ZL2BMI Double Sideband QRP Transmitter in SPRAT #191

Very cool that SPRAT had a Double Sideband (DSB)  transmitter article in its current issue (#191 Summer 2022). The author is DSB guru Eric Sears ZL2BMI,creator of the famous ZL2BMI  DSB QRP transceiver. 

I think DSB is a great way to break into homebrewing for phone.  Building a DSB transmitter is a LOT easier than building an SSB rig.  The DSB transmitter can then be converted into a DSB/Direct Conversion transceiver.   

Here is a link to 75 SolderSmoke blog posts about DSB (keep on scrolling, keep on hitting the "older posts" button): https://soldersmoke.blogspot.com/search/label/DSB

Here are a bunch of blog posts that mention ZL2BMI: https://soldersmoke.blogspot.com/search?q=ZL2BMI

Thank you Eric, and thanks to G-QRP. 

ZL2BMI @ AA7EE -- Possibly the Most Beautiful DSB Rig Ever Built

Dave AA7EE has a very cool blog post on his version of the famed ZL2BMI DSB transceiver (seen above).  As usual, Dave puts most of us to shame with his excellent non-ugly construction and enviable in-focus macrophotography.

Check it out:
https://aa7ee.wordpress.com/2012/07/29/half-of-the-zl2bmi-dsb-transceiver-a-simple-80m-direct-conversion-receiver/

I especially liked Dave's discussion of how and why .1 uF caps are used in the coupling and bypass network between the two chips.

Of course, the only thing I don't like about this rig is the, well, the chips.  Can we persuade Dave to build the earlier discrete component version of this rig?

Be sure to read the many comments on Dave's post.   Our friend Rogier comments on the beauty of it all.  Edgardo LU1AR (the Argentine wizard with the gyrocopter) chimes in.  And we see  feedback from Eric Sears ZL2BMI himself.  FB. 

VIVA DSB! 

More Info on the Cuban Jaguey Solid State DSB Transceiver

ZL2BMI Transceiver Layout (not full size here!) 

Continuing our search for information the Cuban "Jaguey" DSB rig, Trevor Woods pointed me to Dick Pascoe's QRP column in the (below) July 1998 issue of Ham Radio Today.  I think the first SPRAT article about Eric Sears' ZL2BMI DSB rig was in SPRAT 83 in the summer of 1995.  This fits well with the sequence described below by Arnie Coro CO2KK. 

I am still looking for a schematic and pictures of the Jaguey rig: If you can help in this, please let me know.  

SolderSmoke Podcast #214 is FINALLY out!

WE ARE WORKING TO IMPROVE THE AUDIO QUALITY.  IN THE FIRST RELEASE OF THIS PODCAST SOME OF THE AUDIO WAS KIND OF MUFFLED.  I TRIED TO FIX IT THIS MORNING AND I THINK I MADE SOME IMPROVEMENTS.  THE IMPROVED AUDIO IS NOW AT THE LINK BELOW.  

4 November 2019 (shockingly late!)

http://soldersmoke.com/soldersmoke214.mp3

The visit of Farhan to Northern Virginia
"I heard this guy from Southern California on 20..."
Fire Report from Pete

Pete's Bench Report
"When you know stuff, you can do stuff!" 
The CRAP rigs 
Old Boatanchors -- the Swan 120  with SUPER STABLE ANALOG VFO! 
Ten Tec rigs dial cord replaced with Chinese digi sig counter 
Pete's 500 mW encounter with a QRO curmudgeon
The ZL2BMI Challenge has Pete building crystal filters
The Left Coast Loafer CW rig 

Bill's Bench Report

ET-2 Refinements
N0WVA's Regen Receiver 
Going from ET-1 to ET-2
J-310s vice MPF-102
100 mW from a single J-310
Receiver kind of deaf -103 dbm MDS
10 contacts so far in 9 states 
THREE contacts yesterday.
Worked Wisconsin - 633 miles on 92 mW 
We are at sunspot minimum. 
"Rage, rage against the dying of the light." 
Simplicity is the real reason for CW 

IDEA:  Get those Michigan Might Mites on the air! 
Use Reverse Beacon Network to see if you are getting out 
Use SDR receivers to make contacts

MAILBAG
DL1AJG
KC6SAX
W9VNE
KA4KXX
N0WVA
Zl2BMI
AJ6BD  

The ZL2BMI DSB Transceiver

Oh man, I've been a fan of this rig for many years. I first read about it in the pages of SPRAT. Today I stumbled across what appears to be an on-line version of the instruction booklet prepared by Eric Sears, ZL2BMI. Lots of lore in there. Lots of soul in this rig.

This site has three documents describing the rig. All three are a lot of fun: http://www.mightymessage.com/

Three cheers for Eric Sears! Hip-hip...


Our book: "SolderSmoke -- Global Adventures in Wireless Electronics"http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

ZL2CTM's New Zealand Double Sideband Success

New Zealand and Australia seem to produce an amazingly high percentage of the world's double sideband transceivers.  Charlie ZL2CTM adds to the count.  He took inspiration and circuitry from DSB  hams in both countries and produced this beautiful DSB transceiver.  It is obviously -- as Charlie notes -- chock full of soul.  I definitely identify with his comment about "taming some kind of  electro-mechanical machine" and also, of course, with his remark about the feelings that come with putting a homebrew rig on the air.  So follow the advice of Charlie!  Build a DSB rig and put it on the air!  Make this your ham radio resolution for 2016!  Give it a go!    

Hi Bill:

I have been following you and Pete Juliano for many years now, and thought I would send you a photo of my 40m homebrew rig that I finished yesterday. Hopefully, it will help encourage others to melt some solder and make their own rigs. The rig is based on ideas and designs from Eric Sears ZL2BMI, Peter Parker Vk3YE and of course Pete N6QW. The aim is to make the final version relatively compact so I can take it tramping/hiking here in New Zealand.

The VFO is an AD9850 being controlled by an Arduino Pro Mini. The output is amplified to provide sufficient drive for the balanced modulator. I was using a nice 1” OLED screen to show the frequency, but that generated a huge amount of noise, so I changed to a LCD. Changing frequency is simply a matter of moving the curser left and right then using the up and down buttons to change the number. Very quick and easy. I was contemplating a rotary encoder, but I find those always seem to skip and jump every now and then. Must be the way I use them...   

The balanced modulator is a 4148 diode ring. I do have some SBL-1s lying around, but I thought I’d go with the discrete diode ring for something different. I’m using a standard electret mic and a simple single stage amp. The switch above that switches between phone and CW.

The PA is two stages; the first a 2N3053 and the second a BD139. At this stage it puts out just over 1W into a 50ohm load. I might look to add another stage and get that up to 3-5W.

The audio amp is a simple LM386. I am not running it hard out as per the datasheet as it generates quite a bit of high frequency hiss in that configuration.

Unlike Pete, I don’t have access to a milling machine to make squares to mount the components on. Instead, I use vero/strip board upside down and solder directly to the strips. This works really well for me on HF. I cut tracks with the twist of a small drill bit.

Last night I made two contacts with the rig. The farthest was 527km according to some well known mapping software. Both reports said the audio was ‘very nice’, which was great to hear. The receiver worked surprisingly well too, and I managed to hear stations in Europe.

As for user controls, you will notice that the pots, switches and plugs are all over the place. I did that to keep leads short. I like it as i feel like I am taming some kind of electro-mechanical machine to generate and receive RF.

Anyway, this little rig has a ton of soul in it and is really fun to use. There is something different about making a contact with a rig you built. I really encourage everyone to give it a go!

The next iteration will be a SDR using a Teensy. Rheslip over at Open Emitter has done some great work with that.

73s

 Charlie

ZL2CTM  

SolderSmoke Podcast 213 WE'RE BACK!

N6QW's Analog CW QRP Transceiver

SolderSmoke Podcast #213 is available. 

http://soldersmoke.com/soldersmoke213.mp3

7 September 2019

The dire consequences of our summer absence. 

50th PODCAST WITH OUR FRIEND PETE! 
THREE CHEERS FOR PETE! 

Pete's Bench Report

-- Transceiver Count:  FORTY!  
-- SDR RADIGS 
-- Colorful OLED screens
-- Pilgrims and Paisanos -- "Left Coast Homebrew SSB"
-- Pete builds a CW transceiver (see picture above)


Bill's Bench Report: 

-- Going minimalist
-- Tuna Tin 2 + Herring Aid 5 = Fish Soup 7 (and later 10)
-- My QRPp QSO with K1PUB overheard in Canada
-- Glen Yingling's ET-1 
-- Bill attempting a single transistor transceiver

SPACE NEWS

-- Antuino's Cubesat Origins. Farhan's Antuino Mods
-- Apollo 11 Anniversary
-- Possibly the best space book ever:  "Carrying the Fire" by Michael Collins
-- Chinese microsat sending eclipse pictures from the moon
-- LightSail 2 success
-- India has spacecraft in lunar orbit. 

Eric Sears ZL2BMI and Dino Papas KL0S on "QSO Today" Podcast

MAILBAG: 

ZL2PD's Sugar Cube VFO
N8WQ gets free samples
N5RWF Getting started, wisely wearing beret
VK2EMU Australian Ad for Collins Filters
W1PJE on new LDMOS PA transistors
KA4KXX Al Fresco 75 meter SSB rig with model plane engine mufflers!  

Forgot to mention:  W9TH still has manuals for whover owns Drake 2-B #4215.  Check your serial number! 

HB2HB QSO with N6ORS -- MIN-X to BITX

That's Keith N6ORS's MIN-X transceiver.  Keith explains that it has circuitry from the BITX, the Minima and even from the ZL2BMI DSB rig.  We featured the MIN-X before, when it was still outside the box:
http://soldersmoke.blogspot.com/2016/01/n6orss-min-x-crosses-pond-on-first.html

I was on twenty today with my BITX, finishing up a rather disheartening contact with a fellow who told me that he is a "checkbook operator." I was trying to encourage this fellow to build something simple -- perhaps a Michigan Mighty Mite?  He told me that he might give it a try, but only 16 years from now, after he retires.  It was like a case of the Anti-Knack!  Then Keith N6ORS saved the day by calling in with his beautiful MIN-X HOMEBREW transceiver.  We had a nice talk -- Keith mentioned the beauty of Pete's "Blue Rig." That's HB2HB (phone) QSO #5 for me.  Thanks Keith! 

Bill,
That was great fun!
I was just tuning around and heard you mentioned the Michigan Mighty Mite
so I stopped to listen and realized it was you!
Well here was my chance for a homebrew to homebrew with 'the man' himself.
I wanted to record it but missed the chance.
Here is the Min-x boxed up. the case is made from thrown away computer cases.
It runs about 70watts on 160,80 and 40 meters and about 35watts on 20 meters.
I promise to write it up, maybe even draw a schematic. hihi.
73,
Keith N6ORS 

Here' a short clip of the MINX in action:

SolderSmoke Podcast #216 Is Available: BITXs, Paesano, Paraset, ET2, Antuino, Mailbag

Bill's uBITX with HB keys and the mic that used to be the podcast mic! 

SolderSmoke Podcast #216 is available 

21 December 2019

HAPPY HOLIDAYS TO ALL! 

http://soldersmoke.com/soldersmoke216.mp3

Pete's Bench 

Sprat Article

BITX 40 Fun

ZL2BMI Rig

Paraset.   Three tubes!  Almost an ET-3!

Bill's Bench

ET-2 Adventure over,  Rig on the wall

Final QSO count. 20   3 "random" 

Last QSO with AA8OZ

Lessons learned:  100 mW not the problem. Crystal Control cramps your style. 

N0WVA regen amazingly effective.

Tried for the Sunrise Net.  Walter sent me some crystals.  

On to the uBITX. 

Accidentally wiped out calibration and BFO settings. 

Had to do recalibration and reset BFO. 

Learned a lot about the rig. 

How they did CW and how they do it now. Shift TX?  Or shift RX?  Or just shift BFO on RX? 

How all the signals end up as upper sideband.  Only one BFO freq.  Very cool. 

TalentCell 12 V Lithium Ion 3 AmpHour battery. Size of a deck of cards. 

Inspired by Peregrino -- I ordered EFHW Tuner from QRP Guys. 

Homebrew Straight Keys

Antuino upgrade 

SMT soldering. 

Back to Arduino Nano and the IDE.  

A very cool tool. 

Antuino filter analysis.

Version 6 of uBITX out. 

The "Watt Meter" DC power meter.  Very useful.  8 bucks.  LINK:

https://www.ebay.com/itm/Digital-DC-combo-Meter-LCD-Watt-Power-Volt-Amp-RC-Battery-charging-Analyzer-M/152339793114?fbclid=IwAR0u9SlZi2Dm6zOJyZt4fDTu7w_pjBIEYD_FiNfLymxtQUbMjcNHjfB17P0

SPRAT, balloons and hardcore homebrew hydrogen. 

MAILBAG

VK3HN's AM receiver.  I ordered 6kHz 455 kHz filters from Australia. 

Dean's MMM

Peter VK2EMU   Hertz not hertz. 

Ben KC9DLM LTSpice YouTube Videos

Steve Silverman  Electroluminescent Receiver Kit

Lyndon N0LFX back to listening.  FB OM

Steve M0KOV built a pill bottle variometer.  Did you get the regen going? 

Anthony VU3JVX   FB HB uBitx.  

Allison KB1GMX  Great to hear from her

Leif WB9IWT -- helped me trouble shoot my uBITX (BFO was low)

Mike EI0CL  old buddy from Azores days.  Recognized his voice on 20.  Great QSO.  

Charlie ZL2CTM's New Receiver

It is truly a thing of beauty.  

I really like that variable capacitor.  (Where did that come from?  How can I get one?)   

Charlie's calculations on each of the stages is -- as always -- really nice.  

I like the J-310 infinite impedance detector,  Charlie's use of solder wick,  the wooden base, and his decision to keep the circuitry visible.   

I also like Charlie's decision NOT to put that VFO in a metal box.  Too often we see projects that try to convince us that the receiver just won't work unless everything is hermetically sealed in submarine-like boxes.  Not true!  And Charlie's receiver demonstates this.   

Charlie is clearly keeping up the Kiwi tradition of fine homebrewing exemplified by the Tucker Tin 2,  ZL2BMI's DSB rig,  and many other FB HB projects from ZL. https://soldersmoke.blogspot.com/search?q=New+Zealand+DSB

Thanks Charlie!  Be sure to check out the rest of his YouTube channel: https://www.youtube.com/@CharlieMorrisZL2CTM

Another Great DSB rig from New Zealand

So many great Double Sideband projects come from Down Under.  There are the various versions of the famed ZL2BMI rig.   And Peter Parker VK3YE has long been the acknowledged guru of DSB. In fact, Peter sent me an enthusiastic e-mail about the new ZL DSB rig pictured above -- his e-mail arrived before the message (below) from the intrepid builder.  I detect a bit of the "Tucker Tin" influence in this rig. (But perhaps this one is more Tupper than Tucker!)  Charlie's work has graced out blog posts before: http://soldersmoke.blogspot.com/search?q=zl2ctm

Be sure to check out his video:   https://youtu.be/JsAuWGkyvmE   (and below).

Hi Bill.

You asked recently on the podcast for listeners to let you know what they had on their work bench. Well I’ve been working on a tramping (hiking) radio, which is now complete. It’s a DSB 5W rig designed for 80, 40 and 20m, as well as our New Zealand mountain safety radio system. I designed everything in LTSpice as was suggested by Pete, N6QW. That was great, as I could ‘desolder’ components with the mouse and instantly see what impact it had on the output. An amazing tool that’s free! I highly recommend it.

Once again I’ve used upside down strip board for each stage, which are tacked down onto an un-etched copper board (earth plane). That seems to work really well for me.

The rig uses an Arduino mini driving a small OLED screen and a Si5351 DDS. The Si5351 is going straight into a SBL-1, which seems to work fine too. The AF strip is a 2N3904 before a LM386, which has enough drive to run a speaker. The TX amplifier is a three stage one with shielding between each stage. It’s made up of two 2N2222A stages followed by a BD139. That in turn is followed by three simple filters, one each for 80, 40 and 20m.

All-in-all it works really well. I’ve uploaded a quick video at https://youtu.be/JsAuWGkyvmE

The next project will be a proper SSB rig using a crystal filter salvaged from an old Codan 7727. Like this one, it will use an Arduino and a Si5351.

Finally, I am certainly no expert in homebrew, but I hope my ‘dabbling’ will help inspire others to pick up the soldering iron and give it a go. If I can do it, then anybody can! There is certainly a great sense of achievement to operate a rig you built yourself.

Regards, and thanks to you and Pete for all your inspiration.

73’s

Charlie

ZL2CTM

SolderSmoke Podcast #136

http://soldersmoke.com/soldersmoke136.mp3
August 7, 2011
Travelogue: New York City
A Stroke of Luck: Lightning strikes Rome HB DC DSB WSPR rig
It's an IGY thing: Recreating the Sputnik Transmitter
ArisSAT-1 deployed. Audio Clip (Can anyone decode the SSTV in this clip?)
Summertime SPRAT -- ZL2BMI rig and the mysteries of the '602
A writer for "The New Yorker" builds a radio
June Smithsonian Magazine has a lot of Knack
Electric Radio on AM selectivity, Japanese, and the sibilant S problem
Gathering Drake 2-B Serial numbers for use with German Tank Equation
Amazon breaks into oscillation on "Atoms to Ampere" prices
MAILBAG

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics"http://soldersmoke.com/book.htmOur coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmokeOur Book Store: http://astore.amazon.com/contracross-20

SolderSmoke Podcast #132

http://soldersmoke.com/soldersmoke132.mp3

April 1, 2011
Fickle Finger of Fate: Lamp falls on QRSS Crystal
Another heroic computer repair
Sleuthing for RFI with Crystal Radios and Peter Frampton
The seductive allure of the British Regen
Watching the Space Station and the Space Shuttle
Packets from SPAAAACE
Don Vorgaard and the birth of SSB (and DSB!)
Electric Radio Magazine
SPRAT and the ZL2BMI DSB Rig
Jerri Elsworth's 555 contest (Did I win?)
73 Magazine
QSO with Mike Bryce WB8VGE
Knack Job Opportunities at Make and Hack-a-Day
Chemical Tailoring of Crystal Mic Audio Response
Pi Day!
Sling Shots, Fishing Poles, and Antenna Launchings
MAILBAG!

Kiwi Lunchbox Sideband: The Tucker Tin Two

Pete Eaton sent us links to an old article from the New Zealand magazine "Break-In."   So many good, simple rigs come to us from New Zealand!  Who can forget ZL2BMI's DSB rig?  This one is the work of Fred Johnson ZL2AMJ.  It is especially interesting and is in some ways similar to Peter Parker's "Knobless Wonder."

It uses the phasing method of sideband generation.  No crystal filters in this one.  You need TWO balanced modulators.  You have a 90 degree phase shift network for the RF (from the carrier oscillator) and a second 90 degree phase shift network for the AF from the mic amplifier.  When you combine the signals from the two balanced modulators -- viola! -- one of the sidebands disappears.  The balanced modulators take care of the carrier, and an SSB signal is launched.  That is how my old HT-37 works, and similar ideas seem to be at work in modern SDR rigs.  

G3TXQ has the complete set of Break-In articles (it includes a VFO): 
http://www.karinya.net/g3txq/temp/tucker_tin/   

Here is a Canadian article on the rig.   A "Tucker Tin" is apparently what the Kiwis call a lunch boxes (shades of Benton Harbor...).  

Thanks Pete!

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20