEM, JUST IN CASE. 

Thanks a lot to Bob, KD4EBM for sending this to us.  There will be more episodes.  These guys intend to fire up the equipment. 

Sunday, September 19, 2021

Much SSB Tribal Knowledge in Bill Orr's 1959 Handbook

 

There is a lot of really excellent information and tribal knowledge in the 1959 issue of Bill Orr's Radio Handbook.  I was especially taken by Chapter 17 (SSB) and Chapter 28 (Low Power Transmitters and Exciters).  

Looking at the 1959 SSB rigs, I don't see any information that points to the origin of the LSB/USB convention.  Most of these rigs -- especially the phasing rigs -- include provisions for switching to either sideband.  

Check out the "Glove Compartment Sideband Exciter." 


Here is the link to the Orr book: 

http://www.rsp-italy.it/Electronics/Books/_contents/radio/The%20radio%20handbook%2015th%20-%20William%20I%20Orr%20-%201959.pdf

Thanks to Tony K3DY for sending us the link that led us to this book.  There are many other great books there: http://www.rsp-italy.it/Electronics/Books/indexhtm 


Saturday, September 18, 2021

SolderSmoke Goes FT-8 (Briefly, I Think)

 
Idle hands are the devil's workshop my friends.  I was home alone this week, and kind of ran out of things to do.  I started thinking about all those signals on the FT-8 frequencies that I'd hear when the rest of the band was vacant. You know how it is:  One thing leads to another.  I remembered that Rogier  PA1ZZ had sent me some interface boards.  Soon I was downloading WSJTX.  Then I bought a USB-Serial converter from Bezos.  

I hit a major bump in the road when I managed to destroy the little optocoupler that the interface board used for T/R switching.  No big deal though -- Pete has a simpler T/R circuit that worked fine: 


I even made it a bit simpler -- instead of putting an SPDT relay on the Collector of the 2N3904, I just ran a lead to the PTT terminal on my BITX mic input connector.   This terminal just takes one side of the BITX TR relay to ground on transmit.  With Pete's circuit, the RTS signal from the computer causes the 2N3904 to conduct, in effect grounding the BITX T/R relay. Bob is your uncle.  Building this little circuit was fun. 

I used the 600-600 Ohm  AF transformers on Rogier's interface board.  I scrounged up the appropriate connectors and soon I was on 17 meter FT-8.  After about an hour of casual operating (mouse clicking, really) I'd worked HC1HC, HI8CJG, DK4RL, J69DS, F5NBQ, PT2ADM, 8P6ET, KP4JRS, XE2YWH, F4DIA, EA4R, CO3DK, and HI3MRV.    All this while no SSB signals were heard on the band. I was running about 50 watts to my 75 meter doublet tuned to 17. 

The amount of DX you can work is impressive, but I don't know if I'll stick with this mode.  It kind of reminds me of 2-way WSPR.  I find myself wanting to TALK to the DX stations.   FT-8 doesn't let you do that.  But hey, I am not alone in trying out FT-8.  In fact, one of the very first calls that I saw on my screen was the very familiar KB1GMX.  That is Allison, a true radio genius.  That's a good sign.  So maybe I'll have to give FT-8 more of a chance. 

Thursday, September 16, 2021

The HBR-13C Receiver and the Poetic License of Homebrewers

I've been hanging out on 17 meters with my homebrew VXO-controlled BITX transceiver.  The antenna is my 75 meter doublet fed with window line through a homebrew tuner made from dead ( I swear) DX-40s and DX-60s. I can tune it up just fine on 17 meters, but I realize I probably have lots of nulls and lobes in the radiation pattern.  Apparently one of the lobes is over my old stomping grounds in Panama.  Almost everyday I talk to either HP9SAM or HP3SS. 

Robby, HP3SS, is using SDR gear now, but he was a real homebrewer back in the day.  Years ago he built an HBR-13C receiver. That's quite an achievement. 

Robby -- formerly VY2SS -- told me that he sold his HBR-13C to none other than Joe Walsh, the rockstar from The Eagles.  FB. 

As I was talking to Robby yesterday, I came across this wonderful web page about the receiver: 

https://sparcradio.ca/wp-content/uploads/2015/12/Restoring-a-HBR-13-Amateur-Receiver.pdf

Robby told me that his receiver looked almost exactly like the one on the SPARC site, but he didn't recognize the small box with what looked like a speaker on the chassis.  I told him that my guess was that this was a crystal calibrator in an oven. 

I also told Robby that I feel an affinity with the HBR project, not just because I like homebrew superhets, but also because my call in the UK was M0HBR.  

There are some great quotes in the SPARC pdf: 


The SPARC page led me to the amazing website of Kees K5BCQ: 

https://www.qsl.net/k5bcq/HBR/hbr.html

Here is Kees's QRZ page: 

https://www.qsl.net/k5bcq/

Wednesday, September 15, 2021

Drake 2-B Advertisement


A thing of beauty. 

Monday, September 13, 2021

So Where DID the LSB/USB Convention Come From?

-- Bottom line:   I still don't know why ham radio adopted as a convention LSB below 10 MHz and USB above 10 MHz.  There are several theories. but so far there is no convincing explanation in favor of any one of them. And almost all of the people involved are probably Silent Keys by now; this makes it more difficult to gather first-hand information. 

-- I'm not even sure when the convention began to be observed in ham radio. Many of the early SSB books and articles make no mention of it. We don't see it in early ARRL Handbooks. The first mention of it that I found was in the 1965 issue of the ARRL's "Single Sideband for the Radio Amateur" page 8. This article claims that adding a provision for selectable sidebands would "add appreciably to the cost of the equipment. " It went on to say that,  "For this and other reasons there has been a species of standardization on the particular sideband used in the various amateur bands. Nearly all operations in the 3.5 and 7 Mc. phone sub-allocation is on lower sideband, while the upper sideband is used on 14, 21, and 28 Mc."  

-- We know that the informal convention was being followed as early as 1958.  Jim N2EY reports that in 1958, the manual for the Central Electronics 20A shows that LSB was the "sideband most commonly used" on 75, with USB preferred on 20:

-- Some cite a 1959 ITU recommendation on commercial multiplexed radiotelephony as the reason for the convention.  But I don't think this obscure and long-ago ruling explains the convention.  If this were the case, we'd  see follow-up FCC regulation, and at least some discussion of the ITU recommendation in the amateur radio literature.  But we see none of this.  And, as noted above, by 1958 hams were ALREADY -- on their own -- opting to use LSB on 75 and USB on 20.   The 1965 ARRL SSB book refers not to some hard-and-fast rule, but rather to  "a species of standardization" on LSB and SSB.  That ARRL book said nothing of the 1959 ITU recommendation. 

-- There is a widely held belief that this practice originated in the design of a rig that had a 5.2 MHz VFO and a 9 MHz filter.  According to this theory such a rig -- due to sideband inversion -- would produce LSB on 75 meters and USB on 20.  But, as we have demonstrated, this doesn't work, so this theory has to be discounted. 

-- Early SSB activity seems to have been concentrated on 75 meters, and there was a competition for space with AM stations.   SSB operators appear to have used the very upper band edge as their gathering spot.  Using LSB allowed them to operate very close to the upper band edge -- a lot closer than AM stations could go.  This may explain why LSB became the preferred SSB mode on 75.  But how do we explain USB on 20 and above?  That remains a mystery. 

-- It is important to remember that in the early days of SSB, for most hams there were only two important phone bands: 75 meters and 20 meters.  40 meters was CW only until 1952, and even after that was crowded with shortwave broadcast stations.   So a design that allowed for both 75 and 20 was twice as good as a monoband design. 

-- Early on there were designs and parts for phasing rigs.  You could take that ARC-5 VFO at 5 MHz, build a phasing generator around it, and then mix it with a 9 MHz to get on either band.  But with just a simple switch, this kind of rig could operate on USB or LSB on either band.  So the early popularity of this kid of rig does not explain the convention. 

-- There were a lot of surplus 5 MHz ARC-5 VFOs available. There were also FT-243 and FT-241 surplus crystals at both 5 MHz and 9 MHz that could be made into filters.  Later in the 1950s, 9 MHz commercial crystal filters became available.  If you used a 9 MHz filter with a 5 MHz VFO, there would be no sideband inversion in your rig.  If the SSB generator was putting out LSB on 9 MHz, you'd be on LSB on both bands.  So if there was a desire to have LSB on 75, why not just also have LSB on 20? 

-- But if you built a 5.2 MHz filter and a 9 MHz VFO,  you could have LSB on 75 and USB on 20 without having to shift the carrier oscillator frequency.  This would save you the trouble and expense of moving the carrier oscillator/BFO to the other side of the passband.  This desire to economize and simplify may explain why we ended up with LSB on 75 and USB on 20.  But this still begs the question: Why the desire for USB on 20?  

-- Both the manufacturers and the hams wanted there to be sideband standardization.  With monoband rigs, the manufacturers would be able to cut costs by building for only one sideband.  Hams also wanted to cut costs, and they did not want to have to figure out which sideband a station was on when trying to tune him in. 

-- By 1962-1963  Swan and Heathkit were selling mono-band SSB transceivers that used the "conventional" sidebands:  The rigs for 75 and 40 meters were on LSB while the 20 meter rigs were on USB.  There were no provisions for switching to the other sideband. This seems to have reinforced the practice of observing the convention.   (Heath later added sideband switching to the HW monobanders -- in view of the growing observation of the convention, they may have been better off sticking with their original design. Does anyone know why they did this?)  But again, why USB on 20 and above? 

--  In 1963, Swan, by then in Oceanside California, came out with the Swan 240.   Swan used a filter centered at 5174.5 kc. The VFO ran from 8953 kc to 9193 kc on 75 and 20.  The VFO ran from 12222 to 12493 on 40.  This gave the buyer 75 and 40 on LSB, and 20 USB with only one carrier oscillator frequency. (Swan offered a mod that allowed hams to install an additional, switchable carrier oscillator frequency.  I luckily acquired one such modified rig.)  But again, there is an explanation for LSB on 75, but why USB on 20 and above?

This is an important part of ham radio history.   There should be a clear answer.  We need to find it.   If anyone has any good info on this, please let me know.  

Sunday, September 12, 2021

Simple SSB Success in Northern Virginia -- "The Radio Does Not Build Itself...."


Dean KK4DAS and the Vienna Wireless Society (VWS) Builders Group have had some remarkable success with Pete Juliano's Simple SSB design.  Sixteen of the rigs have reached the point where the receivers are fully functional.  Eight more have gone the final (!) stretch and have the full transceivers working.  This week Dean and two other VWS builders met up on 40 meters for the world's first multi-SSSB QSO (see Dean's video in the link below). 

https://kk4das.blogspot.com/2021/09/simplessb-three-way-qso.html

Here's Dean's presentation to the club describing the project and Pete's rig: 

https://docs.google.com/presentation/d/1eUFEO3mZNrwdwaZnyPzr5G6ooozxFoU7/edit?usp=sharing&ouid=100787991139259592659&rtpof=true&sd=true

As Pete says, "The radio does not build itself..."   Indeed it doesn't!  The VWS builders made these rigs.   FB! 


Saturday, September 11, 2021

Visiting the Site of Marconi's Wireless Station at Wellfleet, Massachusetts

 

We were in Boston and the Cape Cod area this week.  We stopped off at the Marconi Wireless site at Wellfleet, Mass.   

This is from the National Park Service web site: 

Spanning the Ocean

For Marconi the ‘great thing’ was to transmit wireless signals across the Atlantic. He built stations at Poldhu, England, Glace Bay, Nova Scotia, and South Wellfleet, Massachusetts. At this stage of wireless technology relatively long electromagnetic waves were used as signals. Transmitting great distances, therefore, required great sensitivity of receivers and tremendous power. Originally, huge rings of masts were installed to support the needed antennas. When storms destroyed them, they were replaced by sets of four wooden towers, 210 feet in height. Power requirements were tremendous. Keroseneburning engines produced 2,200 volts. When fed to a Tesla transformer, the voltage was stepped up to 25,000 volts – the energy needed to transmit longwave signals so far. It was from the Glace Bay station that the first successful two-way transatlantic wireless test message was sent on December 17, 1902.
 
A black and white photo of a man and two women standing in an open area facing a building next to a tall circular array of thin antennas.
The original wireless array.

Impacting Lives

January 18, 1903 the first public two-way wireless communication between Europe and America occurred. With elation, communiques from President Theodore Roosevelt and King Edward VII were translated into international Morse code at the South Wellfleet and English stations, respectively, and were broadcast.

Ocean-going vessels quickly adopted Marconi apparatus to receive news broadcasts, and soon ship-to-shore transmittals were a major operation. Business and social messages could be sent for fifty cents a word. The South Wellfleet station became the lead North American facility for this function. The station’s effectiveness was limited however, so broadcasts were made between 10 pm and 2 am when atmospheric conditions were best.

This brought little enthusiasm from local residents, who endured the sounds of the crashing spark from the great three-foot rotor supplied with 30,000 watts. The sound of the spark could be heard four miles downwind from the station. Eventually, the novelty of wireless telegraphy waned. However, the need for communication at sea remained high. Effective communication resulted in numerous sea rescues, culminating in the Carpathia’s wireless-aided rescue of over 700 people from the Titanic in 1912.

For fifteen years the South Wellfleet sparkgap transmitter continued in commercial use. Skilled telegraphers sent out messages at the rate of 17 words a minute, and station CC (Cape Cod) served in effect as the first “Voice of America.”

https://www.nps.gov/caco/learn/historyculture/marconi.htm






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