Innovations and Inventions in Garages and Basements

The Hewlett-Packard garage

There is a lot of inspirational stuff in this blog post, especially for those of us who work in home workshops, often in garages or basements. 

https://www.strangeloopcanon.com/p/the-mystery-of-the-garage

Thanks to HackaDay for alerting us to this. 

Some of my Double Sideband Rigs: Azores, Virginia, Dominican Republic

The above video describe a round of mods to the much modded DSB rig. And my alleged winning of the ARRL Sweepstakes (in a very elite category). 

The video above shows where I took the rig in 2014.  Bahia Rincon, Samana peninsula, Dominican Republic.  You can also see my power supply. 

Here is an article on the first DSB rig that I built, out in the Azores:  

https://www.gadgeteer.us/17METER.HTM

I think the article captures well the trials and tribulations faced by new homebrewers, perhaps with the twist that comes from being out in the middle of the Atlantic ocean.  

Mike WU2D is having similar fun with his homebrew 10 meter DSB transceiver: 

https://www.youtube.com/watch?v=uZt1LTGyoHc

I was struck by how similar Mike's early QSO experiences were with mine.  We both put our DSB transmitters on the air before they made their way into real cabinets or boxes. 

Here's mine from 2001 in the Azores: 

The Mars Helicopter and its CO2 Insulation

This video isn't about homebrew ham gear, but nonetheless I found it very interesting.  Of particular interest is the bit about their need to find a very low-weight insulator to protect the instruments from the cold of the Martian night.  Aerogel would have been too heavy.  So they just filled the instrument chamber with Carbon Dioxide.  That was their insulator. Think about that, especially those of you who still deny CO2's ability to heat up the atmosphere.  

There is a lot of great stuff on Veritasium's YouTube  channel:  

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

Grayson Evans KJ7UM Video on Homebrewing with Thermatrons

Grayson Evans KJ7UM is the author of Hollow-State Design for the Radio Amateur, a wonderful book about using Thermatrons (aka tubes, or valves) in radio projects. Buy it here:

https://www.lulu.com/shop/grayson-evans/hollow-state-design-3nd-edition/paperback/product-5mpzqr.html?page=1&pageSize=4

More info on the book is here: https://kj7um.wordpress.com/2020/12/02/hollow-state-design/ In this video, Grayson talks about construction techniques (including the use of Thermatron Me-Pads), and Manhattan construction for Thermatron projects. FB! Visit Grayson's blog: https://kj7um.wordpress.com/

Jean Shepherd has Trouble with his Heising Modulator (and his date)

This is probably Jean Shepherd's best program about homebrew ham radio.  It is about how we can become obsessed with the problems that arise with equipment that we have built ourselves, and how normal people cannot understand our obsessions.   

I posted about this back in 2008, but I was listening to it again today, and quickly realized that it is worth re-posting.   Realize that Shepherd's Heising modulation problems happened almost 90 years ago.  But the same kind of obsession affect the homebrewers of today.  

Note too how Shepherd talks about "Heising" in Heising modulation.  Heising has an entire circuit named for him, just like Hartley, Colpitts, and Pierce of oscillator fame.  Sometimes, when I tell another ham that my rig is homebrew, I get a kind of snide, snarky, loaded question:  "Well, did you DESIGN it yourself?"  This seems to be a way for appliance operators to deal with the fact that while they never build anything, someone else out there does melt solder.  They seem to think that the fact that you did not design the rig yourself makes your accomplishment less impressive, less threatening.  This week I responded to this question with Shepherd's observation -- I told the enquiring ham that my rig is in fact homebrewed, but that I had not invented the Colpitts oscillator, nor the common emitter amplifier, not the diode ring mixer, nor the low-pass filter.  But yes, the rig is homebrew, as was Shepherd's Heising modulator.    

Guys, stop what you are doing. Put down that soldering iron, or that cold Miller High Life ("the champagne of bottled beer") and click on the link below. You will be transported back to 1965 (and 1934!), and will hear master story-teller Jean Shepherd (K2ORS) describing his teenage case of The Knack. He discusses his efforts to build a Heising modulated transmitter for 160 meters. He had trouble getting it working, and became obsessed with the problem, obsessed to the point that a girl he was dating concluded that there was "something wrong with him" and that his mother "should take him to a doctor."

This one is REALLY good. It takes him a few minutes to get to the radio stuff, but it is worth the wait. More to follow. EXCELSIOR! FLICK LIVES!

Listen here:  

http://ia310115.us.archive.org/2/items/JeanShepherd1965Pt1/1965_01_29_Ham_Radio.mp3

Nate KA1MUQ's Amazing Thermatron Receiver

https://natesbasement123.blogspot.com/2024/02/thank-you-bill-dean-grayson-pete-and.html

Wow, some really wonderful work is taking place in Nate KA1MUQ's basement in California. 

-- I really like the pill bottle coil forms.  I wonder if Nate faced suspicion (and possible arrest) in the pharmacy when he asked for the pill bottles.  (I got some suspicious looks when I went I asked for empty pill bottles while building my thermatron Mate for the Mighty Midget receiver back in 1998.) 

-- The variable capacitors are also quite cool, as is the big rotary switch.   Is that for band switching? 

-- Oh  man, all on a plywood board.  Frank Jones would approve!  

-- Indeed Nate, that beautiful receiver NEEDS an analog VFO.  And we need to hear it inhaling phone sigs, not that FT8 stuff. 

-- Please keep us posted on your progress.  And of course, one hand behind your back OM.  Lots of high voltage on those thermatrons.  

Thanks Nate!  

Shuji Nakamora and his (Juliano) Blue Gallium Nitride LED

Lots of great stuff in this video:  

-- They get the charge carrier thing right:  contrary to many presentations, holes don't really move in a semiconductor.  Electrons move to fill holes, making it appear that the holes are moving. 

-- Interesting that Nakamura was so willing to defy company orders for so long. 

-- The description of the discipline that powered his inventiveness is inspiring. 

-- The way he was treated (badly) in Florida because he lacked a PhD is sadly illuminating. 

-- The discussion of corporate infighting is interesting.  

We wrote about Nakamura before:  https://soldersmoke.blogspot.com/2021/02/shuji-nakamura-inventor-of-juliano-blue.html

More Inspiring Mail! Another "First Ever Receiver was Homebrew"

Frank's Lowfer Beacon Receiver

It was great to hear from someone else who, like Scott KQ4AOP, heard his very first signals on a homebrew receiver.  That is a really wonderful way to start.  Frank's first receiver was built around the NE602 chip.  I had trouble understanding this IC but I finally cracked the code: 

https://soldersmoke.blogspot.com/2021/11/how-to-understand-ne-602-and-gilbert.html 

The picture that Frank sent is of a more recent project, this one a Lowfer receiver that picks up signals from beacons. 

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

Hello Bill, 

I just wanted to message you and tell you I really enjoyed your book Soldersmoke. I've been listening to the podcast as well.  On the latest one you mentioned a fellow who heard his first ham radio signals on a homebrew receiver, and that's how it was for me as well! There were lots of articles about using  the NE602 in the electronics magazines back in the day. I put one of the circuits together and it worked pretty smoothly... I eventually got my ham radio licence (KC8JJL) sometime in the 90's. The first time I met a ham was when I showed up to take the test!  

I don't do much transmitting these days but I still love to listen and tinker.  Here's a picture of a direct conversion LF receiver I put together... It uses an NE602 and is varactor tuned. It only covers from around 300Khz to just over 400khz  but there are still a few beacons I can hear in MI and WI. 

Frank James

We Get Mail! Red Poster? Really a Tapestry from Ecuador

Listener Tobias was laid up yesterday, following the extraction of wisdom teeth. (This seems like an appropriate follow-up to our talk in SolderSmoke Podcast #250 of sBITX "wisdom files" to correct FFT "hallucinations.") Tobias does not appear to have been hallucinating, but he was having trouble seeing what he thought to be a "red poster" in my shack.  

In fact, what he was seeing was a red tapestry from Ecuador that was sent to me by Galo Constante HC1GC way back in 1993.  I was in the Dominican Republic, running my first ever real homebrew transmitter.  Here is an article about this project: https://www.gadgeteer.us/TXHB.HTM  I think Galo was also QRP homebrew.  My log shows that I worked  him eight times from the DR. 

Mitad del Mundo =  Middle of the World (a reference to the equator). 

Here is the QSL I got from Galo: 

Here's a 2022 blog post about a resurrection of this old rig: 

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

Thanks Tobias for spotting the HC1GC tapestry and reminding me of some great QRP contacts. I hope you feel better OM.  73  Bill 

Ferdy HB9DSP's 5 band Moxon -- The Moxhorn!

 

Click on the image for a clearer view

Wow, I couldn't even build a 2 band Moxon, but Ferdy has built a 5 band version.  He told me that he had to tweak the elements a lot to get acceptable SWR's on all the bands.  20 and 17 are especially tough, because they are so close in frequency.  

More info on his great QRZ page: https://www.qrz.com/db/HB9DSP

Thanks Ferdy! 

Dean's Amazing Homebrew sBITX

 

I was kind of making fun of  it during SolderSmoke podcast #250, but later that same morning I had a chance to watch the KK4DAS homebrew sBITX in action, in person, and I must say, it was very impressive.  This may be the only homebrew sBITX in the world (please correct me if I'm wrong).  

In the picture above you can see the amalgamation of traditional superhet with modern DSP.  Even for an HDR guy like me, the result is really cool.  Once again, I experienced waterfall envy.  And the sBITX receiver sounds great. 

Dean has written up his experiences with this rig in a blog post.  Check it out for more info: 

https://kk4das.blogspot.com/2024/02/homebrew-sbitx-receiver-gound-bounce.html

Thanks Dean! 

SolderSmoke Podcast #250 Dean KK4DAS joins Pete N6QW and Bill N2CQR

SolderSmoke Podcast # 250 is ready for download: 

http://soldersmoke.com/soldersmoke250.mp3

VIDEO VERSION: (1707) SolderSmoke Podcast #250 -- With Pete N6QW, Dean KK4DAS, and Bill N2CQR - YouTube

Intro:   Welcome to Dean KK4DAS.  For 2024 Pete and I hope to jazz things up a bit by bringing in fellow homebrewers to talk about their projects.  Dean is our first victim.  Welcome Dean. 

Some good news:  Several new homebrew receivers are inhaling:  Armand WA1UQO in Richmond has an amazing looking regen.  Scott KQ4AOP in Tennessee got his DC RX working.  Mike AG5VG in Texas has been homebrewing BITX 20s and BITX 40s.  All are on the blog.  

Pete's report: 

-- Recent blog entries on filters,  SSB rig architecture, and of course digital VFOs. 

-- Phasing measurements, quadrature, and the Seeed Xiao RP2040

-- Error in QST article on early SSB transceiver.  ANOTHER ERROR!

--LC VFO on blog!  FB Pete!  

Dean's report:  

-- Tales of woe on the homebrew sBITX

-- Help from Farhan.  

-- Ground Bounce.  FFT Hallucinations.   Wisdom files.

SHAMELESS COMMERCE DIVISION:   

-- Whenever you are tempted to buy something from AMAZON, just start at the Amazon symbol on the right side of the page.  We get a cut from Bezos, and it doesn't cost you anything.  

-- You can try to do the same thing with E-bay.  We are finding a lot of great parts there. 

-- If you see a SolderSmoke post on Facebook,  please Like and forward. 

-- Become a patron!  Go to the Patreon page.  We put the money to good SolderSmoke use. 

-- Visit Mostly DIY RF and buy a PSSST kit!  

Bill's bench:  

-- Building yet another BITX dual bander.  15-10 again. Tried to use a 25 MHz filter left over from the earlier project, but I had to build another.  Built a new VFO using the variable cap and anti-backlash gear recommended by Pete.  Was a bit tough to get the receiver sounding good.   Had a diode ring as the second mixer, but went back to a singly balanced mixer. 

-- 10 meter AM -- Thanks to Jerry Coffman K5JC for mod. 

Other topics: 

--Counterfeit chips.  Why? 

MAILBAG: 

Wes W7ZOI 

Jim Cook W8NSA  Transoceanic BFO

Grayson KJ7UM -- Vintage Computer Museum

Chuck Adams --Glad to hear that Chuck is doing well.  

Frank Harris  K0IYE --  NO CHIPS!!!! 

ED DD5LP  Antenna software

Eldon KC5U  10 AM We  made a contact

Joh DL6ID  10 AM   

Phil   W1PJE of MIT   10AM   Where is L5? 

Bob WP4BQV now in UK 

Dino Papas KL0S in Wilmington   Reverse Polarity protection. 

AA7EE Dave Richards  Liked Armand's receiver

Rogier PA1ZZ  

Jonathan-san W0XO  Listened to my ET-2 CW Whoop,whoop

Nick M0NTV  Great videos from Nick the Vic

Will KI4POV  Working on his own SSB rigs.  

John West -- Who is the South American ham who made his capacitors and heat sinks? 

Ed KC8SBV  Working on DC receiver, experimenting with FETs 

Mike WN2A great contributions.  Si5351 sole source danger! 

Nick N3FJZ -- watch out for dead bands when testing receivers! 

Don KM4UDX encouragement from new Prez of VWS

Dave K8WPE Likes QF1 Cap backlash.  Says I'm getting soft! 

Dave WA1LBP My fellow Hambassador, from Okinawa USMC Sergeant with a workshop.