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

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.  

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. 

Summer Solstice -- EITs. Solar Tsunamis. Strange Falcon 9 Spirals Seen in New Zealand

 

Forbes has an interesting article that may help explain the poor Cycle 25 propagation that were talking about in SolderSmoke podcast #238: https://www.forbes.com/sites/ericmack/2022/03/28/an-increasingly-active-sun-is-now-producing-solar-tsunamis-and-sending-flares-our-way/?sh=613e1dd1fbfd 

And Space Weather website has an interesting piece about some really strange SpaceX Falcon 9-related phenonmenon: 

https://spaceweather.com/archive.php?view=1&day=20&month=06&year=2022

Early Radio in New Zealand, and "The Knack"

 

Thanks to Thomas K4SWL of the SWLing Post for alerting us to this gem.  Listen to Sarah Johnston's program describing the origins and early years of broadcast radio in New Zealand. 

https://www.rnz.co.nz/national/programmes/smart_talk/audio/2018821216/voices-in-the-air-sarah-johnston-on-100-years-of-radio

This wonderful recording and article reminded me of a bit of ham radio history involving New Zealand,  and someone who was involved who had a surname similar to mine.  The ARRL book "200 Meters and Down" by Clinton DeSoto reports on page 91 that on May 22, 1924, radio amateurs for the first time made a contact between New Zealand and South America.  Carlos Braggio operated rCB8 in Buenos Aires.  In New Zealand, J.H. O'Meara was at the key in Gisborne. 

Writing of the early amateurs,  DeSoto wrote (on page 92): 

 "Why did they do it?  None but one of them can know, and only he would know the feeling of driving ambition, the relentless call of work to be done, the gnawing discontent that hungers for accomplishment; it would be hard to put into words. The strange thing is that there were folk, everywhere on earth it seemed, who had that urge." 

"The gnawing discontent..."  That is what Jean Shepherd had when he couldn't get his Heising Modulator to work properly.  We've all been there. 

The last line in the quote from DeSoto's book speaks to one of the major themes of this blog and of the SolderSmoke podcast:  the way in which people all around the world got interested in radio in much the same way.  So many of us, all around the world,  often at age 13 or 14, suddenly got interested in radio.  We all had (and have!) "The Knack."  This is really very nice -- it is something that we have in common, something that pulls us together. 

SSB History -- The Tucker Tin 2 (and 3) with a 1961 Recording. Hallicrafters FPM-200 Video by W9RAN

There is so much important SSB history in this video from Bob Nichols, W9RAN.  I liked all of it,  but the on-the-air recording of a 1961 transmission from a Tucker Tin 3 was really amazing.  Check it out. 

Here is the 2014 SolderSmoke blog post about the Tucker Tin 2. You can see the 1961 schematic here: 

https://soldersmoke.blogspot.com/2014/09/kiwi-lunchbox-sideband-tucker-tin-two.html

As you can see this is a very simple phasing-type SSB rig.  The SSB generator is crystal controlled at the operating frequency.  

Thanks to Bob W9RAN, and thanks to Peter Parker VK3YE for posting about this video on the SolderSmoke Facebook Page. 

 

The Chatham Islands

ZL2CTM's Simple SSB Transceiver

Congratulations to Charlie Morris ZL2CTM for his first contact with his Simple SSB rig.  

There are so many cool things in Charlie's video, starting with his mention of having been woken up early (2 am)  by the very strong earthquake off New Zealand.   Exhibiting true homebrew spirit, Charlie apparently went straight for the shack and worked on his rig.  FB OM. 

Al fresco!  I love the spacious layout on the board and the obvious division into stages.  And I like the wooden board that holds it all together. 

I like the idea of two bandpass filters -- this is simpler than switching one from transmit to receiver.  

Hooray!  Homebrew diode ring mixers!   Yes! 

I think Charlie follows the UK convention with his T/R switch -- they have up as off.  I may be wrong but I think most US homebrewers have up as on, and up as transmit.  Cultural differences. 

Notice Charlie touch-testing the heatsink during that first QSO.  We all do that. 

I like the 24 volts on the IRF-510 drain.  Allison always said that IRF-510s run better at 24V than they do at 12V. 

Of course I disagree a bit on the issue of analog VFOs. But this is just a matter of personal circuit preference. 

Charlie's calculations and notes are really wonderful.  His candid discussion of impedance matching is especially useful.    I think his use of loose-leaf  sheets of paper is wise and it paves the way for a useful folder for each HB rig. 

Here is the introductory video for Charlie's Simple SSB project: 

https://www.youtube.com/watch?v=BgQUG0AImKY&list=PLxU5OX0SLgIPdYj_MZG03CeimbRU6Btml

Here is Charlie's 10 part video series on his simple SSB rig: 

https://www.youtube.com/playlist?list=PLxU5OX0SLgIPdYj_MZG03CeimbRU6Btml

And here is Charlie's YouTube channel: 

https://www.youtube.com/c/CharlieMorrisZL2CTM/videos

Thanks Charlie! 

A Song Fom Dexter ZL2DEX

From a post on on "ZL Amateur Radio & Friends,"  in response to a complaint about the lack of activity (with apologies to Paul Simon):  

'50 Ways':

"Get on the band, Stan,
Trigger the mic, Ike,
Tap your key, Lee,
Listen for me.
Paddle the bug, Doug,
Watch the waterfall, Paul,
Just QSO, Joe,
when conditions agree."

73

Dex, ZL2DEX

ZL2CTM Charlie Morris on "QSO Today" with Eric Guth 4Z1UG

Eric Guth 4Z1UG had a really nice interview with our friend Charlie Morris ZL2CTM.  Charlie shared with Eric a lot of wisdom about how to homebrew radio gear.  I especially liked Charlie's comments on keeping most of his rigs on the wooden prototype boards.  He said something important when he talked about the benefits of taking a break from a difficult problem, then coming back to it with a rested and refreshed mind. I noted, however,  that he said most of these frustrating problems have to do with software.  

I got got several chuckles out of Charlie's comments on the difficulty of building stable analog LC VFOs (here he seemed to be channeling our good friend Pete Juliano).  I chuckled because as I listened I was happily building the analog LC VFO for my Q-31 Quarantine receiver.  The centerpiece of this project is a variable capacitor that Pete gave me;   Pete took it out of an old  Galaxy V transceiver.   Believe me guys, no rotary encoder could possibly look as nice or have as much soul as that capacitor from Pete, with all its gears, reduction drives, and anti-backlash mechanisms.  It even smells of machine oil.  Call me a Luddite, but I will stick with the coils and capacitors.  

Listen to the interview here: 

https://www.qsotoday.com/podcasts/zl2ctm

Thanks to Charlie and Eric. 

ZL2CTM's Inspirational Tramping Transceivers (videos)

Charlie Morris ZL2CTM is working on portable (tramping) transceivers. Check out his amazing and innovative enclosures and circuit boards.  Really nice. A great way to keep that beautiful circuitry visible. 

More details on Charlie's blog: 

https://zl2ctm.blogspot.com/2019/12/40m-ssb-tramping-rig.html

Thanks Charlie.  Happy trails!  73

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  

ZL2CTM's Homebrew Transceiver Project

Wow, Charlie has a lot of very cool ideas in this initial video.   Some suggestions: 

-- With the IRF-510 in the final, beef up the heatsink, and follow Farhan's lead by including an option for 24 volts on the drain.  That would take you  up to 20 watts or so (for those who are so inclined). 

-- Could that Teensy SDR board work at the IF frequency?  If so, consider putting it ahead of the crystal filter.  This would enable us all to join the Waterfall Signal Purity Police Force. 

-- I love the OLEDs too, but I found them to be noisy.  I minimized the noise with shielding around the OLED and active decoupling on the power line to the AF amplifiers.

More of Charlie's work here: 

https://plus.google.com/107506245856154702088

ZL1UEM'S Tiny OLED Si5351 Arduino VFO

Hugh ZL1UEM has come up with a very creative way to take maximum advantage of the small size of the Si5351 board, the Arduino, and the OLED display.  He even has the rotary encoder in there.  Look carefully -- he uses both sides of the board.  Very nice. Thanks Hugh!

Hi Bill,

First let me say that I have been an avid follower of the SS blog and podcasts since the days of your podcasts involving Mike KL7R.

Like many others I was tempted to purchase the $49 surface mount module from HF Signals.  As a keen home brewer I felt guilty about employing a prebuilt board but excused my decision on the grounds that I would build a DDS and other accessories myself.

In addition to follow the SS blog I also check Pete's blog regularly and was excited by his OLED VFO for the Bitx40.

I constructed it on a small double sided matrix board with plated through holes.  A bit of noodling led to the layout shown in the photos.  There is only one board with components mounted on both sides.  The board came to life on the first power up but the text spilled off the bottom of the display.

I assumed that the sketch that I had downloaded from Pete's blog was for a different OLED module.  I knew that he had also used a yellow/blue OLED, the same as mine, previously so emailed him requesting a sketch for this OLED.

I was taken aback when he informed me that the sketch I had was the same for both the dual colour OLED and the black and white one too.  Pete suggested that I swot up on the use of OLEDs generally and that perhaps I should first experiment with the text size to begin with.  He also offered some advice about the mapping of the screen.

I soon discovered that the text size was not the cause of my grief and that I needed to look elsewhere.

I first tried running the ssd1306_128x64_I2c sketch from the sample sketch folder and was rewarded with the message "Height incorrect, please fix Adafruit _SSD1306.h".  A search of the Internet revealed that I needed to edit the .h file and find "#define SSD1306_128_64" which was commented out and uncomment it and make sure that the other two options, _32 and _16, were commented out.

My next problem was how to edit the specified .h file.  I tried notepad but the text all ran together.  Another internet search revealed that Notepad++ was a suitable choice and it did indeed cut the mustard.

A reload of the sketch completely restored the display to full functionality.

All this may be obvious to many but it was all new to me and if I had not been prompted by Pete l would not have had learnt so much and would not have had the same sense of achievement when it all came together.

Many thanks to you and Pete for providing a focus for my hobby.

73's
Hugh ZL1UEM

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

Cool Jazz from New Zealand as Heard on a Homebrew Superhet Receiver (VIDEO)

I'm making slow but steady progress on this one.  The origin of the project was the beautiful National HRO dial and gearbox that Armand WA1UQO gave me. 

I decided to use a 455 kHz IF because;
1) That was the IF of the old HRO receivers (the ones that won WWII)
2) I had a nice TOYO CM455 crystal mechanical filter that would be good for SSB.
3) I figured it would be easy to add in a wider filter that would be good for AM shortwave listening.
4) I like to keep the IF below the frequency of the VFO.

The wide filter turned out to be harder than I thought, but I think I have finally achieved the selectivity I was looking for.  I'll have a switch on the front panel that will allow me to go from "AM-Wide" to "SSB Narrow." The switch will change the filters and the detectors, and will turn the BFO on and off.

Still to do:  I need a high-pass filter to knock down RFI from nearby AM broadcast transmitter. And an RF gain control would be nice.

I'm really glad Radio New Zealand is there.  It provides welcome relief from the shortwave fire and brimstone.   Radio Romania is also doing a fine job on shortwave.

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! 

Radio New Zealand Booming in on 7245 AM

The day is off to a good start here at SolderSmoke HQ, with Radio New Zealand booming in on my homebrew Mate for the Mighty Midget receiver.  I was listening from around 0900 to 1030 UTC on 7245 kHz. Once again we see that The Radio Gods favor homebrew receivers. Gray line propagation also played a role.  

Above we see a technician at work at RNZ in 1945.  More historic photos here:
http://www.pcc.govt.nz/About-Porirua/Porirua-s-heritage/Porirua-s-suburbs/Titahi-Bay/Historic-site--Radio-New-Zealand-Transmission-Station

Listening to New Zealand on the Barbados RX via the Gray Line (40 meter CW)

John: 
For the last couple of mornings you have been coming in quite strong on 40 meters around dawn here.    Attached is a short video from today.  I am listening with a homebrew superhet receiver:

http://soldersmoke.blogspot.com/2016/05/a-lot-of-soul-in-barbados-receiver.html

73  Bill N2CQR

Hi Bill,

Thanks for sending the video clip.

It’s really made my day!

I’ve sometimes wonder what I sound like at DX now I know.

The IC7410 sounds quite respectable and the sending is reasonably decipherable.

Interesting about the receiver.

The signal seems to stand out well from the noise.

Really well done. But then that’s what ham radio is all about.

We all enjoy radio and  we all like to enjoy the various aspects to the hobby.

Modes, antennas ,QRP whatever.

It’s great fun.

It would be good to have a QSO. perhaps some time soon?

Thanks again,

Very Best 73,

 John ZL1ALA

KiwiSDR

https://www.kickstarter.com/projects/1575992013/kiwisdr-beaglebone-software-defined-radio-sdr-with?ref=video

Sputnik Replica Transmitter, an "Error" in the Sputnik Schematic, and Why 20.005 MHz?

Mark K6HX pointed me to very interesting Hackaday article on Frank PA3CNO's Sputnik transmitter replica.  As blog readers will recall, we went through a period of Sputnik-mania a few years ago:  http://soldersmoke.blogspot.com/search?q=sputnik  Chief Designer Comrade Mikhail Rainey AA1TJ sent me some of the Russian tubes (like those pictured above). 

The Hackaday article pointed to our post reporting that Oleg RV3GM had found the schematic:

http://soldersmoke.blogspot.com/2013/04/sputnik-schematic-found.html   Stefan reports that PA3CNO found "an error" in the original Soviet schematic:

http://www.radio.cc/post/Franks-power-supply-for-sputnik    A mistake you say?   HAH, I say!  Hah!  This must have been part of a sinister commie plot to prevent the capitalist imperialists from ever being able to reproduce the glorious transmitter of the Soviet people.  They almost succeeded. 

Just kidding.  

In the course of looking through our old Sputnik posts, I came across a question I posted:

I have a question: OK so the crafty Soviets picked 20.005 MHz for some good reasons: Being so close to the WWV freq, it would be easy for hams and SWLs to find it with precision. In the November/December 2007 issue of "Break In" (from NZ -- thanks Jonathan-san!) ZL3DW notes that this frequency selection would allow a receiver set to exactly 20 MHz to "produce an audio tone plus or minus the Doppler shift without ever going through zero beat." But zero beat with what? Most of the receivers out there would not have had BFOs, right? So the Soviets wouldn't have been using ordinary CW, right? Were they using AM, with the beeps produced by an audio oscillator modulating the carrier? 

Was their diabolical plan to use WWV as the BFO for those using ordinary AM SW receivers?   If so, a 5 kHz separation from WWV seems to be too much right?  Especially when the Doppler shift on approach would push the frequency up a bit. Maybe they just chose this freq to make it easy for listeners to find -- just a bit above WWV.  Comrade Rainey surmised that they were keying the PA stage -- the oscillator "backwave" was at times audible on the ground.

What do you think Comrades?

DSW and 73.