First Use of Farhan's Antuino Scalar Network Analyzer

I was learning my way around Farhan's new Antuino this morning.  Very cool.  I decided to start with the Scalar Network Analyzer.   I've spent so much time measuring and plotting filter response curves BY HAND... the Antuino is an opportunity for me to move into the 21st Century.  

In the picture you see the results.  I was using a Heathkit SSB filter with the center frequency at 3.395 Mhz.   The Antuino was set for that freq, with the screen range set at +/- 10.  That means each division on the screen is 1 khz (right?).  The Heath filter is advertised as being 2.1 khz wide at 6 db down.  That pretty much matches what we see here.  

You can see ripple in the filter passband.  This is almost certainly the result of an impedance missmatch.   It looks to me like the Antuino is set up with 50 ohm inputs and outputs.   The Heath filter probably needs higher impedances to have a smooth passband.   I will try later to set it up for a smooth passband. 

It is easy to see how useful this device will be.  Thanks Farhan! 

More on the Antuino here: 

http://www.hfsignals.com/index.php/antuino/

Ham Radio in Germany 1955 (video)

Don't be deterred by the lack of English subtitles -- radio amateurs around the world will be able to follow what is going on in this very interesting 1955 film.  It is only about 14 minutes long. 

This video takes us back to a time when hams were hams and rigs were RIGS!

Note the German OM who apparently slept fully dressed (with necktie) in order to be ready to spring into action on the ham bands in the middle of the night.  That's dedication my friends. 

Also note the fellow sending out QSL cards that feature the schematic diagram of his rig.  Lots of solder melted in 1955.  Great stuff. 

Thank God for the Heaviside Schicht!    

FDIM Interview with Farhan VU2ESE

I didn't realize that our correspondent in Dayton/Xenia had interviewed Farhan.  There was a typo in the audio file name and I was wondering who this UV2ESE guy was.  A Ukrainian QRPer?   I was really pleased to find out that it was Farhan.  

In Bob's interview you will hear Farhan discuss the capabilities of his new Antuino (pictured above).  Pete's Antuino is in the mail, going transcontinental.  It should arrive in the Newbury Park Laboratory later this week.  

As for the spectrum analyzer that Farhan got me last year, I am waiting for retirement (soon!) to get that one going.  But there is a danger that the Antuino will leave little room for the older tech... 

In the interview you will hear Farhan talk about the Antuino circuitry, and about the roots of the three main devices in the Antuino box.  Very cool.  

Thanks again Farhan. And thanks Bob. 

Here is the interview:

http://soldersmoke.com/VU2ESE FDIM 2019.m4a

Farhan's Antuino page: 

http://www.hfsignals.com/index.php/antuino/

FDIM Interview -- NM0S on John Reinartz W1QP K6BJ -- Scandal on an Arctic Expedition?

John Reinartz, 1QP, at the operating position of WNP aboard the Bowdoin

Bob Crane W8SX interviewed Dave Cripe NM0S about his FDIM presenation on radio pioneer John Reinartz 1QP and later K6BJ. Listen to the interview here: 

http://soldersmoke.com/NM0S FDIM 2019.m4a

Here is Reinartz's obit in the New York Times: 

https://www.nytimes.com/1964/10/07/john-l-reinartz-pioneer-in-radio.html

Here is some background info on Reinartz: 

http://k6bj.org/Club_History/WhoWasK6BJ.htm

Dave Cripe's interview left me wondering what the north pole scandal was all about.   I found this passage from a book that seems to partially explain what happened.  Can anyone else shed more light on this unfortunate event?  

Antuino: Farhan's Compact RF Lab In-a-Box

I now have Farhan's latest invention, the Antuino.  Pete will have his shortly.  Very cool.  SWR meter and antenna analyzer, power meter and scalar network analyzer all in one box. I put an old-school knob on the rotary encoder -- it seemed like the right thing to do.  Soon I will be able to find out if my rigs have spurs or are somehow non-compliant.   I'm sure Farhan's "RF Lab in a box" will be an important addition to my test gear arsenal. We will be talking about this in upcoming podcast episodes. 

Mike N2HTT did a nice write up of the new device: 

https://n2htt.radio/2019/05/26/hello-antuino/

And here is the info from the htsigs.com page: 

http://www.hfsignals.com/index.php/antuino/

Thanks Farhan! 

KG7SSB -- Homebrew SSB in Tuscon -- Learning from the BITX40 Module

On Sun, May 26, 2019 at 1:45 PM William R Meara wrote:

Dale: 

  I was talking to Jim W9UD on 20 SSB today.  When I told him I was running a homebrew transceiver he mentioned that he talked to another guy who is on the air with homebrew SSB gear -- you! 

There are so few of us Dale.  I felt compelled to send you an e-mail.  

What are you running?  

After several years on DSB, I started building separate SSB receivers and transmitters, mostly for 17.  Lately I am running versions of the Indian BITX transceiver. 

Please send info on your homebrew SSB projects. 

Thanks,  

Bill N2CQR

Hi Bill, 

I have two radios that are completed to date. I started out building the BITX 40 transceiver from scratch and also a companion 60 watt solid state linear rf amplifier. Then I decided to construct the second transceiver for 20 meter using some of the BITX design concepts and mixed with the UBITX design for additional rf amplification. It too is amplified to about 25 watts output. The 20 meter rig is my favorite radio at this time but I am going to go a different direction on my next build. It's presently just in the design stage but I'm thinking about using the MC1350 integrated circuits for the IF amplification and for the front end I may try using a FET rf amplifier. The beauty of the bitx design is the use of wide band amplifiers that don't have a tendency to oscillate. But, the new design I'm working on will have more shielding between critical circuits and I will use a small amount of negative feedback in the high gain circuits. The reason for changing the radio to a higher impedance design is to simplify the design build. I will basically build a receiver that I can reverse the signal direction over to transmit using the same amplifiers and filters. This will cut in half the amount of circuit building however it will increase the switching circuit complication associated with this new design. 

Today I'm beginning the build of a 100 watt rf linear amplifier design using the kit parts from China (minipa 70) amps. This provides the transformer components and circuit boards. I purchased two kits of parts and I have a large heatsink to build it on. I'm working on a current sensing circuit for protecting the final FETS.  It  will run 4 IRF530's tied together with a splitter and combiner for the input and output matching transformers. It should produce at least 100 watts at 75/80 meters and maybe a little less on 40 meters but 20 meters it will drop off to about 60 or so watts. 

I'm just having as much fun as a guy can have playing around with the homebrew radio's and like you say there's not many doing it these days. I love operating a radio that I built vs. running a factory made radio. I have two commercial rigs on my bench and a couple of Collins radios but the homebrew takes the lead. 

Jim W9UD has become one of my ham friends this year. We end up talking every week or so on the air and keeping touch with local weather conditions.

Side Note:

I wanted to build a SSB radio since I was a young lad with a technician license in the early 60's. SSB came into the picture many years after I was first licensed.  Then move forward to 2015 my ham license had long ago expired during my time in the Vietnam war. I spent several weeks studying the tech, general and finally the extra class exam information and passed on through that adventure. So I decided it's time to build my own radio from scratch. So I started to look online and in books and I still didn't have the confidence to begin building. Then I ran across Farhams BITX 40 and I thought why not buy this radio and just use it as a model of how sideband circuits work. So I did just that and I got it working fine I took the radio and placed it on the test bench and began circuit analysis and signal level evaluation until it all made perfect sense. This is accomplished while transmitting so the levels can be seen on the oscilloscope. Just kill the voltage on the final stage of the bitx. I put a 1khz signal on the mic input. That was just about the only thing I used the bitx 40 rig for and I still keep it handy when I need information. 

Good hearing from you I hope I haven't over done this reply but I really enjoy talking about this subject.

73's Bill.... keep up the building and good luck on your next radio. 

Dale KG7SSB

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

And of course, Pete N6QW knows Dale and has been talking about SSB with him for some time... 

Workshop Tour -- Good use of older test gear (video)

This fellow is making good use of older test gear.  Very nice.  

https://www.youtube.com/watch?v=2LPcLAkhdFE

http://gokarters.com/smf/index.php?topic=2549.0

DIY Waterfall -- A Quick and Easy Panadaptor Using a Sig Gen and O'scope (video)

I've been getting waterfall envy.  The panoramic frequency display is the one thing that could lure me to the dark side (SDR).   Heck, they now have 3D waterfalls!  What next?  Holographic waterfalls? Virtual reality waterfalls?  This is almost too much. 

Anyway, in an effort to counteract all of this waterfall seduction and to show that us analog HDR guys can go panoramic too, I decided to try to create my own panoramic display without resort to SDR.  

Of course, this is a very old technique.  It was invented in the 1930s by Marcel Wallace, F3HM.  He was the inventor of the Panadaptor which was the forerunner of today's waterfall.  Panoramic reception was used by the armed forces during WWII.  In 1946 Hallicrafters marketed a Panadaptor for its ham radio receivers (see below). 

In figuring out how to do this, I thought back to my use of my Feeltech signal generator to scan the response of a crystal filter.  The Feeltech has a very handy sweep feature.  

In this case I set up the Feeltech to sweep from 4.85 MHz to 4.75 MHz in one second.   With the 12 MHz IF of the BITX40 module, this would result in a sweep from 7.150 to 7.250 MHz. 

The sweeping Feeltech just replaced the VFO on my BITX.   I hooked up the Rigol oscilloscope to the audio output of the BITX.  I set the horizontal scan rate at 100 ms per cm.  This would have the trace go across the whole screen in 1.2 seconds. 

After a bit of fiddling, I could see signals on the 40 meter phone band.  But my display would kind of drift along the screen making it hard to know the frequency of the signals I was seeing. 

Alan Wolke W2AEW provided the solution.   He advised me to put a big stable signal at 7.150 MHz near the input of the BITX, then use this strong signal to trigger the 'scope scan.  The HP8640B signal generator that Steve Silverman gave me (and that Dave W2DAB picked up for me in NYC) provided the triggering signal.  

I put a piece of tape across the bottom of the scope display to calibrate the display.  See video above. 

It works!   It is not as cool as the SDR waterfalls, and it does not convey nearly as much information, but it was a fun project. 

More here: https://en.wikipedia.org/wiki/Radio_spectrum_scope

http://www.astrosurf.com/luxorion/qsl-ham-history7.htm

KJ5VW's Cool uBITX Mods (Video)

Beautiful work Gary, and great to see that you are putting ideas from Pete and from Don Cantrell in your rig.  

Gary wrote:

Don and Pete,

I thought you would be interested in the QRP station accessory I added to my version 3 microbitx transceiver.  In addition to using Don's AGC and Reverse/Forward Power and SWR  circuits, I developed another board using a separate Nano and TFT display to show day, date, time, temperature and humidity as well as showing the relative audio strength in three separate bands centered on 400 Hz, 1000 Hz and 2500 Hz.  In addition, when I put the transmitter in a 'tune' mode the power out and SWR will show on the TFT display as well.  The date, time, temperature and humidity information is updated once every minute, the audio is displayed continuously during receive and the power/swr is only displayed when the transmitter is activated.

The audio frequency analyzer is based on the MSGEQ7 microchip and it actually picks up the audio strength in 7 bands covering 63 hz to 16,000 hz.  I just display the three most likely to show up in a SSB transmission.  You can see a 'live' example near the end of the video showing a 20 meter QSO and how the audio strength by audio frequency varies over time.

This project falls into that 'frivolous but fun' category that was a challenge to design but I doubt many other hams would want to replicate it. I learned a lot and wanted to thank both of you for arduino scripts, useful circuits and lots of inspiration for getting started.  I have long admired the work both of you contribute to our hobby.

Here's the link to the YouTube video. 

https://youtu.be/v84TUqsVtTg

73,  Gary KJ5VW

Nigerian Knack: Hope Emmanuel Frank

I hope this kid has a lot of success.  He definitely has The Knack. 

FDIM Interview with KI4IO -- Homebrew Direct Conversion Transceiver

I've been a big fan of Jerry's for several years.  He is the homebrew wizard of Warrenton, Va.  Warrention is just about 25 miles west of us.  Cappuccio the wonder-dog was born on a farm in Warrenton.  

I'm really glad that our ace correspondent Bob Crane W8SX caught up with Jerry at FDIM.  I liked his description of the joy of using a homebrew rig, and of the advantages of direct conversion.   Inspiring stuff!   Listen to the interview here:  

http://soldersmoke.com/KI4IO FDIM 2019.m4a

Be sure to check out the KI4IO page on QRZ.com

Woz on the air -- Age 11

We discussed Steve Wozniak's early involvment in ham radio here: 
https://soldersmoke.blogspot.com/2011/12/wozs-early-exposure-to-electronics.html

Thanks to the K9YA Telegraph for relaying this great picture. 

FDIM Interview with Hans Summers G0UPL on QSX SDR Rig, Probable Price, Features

Wow, our ace correspondent in Dayton/Xenia Ohio, Bob Crane W8SX, did a great interview with homebrew hero Hans Summers G0UPL.  

Hans discusses the success of the QCX CW phasing rig -- more than 7,300 sold.  That's amazing.  I didn't think there were that many solder melters in the world.  

Even more amazing is his description of his QSX SSB SDR rig, which is currently in development.  Click on the link below to listen to Bob's 6 minute interview.  You will be blown away by the features and the price of the QSX.  Go Hans!  

http://soldersmoke.com/G0UPL FDIM 2019.m4a

Thanks Bob! 

Pete sent me his SBE-34

Pete is such a great guy, and such a great ham.  Earlier this week I came home to find a box in the living room.  In it was the SBE-34 that you see in the video.  Pete had been talking about this rig about 18 months ago.  

So many cool features:  The main tuning dial is dual-speed.  There is the "Geneva" band switching method.  Hybrid, with sweep tubes in the final.  All analog.  A power supply that will take 110V AC or 12V DC (internal inverter).   Collins mechanical filter at 455 kc.   Bilateral amplifier stages.  PNP Germanium transistors. 

Pete suggested that I might want to use this rig for parts.  No way!  There is real radio history and amazing innovation in this rig. Plus, it has been worked on by Pete Juliano, N6QW.  

Here is the write up from Pete's YouTube page. Note the part about how they get the BFO signal. 

Here is an example of what an IC7300 might look like some 50 years ago. It is a hybrid rig using Germanium (mostly PNP) transistors in the low level stages. So OK a couple of NPN (2N706) in several key locations such as the VFO. The driver uses a tube similar to a 12BY7 and the finals are a pair of sweep tubes, the 6GB5's. The rig operated on four bands (mostly the then phone portions) 80, 40, 20 and 15 Meters. The power out on 80-20 was 60 Watts PEP and dropped down to 50 Watts on 15 Meters. That was a real stretch. The AGC sucked as you will see in the movie and the receiver gain was a compromise --too much on the low bands and weak on the higher. This was a bilateral design -- which predates the Bitx series by some 40 years--but not the 1st.The first bilateral design was the Cosmophone - Google that one. The major selling point --a Collins mechanical filter. Also an innovation was how LSB / USB was achieved using a single crystal. It was pure magic and innovation. The basic BFO frequency of 456.38 was doubled and then doubled and tripled again. The first 2X gave you 912.76 KHz and the 2nd 2X gave you1825.52 KHz and a tripling gave you 2738.28 KHz. Mixing that back with 456.38KHz gave you 2281.9 KHz USB or LSB. The VFO operated in the 5.5 MHz range and there were heterodyne crystals to put you on the proper bands. Now that was some clever math! You can download the maintenance manual at BAMA manuals. There were some smart guys leading our ham radio efforts back in the day.

Stop what you are doing! Go to the Radio Garden!

This is really fantastic.  The screen display is like Google Earth, but all the green dots are local broadcast radio stations.  Put your cursor on the dot and listen to that radio station live.  And it works very well.  If there are several stations in the same town, just zoom in.  

In the course of a few minutes this morning I was listening to stations in Guatemala, Costa Rica, Getxo Spain, and Bengaluru India.  

Go to the radio garden: 

https://radio.garden/

Another Amazing SSB Rig: VK3HN's "Summit Prowler 6"

Here is another truly amazing compact SSB rig.   Paul Taylor VK3HN is a true homebrew wizard.  So many great homebrew rigs come out of Australia.   

More details: 

https://vk3hn.wordpress.com/2019/05/01/summit-prowler-6-a-pocket-sized-ssb-cw-transceiver-for-80-40-30-and-20m/

Paul's QRZ.com page: 

https://www.qrz.com/db/vk3hn

Peter DK7IH's Amazing Rigs and Blog

It has been a few years since we last mentioned Peter DK7IH.  He has continued to melt solder and to document his work on an excellent blog: https://radiotransmitter.wordpress.com/

I was especially interested in the rig pictured above.  NOTE:  NO GLOWING NUMERALS.  That rig has an analog VFO.  The blog article provides some great pointers on how to achieve thermal stability.  Also, be sure to check out his "Old School" rig.  

I've put Peter's blog in the blog listing on the right side of the SolderSmoke blog.   

Book Review: "Man of High Fidelity: Edwin Howard Armstrong" (Free Download)

Dave W2DAB sent me this wonderful book.  He picked up a copy at a recent Columbia University lecture on E. Howard Armstrong.  Written by the notable science writer Lawrence Lessing, the book was first published in 1956.  The paperback copy that Dave sent me came out in 1969; while 50 years old, my copy is in remarkably good shape. 

I really liked the book.  The author captures the technical achievements of  Armstrong, while also describing vividly the world in which Armstrong lived.  Being from the area, I especially liked Lessing's description of New York City and the Hudson Valley in the early years of the 20th century. This was the world of my grandparents; Lessing's book helped me understand it better. 

For the radio amateur, I think the most gripping part of the book is the way Lessing describes  the excitement of early radio.  Armstrong was a true enthusiast for the new technology, and he was -- even as a teenager -- at the cutting edge.  He was constantly striving to improve the technology, especially the receivers.  Like us, he often became obsessed with his radio work, often forgoing sleep and missing family meals as he toiled away in his workshop. Lessing tells us of Armstrong's astonishment and joy, when, upon inventing the regenerative receiver, he was suddenly able to clearly receive signals from distant stations that previously had been barely discernible.  Realize that when he was doing that, he was the only person on the planet who was doing it.  He was the inventor. He was the first. 

Lessing gives us a lot of great information about Armstrong's work as an officer in the U.S. Army Signal Corps in Paris during World War I.  We learn more about how his desire to be able to detect noise from the electrical systems of enemy airplanes led him to the invention of our beloved superhet receivers.   But my favorite Armstrong in WWI story involves his visit to the radio shack of the ship that was carrying him to the war.   In the radio shack he found a conventional station.  But he asked the operator if he happened to have one of the then new audion tubes.  On the spot, Armstrong took the tube and rigged up a regenerative receiver.  He and the ship's radioman then delighted in hearing stations that had never before been audible.   Amazing.     

I was less interested in the sad tale of Armstrong's legal patent battles, so I kind of skimmed through that.  I'm also not much of an FM guy, so I'll save those portions of the book for a later date.  

I think this is an important book about a significant part of radio history.  It is well written.  It gets almost all of the technical details right (but sorry Mr. Lessing,  radio waves are not composed of electrons).  The book deserves a place on the shelf of all radio history libraries.   If you can't get a print copy, an online version can be downloaded here: 

 https://archive.org/details/in.ernet.dli.2015.189098

Thanks again to Dave W2DAB.   

"Want one!" F6DMQ's Remote Rig

I talked to Yves F6DMQ last night on 20 meters.  I was on my all-analog BITX20.   Yves was up in Toulouse, operating his station near Cannes via this EXTREMELY COOL remote rig.   He connects to the home station via 4G.   Check out the rest of his station here: 

https://www.qrz.com/db/F6DMQ

The Echophone EC-1 -- Chicks Dig it! In the Middle East! With a Hookah!

We've covered the success of this fellow before:  
https://soldersmoke.blogspot.com/2017/09/hallicrafters-and-romantic-life-of.html

But never before with a hookah!