Hack-a-Day: Has DIY become Click-and-Buy?

https://hackaday.com/2021/12/11/has-diy-become-click-and-buy/

Hack-A-Day today asks about the boundaries between DIY construction and the use of purchased, completed electronic components.   This is closely related to our long-standing discussion of what really constitutes "homebrew." 

Is it really homebrew if you buy a bunch of  already-stuffed PC boards and connect them together?  

Is it really a homebrew receiver if 90% of the components are inside one chip? 

Is it really homebrew if most of the signal processing is done in your computer (that you definitely did not build)? 

The comments below the article are interesting.  There we see some of the same arguments used by ham radio operators who are more inclined toward click-and-buy. They argue that since none of us are making our own resistors and transistors, we are ALL therefore click-and-buy people, so we should just get over it and pull out the credit cards. Some commenters carry this to extremes and ask if the real homebrewers are out there mining the copper for their wires.  

The debate seems to spill over into the software area:  One person asks if it is really DIY if you are using software libraries that contain code written by someone else.  Or to be truly DIY should you write all of your own code in assembly language?    

There is one very insightful comment about hams who are inclined to disparage the homebrewing that they did in their youth.  We often hear this:  "Oh, I used to build my own gear, but now-a-days I just buy commercial transceivers -- they are so much better."  As if homebrewing was a folly of youth, something that they grew out of (and up from) as they became able to afford the latest ham radio appliances.  As if homebreweing were a regrettable thing that was done only out of necessity.   This is, I think, sad.  

I think I'm a lot closer to the traditional concept of DIY than I am to click-and-buy.  I still prefer LC oscillators to Si5351/Arduino combos.  I prefer traditional filter rigs to SDR rigs.  And I prefer to make my own crystal filters.  I don't like to use ICs unless I really understand what is going on inside them (so I can be comfortable with an NE602 or an LM386, but I'm not comfortable with a CPU chip that may have millions of transistors in it).  But I am not homebrewing my own transistors nor am I mining copper. 

What do you folks think about this? 

https://hackaday.com/2021/12/11/has-diy-become-click-and-buy/

Farhan's Amazing Knack Story: From a Boyhood SW Receiver to the Design of the sBITX SDR

The presentation starts at about the 4 minute point. 

I think if I were only allowed to watch one YouTube video in the next year, I'd make it this one. 

In this amazing RSGB video, Ashhar Farhan VU2ESE takes us back to his earliest days as a radio amateur.  He tells us about his very early desire to build radios, his early projects, and his personal evolution as a designer and builder,  from a simple DC receiver, to the BITX, the Minima, the uBITX and now the hybrid HDR/SDR sBITX.  

There is a lot of  homebrew wisdom and tribal knowledge in this video. And we learn so many hitherto unknown details about the rigs that have become so important to us:  

-- Farhan had the EMRFD book with him on the famous flight from Sweden to India during which the BITX was designed. 

-- We learn about the origins of the BITX oscillator circuits, and that the VFO and BFO are essentially the same.  

-- I was really pleased that Farhan included a picture of my HB BITX17 rig in his presentation. 

-- Farhan discusses the difficulties he faced in obtaining needed parts in India. 

-- We actually see the nylon washers that Farhan used in the original BITX. 

-- Farhan discusses his early system for measuring coil inductance. 

-- In addition the huge contribution of EMRFD,  Farhan talks about how he was helped by Pat Hawker G3VA's writing, and the ARRL's SSB Handbook. 

-- Farhkan talks about his Tex 465 'scope and his building of a Spectrum Analyzer. 

-- We see his evolution to dual conversion. We see the conceptual birth of the Minima and the birth (thanks Wes!) of the TIA amps.  I didn't know about the HF-1.  Then Farhan designed the uBITX and now the sBITX.  

 -- Farhan talks about his practice of taking the pictures of new rigs with the new rig sitting atop the book that was most important in its design and construction.  FB. 

-- I was really blown away by Farhan's presentation of how the uBITX advertisement was inspired by and in many ways based on the Heathkit ad for an HW-101.  Amazing. 

-- I learned a lot from Farhan's discussion of SDR theory.  I pledge to spend more time with this.  I really like Farhan's hybrid HDR/SDR approach. 

-- But I have a question:  Farhan seems to say that we'd need a big expensive GOOGL computer to do the direct sampling HF SDR.  But doesn't the little RTL-SDR do just that?  Without a GOOGL?  

-- Great to see Wes's AFTIA being used in the sBITX.  

-- Really cool that Farhan has his mind on VHF transverters when designing the sBITX.   I liked use of the TCXO module to free up one of the Si5351 clock outputs.   FB.  And great to include an idea from Hans in this rig. 

Thanks very much to Farhan (who stayed up until 3 am to do this!) and to the RSGB for hosting.

Mythbuster Video #15 The Mythbuster Signal As Seen in the NA5B WebSDR

Mehmet NA5B has an excellent WedSDR receiver in Washington D.C., about 9 miles east of me. I often use it to check my signal quality. I think this video shows that the 10 pole crystal filter is working and is producing a signal with very sharp drop-off outside the 2.7 kHz passband. You should focus your attention to the passband (yellow vertical lines) near 3895 kHz. That's me.

Once, when I was describing my 40 meter DIGI-TIA to an SDR guy, he seemed surprised that I was using a -- gasp -- crystal filter. "Your skirts must be atrocious!" he said. My HDR sensibilities were deeply offended.

I had hoped that the 10 pole crystal filter would produce skirts so nearly vertical as to make my signal indistinguishable (in the waterfalls) from the SDR signals. At least at this low signal level, it appears to be working.

Farhan and the SBITX on Hack-A-Day

 https://hackaday.com/2021/08/06/sbitx-hackable-hf-sdr-for-the-raspberry-pi/

Video: Rob Sherwood NC0B on Transceiver (and Especially Transmitter) Performance

 Rob Sherwood NC0B is one of the real authorities on receiver performance.  Many of us have relied on his ratings of commercial receivers for many years.  His recent presentation to the Madison DX Club has a lot of really interesting information. There is also, I think, some stuff that homebrewers will find distressing. 

Just some things that I noticed: 

-- Rob mentioned a move back to 9 MHz IF filters and a move away from dual-conversion rigs with a high IF.  He also mentioned the combination of a 9 MHz IF and a 5 MHz VFO as a way of easily getting on both 75 and 20 meters.  

-- Rob discussed phase noise from synthesizers, a topic we discussed at length (some would say ad nauseum!) a year or so ago. 

-- Rob really praised the "Pure Signal" system of one of the SDR manufacturers.  He showed the completely rectangular waterfall display of a Pure Signal transmitter.  I'm afraid that simple crystal rigs might never live up to this standard.  An embrace of this high standard could discourage the construction of simpler, HDR rigs.  We should not let the perfect be the enemy of the good!  

-- We often hear SSB ops complaining that some other SSB op is "splattering all over the band."  It often turns out that what is really happening is that a clean SSB signal is just overloading the receiver of an operator who does not know how to turn off his pre-amp or turn on an attenuator.  Rob shows us how to really know if the problem is in fact at the other end:  He looks at key clicks from two different CW signals on 160 meters.  Both are at roughly the same level in his receiver  But one is clicking all over the place while the other is not.  With this kind of comparative info, we can be sure that the problem is the transmitting station's fault. 

-- In discussing when to turn on the pre-amp (or the attenuator) Rob revives the old practice of just listening to the band noise. If you can hear the band noise when you switch from dummy load to receive antenna, you have enough RF gain.  Adding more will only make things worse. 

-- There was an interesting question about how to evaluate the performance of receivers when there are many signals inside the receiver's passband.  This is the case with FT-8.  Rob said this situation needs more research. 

I don't mean to be critical here -- Rob is the guy who evaluated commercial rigs.  And he is a contester.  So his presentation is, of necessity, going to have a very "appliance operator" orientation.  There seems to be an assumption that the only "rigs" that modern hams can use are commercial products. At one point Rob admits that most hams just can't repair these rigs. There is much for homebrewers to learn from experts like Rob, but presentations like this also remind us of what a tiny minority we really are, and how most hams have moved completely away from the old ham tradition of building our own rigs.  

Thanks to Rob Sherwood and the Madison DX Club.  And thanks to EI7GL for alerting us to this important presentation. 

Farhan's sBITX -- Combining SDR with the Traditional Superhet

Here is Farhan's amazing presentation to the virtual 2021 FDIM event.  There is a lot of tribal knowledge in this video.  Lots of old and new technology.  I was especially intrigued by Chris Trask's Kiss mixer.  Farhan's discussion of simple Arduino-based speech equalization and compression made me think that I have work to do in this area. And of course, Farhan's whole discussion of how to bring SDR into -- literally into -- the circuitry of a uBITX is really cool and very educational.   

SolderSmoke Podcast #230 is available! Apr 1, Mars, Group Build, SDR, SSB, Mich Mighty Mites, Mailbag

SolderSmoke Podcast #230 is available for download

http://soldersmoke.com/soldersmoke230.mp3

N2CQR was down for maintenance 

A few words about April 1

The Ingenuity helicopter

China lands on Mars

Brood X Cicadas arriving in NOVA 

Pete's Bench

The Dentron Project

The Spillsbury Tindall SBX-11A

KK4DAS and the Simple SSB Group Build

TenTec mods

Shack Mystery solved.  Maybe 

Changing the channels at age 9 

Bill's Bench

Why LSB below 10 MHz? The "SSB Legend" Rig

WU2D RTL-Dongle Up converter

Understanding the Gilbert (Jones) Cell

SDRSmart  RTL-SDR.com V3 Dongle 

VK3HN and 2 meter SSB

Jack NG2E, MMM and the 10 minute transmitter

KD4EBM sends me SST by Wayne Burdick. DX!  

A new computer 

Mailbag: 

MM0ACN

VK2EMU

N5VZH

VE3KZJ

HS0ZLQ

AD0JJ

VK8MC

KK0S

VE3VVH

KB3SII

WA9WFA

M0NTV

W2DAB

 60 Minutes Story on Mars Ingenuity Helicopter: 

https://www.cbsnews.com/news/nasa-drone-mars-60-minutes-2021-05-09/

A Satellite Ground Station (Receiver) Made from Junk

Very cool.  This guy (who brew up on an island in Alaska) really knows how to use aluminum tape and the junk that fills most workshops. I like his use of the security camera mount as an az-el antenna rotator. 

I foolishly discarded a Direct TV dish.  I could have been receiving GOES images by now! 

Just last week I got the same RTL-SDR.com V3 dongle that he is using.  Very FB.   It does HF direct sampling with no hardware mods and no upconverter. 

More from the builder, Gabe Emerson (KL1FI): 

https://www.youtube.com/channel/UCNLRcEn78Vc62C3GkMvBgtA

http://www.saveitforparts.com/

"Analog Man in a Digital World" by OM Joe Walsh (music video)

After seeing my last post about SDR, the dongle, the Android tablet, and the Bluetooth mouse, Bob Keller grew concerned about my, uh, stability.  Here is our e-mail exchange. 

Bill, 

Have you had a comprehensive medical evaluation recently? All this digital activity from an erstwhile analog man is a concerning symptom. <g>

I suggest listening to the following number at least once each day until you have the chance to get checked out:

https://youtu.be/6YkAnv8inQE

-- 73 de KY3R, 

    Bob Keller

Bob: 

I know.  It really is quite disturbing.  I've been getting a lot of "welcome to the dark side" messages!!!  

I am now trying to get back in the good graces of The Radio Gods.   Today I fired up the Fish Soup 10 and made two CW SKCC contacts on 40 meters.  I feel better already.  

Thanks for the song from OM Walsh.  I had heard it before but it is more meaningful to me now.  I will put it on the blog.  Others may need help too.  

Thanks for caring Bob.  

73  

Bill 

My Hodgepodged Morse: Audio Tone into the Mic Jack Creates J2A not A1A. BASTA!

In SolderSmoke podcast #229 Pete and I were discussing my rather flaky effort to turn the Hodgepodge BITX40 Module into a CW rig by injecting keyed 700 Hz audio into the mic jack (see video below). We got some very helpful responses from ND6T and VK2EMU:  

Hi Bill,

You mentioned generating CW by modulating SSB: Collins did that in their

first SSB transceivers, I believe, as did SGC, but the results were less

than optimal. The problem is that you are involving the audio chain and

modulator. You know from experience how difficult it is to maintain low

intermod there and the tone is no exception. So we end up with lots of

spurs within the filter passband and then also have the opposite

sideband suppression less than perfect. If you check your transmitted

signal with a spectrum analyzer or SDR you can easily see the nasties.

Listening to a CW signal thus generated makes it obvious unless it is

buried way down in the noise. It IS a valid CW signal (not MCW) since it

is (almost) a single signal. However, in actual operation it doesn't

work very well.

I know because I have done that. I bought one of Farhan's original

BITX40 boards and wanted to put it on CW. I ended up injecting a keyed

signal from one of the spare clocks on the Si5351 into the RF amplifier

chain (thus avoiding the above stated problems) but still had garbage

from the audio and IF stages. I fixed that by shorting out that signal

during transmit by a transistor to ground. That was documented on your

BITXhacks website: http://bitxhacks.blogspot.com/2017/02/ and on my

website: http://www.nd6t.com/bitx/CW.htm . It has been a while, eh?

...

Don, ND6T

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

Hi Bill and Pete,

With putting an audio oscillator into you hodgepodge radio, your transmission is not the same as a standard CW rig.

If we have a transmitter as described in the ARRL handbooks from the 1940's or 1950's, (or even the Michigan Mighty Mite) it is a crystal oscillator and maybe a PA tube. By keying either the oscillator and/or the final PA on and off, then we can send Morse code as ICW Interrupted Continues Wave. If we check the list of emission designators, we have A1A.

However, if we feed a tone into a SSB transmitter, then we have J2A.

At the other end it may sound the same, but because it is created in a different way, it has a different designation. 

A quick look at Part 97 shows that J2A and J2B are classed as CW, so you are in the clear. However, if you put a tone oscillator into an AM signal to send CW, then that would be classed as A2A and not classed as CW, but as MCW. MCW can be used on 6 meters and above, but not HF.

SITS.

73 de Peter VK2EMU

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

So I say BASTA with the J2A!  If I want to go CW, it's all A1A for me.  I dusted off my Fish Soup 10 and am now back on 40 CW with 200 mW.... A1A all the way! 

 

SolderSmoke Podcast #229 -- G2NJ Trophy, SDR, HDR, CW! Mailbag

Soldersmoke Podcast #229 is available: 

http://soldersmoke.com/soldersmoke229.mp3

--  G2NJ Trophy is awarded to Pete Juliano, N6QW. 

 -- Get your vaccine shot as soon as you can!  

-- More from "Conquering the Electron" by Derek Cheung. 

-- Bad fire in the chip factory.  Such a shame.  Sad!  I had NOTHING to do with it.  I was home that day.  I can prove it.

 -- Bezos is not such a bad guy.  Turns out he is a space-geek.  

 -- Perseverance was the big space news.  Very cool.  

 

Pete's bench:

Raspberry Pi vs. Microcontrollers

Treedix display

Conversion of the Dentron Scout

CW rigs?

6L6 on a wooden chassis

SHAMELESS COMMERCE DIVISION-  

I NEED TO BUILD UP TIME VIEWERS VIEW MY VIDEOS: So please watch!

https://www.youtube.com/channel/UC20TcdWSSFliMhg3k2A1a5w

--  Our Patreon sponsors get an early look at our YouTube content.  So please, consider

becoming a Patreon sponsor.

--  Please continue to use the Amazon search engine on the blog page (upper right).   

Bill's bench: 

Hodgepodge:   

-- BITX40 Module.  

-- Ramseykit Amp. 

-- San Jian counter,  

-- CW using 750 Hz oscillator. 

-- RF-actuated piezo buzzer.  

-- SDR!  SDR using PC and tablet.  

-- Checking the output with SDR.  

-- Moving the carrier osc frequency.  

 Also, I put the Fish Soup 10 back on the air.  Nice contacts under 200 mw.

Up next:  A rig for 80/75 and 20 meters.  Single Conversion.  Using VFO from a Yaesu FT101 that runs 8.7 – 9.2 Mhz.   Quiz question:  What IF should I use?

MAILBAG

Mark Zelesky sent me wood tokens with power and Ohm's law formulae.  Thanks!

Scott WA9WFA Built a really nice Mate for Mighty Midget RX – getting it going!

Tryg EI7CLB found board of his George Dobbs Ladybird RX.  Rebuild it OM!

Tom WX2J – We talked about “No lids, no kids, no space cadets” nastiness.

Nick M0NTV about sideband inversion.  I like the simple rule about subtraction.

Jonathan M0JGH – Always listen to Pete.  Got married, has mixing product. Leo?

Mike AE0IH.  Dad used a BC-348 in the service. Looking for one.  FB.

Adam N0ZIB – “Silent Shep” site --- with some ham radio shows I had not seen.

Walter KA4KXX in Orlando has a similar subtraction problem with San Jian counter.

Bill N5ALO sent me a really nice KLH speaker.   I’m using it now.

Jason N2NLY – interested in building SSB transceiver.  One step at a time OM…

Trevor in Annapolis sent xcsd cartoon that really hit home. 

Farhan is doing OK in India, diligently protecting his family from the virus.  

Peter VK2EMU also doing well.

Dave AA7EE Casually killed a DC receiver in Hollywood, and disposed of the remains. 

Charlie ZL2CTM doing great things with simple SSB.  Blogpost.

Phil VK8MC in Darwin sends article on "Mend not End" battle against planned obsolescence.

Bob KY3R re my SDR adventures, asked if I’ve had a recent medical/psychiatric evaluation. 

Hodgepodge: Tablet SDR with a Bluetooth Mouse (video)

I continue to find things in the shack that I can connect to the Hodgepodge.  Here it's an old Android tablet with a Bluetooth mouse.   

The waterfall is pretty, but this addition just shows why SDR is really TOO easy.  The modified RTL-SDR dongle is doing direct sampling, so there is not even any phasing circuitry to tinker with.  All the filtering and sideband selection is happening in software inside the 40 buck Android tablet.  The results look nice, but I don't find it very satisfying -- all I did was connect some cables.  So it's back to HDR for me. 

Hodgepodge: Moving the Carrier Oscillator Frequency (and a Flashback to 2002) (Video)

As explained in the video, in the course of using my RTL-SDR dongle I noticed that the signal being put out by my Hodgepodge rig had some problems.  There was poor opposite sideband rejection, and in terms of audio quality I has putting out too many lows and too few highs.  I figured the problem was the result of the carrier oscillator frequency being a bit too low, a bit too close to the flat portion of the crystal filter passband.   I needed to move that carrier oscillator frequency up a bit. 

BITX40 Module BFO 

In the actual BITX40 Modules, L5 was replaced by just a jumper wire, and the C103 trimmer was not on the board.  Farhan and his team instead selected X5 crystals to match the passband of the 12 MHz crystal filter. Mine was originally at 11.998653 MHz.  But I wanted to tweak mine a bit -- I wanted to move it up about 500 Hz.  Reducing the capacitance would move the frequency up. Putting capacitance in series with C102 would have the effect of reducing the capacitance in the circuit.  I just removed the jumper wire and used the holes for L5.  First I put in a single 30pf capacitor.  This dropped the capacitance between X5 and ground to 18 pf.  That resulted in too large a shift.  So I added another 30 pf cap in parallel with the first one.  This resulted in a total capacitance from X5 to ground of 26 pf.  This was about right -- the carrier oscillator/BFO frequency was now 11.9991 Mhz.  I had moved the carrier oscillator frequency up by 447 Hz -- just about what I was hoping for.  

This was a very satisfying fix.  it was a chance to put to use experience with other SSB rigs, to make use of the RTL-SDR dongle as a diagnostic tool, and to tinker with the BITX40 Module in the way that Farhan had intended for it to be tinkered with.  

I'd done this kind of adjustment before, but without the benefit of an SDR display.  Below is the story of one such adjustment. 

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

A Flashback to 2001-2002

(From my book "SolderSmoke -- Global Adventures in Wireless Electronics")

Now it was time for some debugging and fine tuning.  I needed to make sure that the frequency of the carrier oscillator was in the right spot relative to the passband of the crystal filter.  If it was set too high, the filter would be chopping off high notes in my voice that were needed for communications clarity, and it would allow too much of what remained of the carrier (residuals from the balance modulator) through. If it was set too low, the voice signal transmitted would be lacking needed base notes.  I didn’t have the test gear needed to perform this adjustment properly, but my friend Rolf, SM4FQW, up in Sweden came to my aid.

One night, during a conversation with Rolf, I explained my problem and he offered to help me make the adjustments… by ear.  Performing an electronic version of open-heart surgery, with power on and Rolf on frequency, I opened the case of the new transmitter.  The carrier oscillator has a small capacitor that allows the frequency of the crystal to be moved slightly.  With Rolf listening carefully, I would take my screwdriver and give that little capacitor a quarter turn to the right.  “Better or worse?” I would ask. 

I think this little adjustment session captures much of the allure of ham radio.  There I was, out in the North Atlantic, late at night hunched over a transmitter that had been forged from old Swans and Heathkits, from cell phone chips, and from bits of design from distant members of the fraternity of solder smoke.  Pericles, the source of many of the key parts, was gone.  So was Frank Lee, the amateur whose SPRAT article had inspired the project.  But Rolf and I carried on with the core tradition of the radio fraternity: hams help their fellow hams overcome technical difficulties.  

EXORCISM! 40 Meter RFI Problem Resolved

BEFORE

David W. suggested I use my RTL-SDR dongle to look for the source of the 40 meter RFI that I have been mentioning.  (It appears as an ugly stipe in the waterfall of my Hodgepodge transceiver.) So I fired up the RTL-SDR -- there were the tell-tale spikes, spaced neatly every 50 kHz.  The ARRL Handbook says this is typical of a switched power supply.  Before I started patrolling the neighborhood with a tin-foil hat and a portable receiver, I decided to check my own house for any recently installed electronic devices.  It didn't take long -- when I unplugged the new (mid-pandemic) treadmill the spikes disappeared.  This treadmill was located about ten feet above my rigs, and between the rigs and the antenna.  Duh.  I should have thought of this earlier. Mystery solved.  Thanks David. 

AFTER

Over the Waterfall into the Dark Side: Hodgepodge SDR

This one's for Pete. My effort to add features and modes to my Hodgepodge transceiver took a dramatic turn when I connected the rig to my computer via an RTL-SDR dongle. Woohoo! A Hodgepodge waterfall! Check it out.

The dongle was modified for direct sampling at HF. In the box with the dongle I have one amplifier stage, consisting of a 40673 dual gate MOSFET and one parallel tuned circuit, now tuned to the Hodgepodge IF of 11.998 MHz. I tap the the Hodgepodge's BITX40Module at the output of the first mixer, just before the crystal filter. This was a lot of fun. I can even check my own signal on transmit! This is like having the best of both worlds.

A Step Closer to the Elser-Mathes Cup? Ham Receives Signals from Mars

 

That is the antenna that Scott Tilley VE7TIL  used to receive signals from the Chinese spacecraft Tianwen-1 in orbit of Mars.  In a recent SpaceWeather article, Scott comments on the importance of SDR receivers in these deep space reception efforts.  

https://spaceweatherarchive.com/2021/02/16/ham-radio-signals-from-mars/

I've been watching the Elser-Mathes cup for a long time. I dedicated my book "SolderSmoke  -- Global Adventures in Wireless Electronics" to my kids, Billy and Maria, noting that they were both possible future winners of this most prestigious award.  Scott Tilley's work has put us a step closer to an award ceremony for some intrepid radio amateur. 

Here is a good article on the Elser-Mathes Cup: 

http://www.arrl.org/files/file/QST/This%20Month%20in%20QST/June2016/Schoenfeld.pdf

Scott was in the news last year for finding a zombie satellite: 

https://soldersmoke.blogspot.com/2020/04/quarantine-search-for-zombie-satellite.html

A Quantum Mechanics-based Receiver. The Rydberg Detector

 

Looks like you SDR guys are going to have to up your game!  

https://phys.org/news/2021-02-quantum-entire-radio-frequency-spectrum.html?fbclid=IwAR1nZZikA9VwMYbVCSMfeoJs7cj6XVKWa49LPCQ1LfWOON-iN62LvU6k2WM

SolderSmoke Podcast #228

Soldersmoke Podcast #228 is available: 

http://soldersmoke.com/soldersmoke228.mp3

Of course, no travel.  But vaccines are here so maybe soon we can leave our shacks.

In the meantime:

I’ve been playing chess against AI bots on chess.com.

Netflix recommendation:  The Bureau.   From France. A review from NPR: 

https://www.npr.org/2020/06/22/881642358/addictively-suspenseful-thriller-series-the-bureau-will-keep-you-on-edge

A reading from "Conquering the Electron."  Germanium vs. Silicon.

Bill’s Bench:

The KLH Model Twenty-one II.  Acoustical Suspension.  First receiver WITH A PILLOW!  Bad speaker? Blown AF amp finals.  Hot heat sink.  VBE Multiplier. Desitin.

Tony Fishpool’s recommended LM386 boards.  10 for 11 bucks.  Nice.  They work.  Pictured in the Amazon ad at the upper right of the SolderSmoke blog page.

Putting a digital display on the Lafayette HA-600A

Test gear trouble.  My Radio Shack multimeter getting flaky.  I many need something better.  Auto ranging? My beloved Maplin AF generator died – will have to fix. I need that thing.  Probably a bad chip.  Good thing they are socketed.

I almost forgot about SKN!  But I remembered and I made one contact with the HT-37 and Drake 2-B.    

Pete’s Bench:

Presentation to RSGB on Homebrew.

TenTek Troubleshoot.

Swan 240?  Looking nice.

SDR adventures.

MAILBAG

Bill N8ET sent me some really nice Showa 9 MHz 8 pole crystal filters. 

Kevin AA7YQ Smoke jumper!  Building a hybrid SDR.HDR rig.  Launched blog. FB

Nick M0NTV working on similar HDR/SDR project.  Great video.

Grayson KJ7UM Hollow State Design – Launched a new blog.  Very FB!

Thomas K4SWL of SWL Post blog.  Kearsarge Mountain Transmission system.  And recent events.

Peter VK2EMU Poetry.  CW poetry.

Pete WB9FLW looking at DSB rigs…

Drew N7DA  Feels not like a real ham because he hasn’t built a quad from bamboo. Which type of landscape bamboo is best for antennas?

Ryan Flowers of MiscDotGeek.Com blog is also watching the Tally Ho YouTube videos of Leo Sampson. Wants to put a WSPR beacon on the Tally Ho. 

Joe KF5OWY  Working with diode ring mixers, trying to see the mixer action on his ‘scope. 1 and -1!

Jim AB9CN sent a cool idea about how to do a 20/17 Moxon.

Roy GM4VKI – I thanked him for his article in SPRAT about putting a 2n3904 on the output of an NE602 10P mod.  Brilliant.

Roger Hayward Told him that I really liked his Dad’s recent web site updates.

Farhan – Jokingly cursed me for showing him the Oscillodyne regen of Hugo Gernsback and Jean Shepherd.  “Now I will have to build this!”

Jenny List's Favo(u)rite Things

Over on Hack-A-Day Jenny List (G7CKF)  has a really nice article about ham radio and homebrewing.  She truly has The Knack:  She got her start in radio electronics at age 9 when her parents gave her George Dobbs's Ladybird book.   

https://hackaday.com/2021/01/21/a-few-of-my-favorite-things-amateur-radio/

One of her paragraphs really seemed to capture the SDR-HDR conflict that we so often joke about: 

The age of the homebrew RF tinkerer may be at a close, at least in the manner in which I started it. Nobody at the cutting edge of radio is likely to be messing around with discrete transistor circuits in the 2020s, unless perhaps they are working with extremely exotic devices up in the millimetre wavelengths. It’s all software-defined radios, opaque black plastic boxes that deliver a useful radio experience on a computer but that’s it. No more homebrew, no more tinkering. 

Whew, good thing I'm not on the cutting edge.  It sounds kind of sad.  Oh well, that leaves more discrete transistors for us to tinker with.  

Jenny's Profile on Hack-A-Day: 

[Jenny List]: Contributing Editor and European Correspondent

Jenny List trained as an electronic engineer but spent twenty years in the publishing industry working on everything from computer games to
dictionaries before breaking out and returning to her roots.

She grew up around her parents’ small farm and blacksmith business in rural England, so making (and breaking) things is in her blood. Countless projects have crossed her bench over the years, though these days you’ll find her working with electronics and in particular radio, textiles for clothing and costume, decrepit classic cars, and real cider from first principles.

When she’s not writing for Hackaday she works on language corpus analysis software, designs and sells amateur radio kits, sits on the board of Oxford Hackspace, and is a freelance electronic design engineer and programmer.

• Hackaday Articles
• Hackaday Profile: Jenny List
• Twitter: @Jenny_Alto
• Personal Website: Language Spy

Thanks Jenny! 

Kevin AA7YQ (Montana Smoke Jumper) Launches his SDR/HDR Build Blog

 

Earlier this month I posted a note from Kevin AA7YQ describing his effort to design and build a nice transceiver that mixes the best of SDR and HDR.   Kevin has launched a blog in which he will describe the project in more detail.  He is looking for constructive feedback and suggestions.  Check it out: 

http://aa7yq.blogspot.com/.

Thanks Kevin.