DONE! Jan's AMAZING Mate for the Mighty Midget Receiver

Hi Bill,

  

Finally the Mate for the Mighty Midget is finished, just in time for the G-QRP Valve Day 12-13^th of November.

Got the LO fixed for 40m by lowering the parallel capacitor from 150 pF to 100 pF.

Also the 68 pF series capacitor was lowered to 33 pF for some more band spread on 40m.

It now receives from about 7.0 to 7.4 MHz and from 3.45 to 4.0 MHz

Had to exchange C1 in the end, the one used initially quit every now and then.

I only had a large 3 section variable in the junk box covering 10-550 pF, which works fine now.
For the lower end of 80m I had to add additional 47 pF next to the 47 pF trimmer caps, so there it is about 600-650 pF max!

At the high end of 40, it is also just not too much.

The meter was used as a position indicator for C1.

Tried several ideas, but with no separate tube for AGC, I couldn’t get it to work as a S- meter

Read something about audio derived AGC, maybe this is worth a try.

 

The BFO can be switched off for AM reception.

Simultaneously the input on the mixer side of the crystals is disconnected but still coupled by some capacitance of the switch wires.

AM reception is possible, but not very good.

Need to find a better solution which doesn’t degrade the crystal filter properties to much.

(By the way, the detector regen. control ads about 4 dB to the AM sensitivity)

The receiver will mainly be used for CW/SSB reception, so maybe it stays this way for a while J

 

I hooked it up to the W1TS transmitter, which was very loud.

Didn’t foresee a T/R relay (learned a lot from this project ;-)  ), so added this one between the front plates next to the RF and audio gain control.

The quit down everything a little, the RF gain pot is lifted of ground as suggested by James, N2EY at QRZ.com.

It helped a lot, but was still too loud if tuned exactly in the bandpass of the crystals.

The T/R relay now also switches an adjustable potentiometer at the input of the audio pre-amplifier.

 

The dial cord has no lag, and works very well for fine tuning.

Unfortunately the reduction drive went from 1:19 to 1:9…, the tuning capacitor only has a 180 deg. span.

Something to remember for the next receiver.

 

It’s a nice little receiver and quite stable after warm-up.

The only extra luxury a next receiver will have, is AGC.

But with no AGC it’s easier to tune the antenna tuner by ear J

There’s now a complete homebrew station here, antenna, feeder, tuner, receiver, transmitter, power supply, al home made J

 

About the Mystery Hole….

If you haven’t guessed it by now, or Pete hasn’t told you, it is revealed in one of the pictures below.

 

I also made a little video:

 

https://www.youtube.com/watch?v=4-STxQI36_s

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

I.G.Y., The Nightfly, Donald Fagen, Jean Shepherd and SolderSmoke

OK, so from time-to-time we  talk about IGY, the International Geophysical Year. I was born during that scientifically momentous period.  A lot of cool stuff happened.  Amazing propagation conditions too.  So for a while (around SolderSmoke 149) I was using the opening bars of Donald Fagen's song I.G.Y. as the intro for the podcast.  That song comes from Fagen's album Nightfly.  The album cover appears above.

This morning I got two e-mails from Steve N8NM about another connection between SolderSmoke and IGY.  At first I thought he was pulling my leg.  But  before I show you the e-mails, let me show you another picture:

That's Jean Shepherd.  Can you dig it?

Steve writes:

Hey Bill! 

I'm Listening to #149, where you introduced Donald Fagen's "I.G.Y" as the new theme song.  Have you heard that the protagonist on that album is based on none-other than Shep, K2ORS.  Don't know if that's necessarily true, but the album title (The Nightfly), Fagen being from NY, and the era depicted certainly make that plausible...

I guess it's factual - This is from an interview Fagen did with New York Magazine:

Your first solo album, The Nightfly, was inspired by fifties jazz disc jockeys. Which ones were your favorites?
Symphony Sid was very popular. Mort Fega was probably the best all-around jazz D.J. Ed Beach on WRVR would do this very scholarly afternoon show, and I’d listen to that when I came home from school. But the figure of the Nightfly was based more on a guy who didn’t play jazz records, Jean Shepherd. He was a monologist who used to just talk and tell stories and say funny things. He was a social satirist.

Speaking of Shep:  You've done him proud, not only in your HB radio efforts, but in proving yourself to be a very capable monologist for the several years between Mike's passing and Pete's arrival.  Three Cheers for Bill!  Give that man a brass figlagee with gold leaf palm!

73!  Steve N8NM

By the authority vested in me by having once spoken to Jean Shepherd, I award Steve Murphy N8NM, the coveted Brass Figlagee with Gold Leaf Palm.  

EXCELSIOR!  

TRGHS

Farhan on What's New in the BITX 40 Module

Writing to the BITX e-mail group, Farhan provides some very interesting information on the philosophy behind his new BITX 40 module, and on how it differs from earlier BITX designs:

The new builders are often caught in a catch-22 : to get on air they need to build a rig from scratch. but to build a rig, they need lots of experience. A way out was to provide working boards where we can get on air quickly, and then start improving and modding the circuit. this is the spirit behind the new boards. Consider them like you would consider a raspberry pi or an arduino : simple, working circuits around which you can grow your own radio.

In the new bitx boards, I have tried to keep as close to the original bitx as I could. however, there are a few departures that I thought the bitx builders here would like to know about.

i have to admit though, strangely, i am less familiar here with bitx than many others on this form. arv, leonard, dan,  andy and others have build far many more version than I did. I just happen to be the first one to build a bitx. this as much an acknowledgement of their inputs. without all you folks, bitx would not have had the kind of traction that it now enjoys. I suspect that it is the most built transceiver in the world.

So, here are the changes from the original bitx.

1. SMD

The SMD components make for virtually error free boards assembly. We used the biggest sized SMD components. In fact, the resistors and capacitors are about the same size as a quarter watt resistor that is soldered standing up. They are very easy to desolder without messing around with the desoldering wick and solder pumps. All you do is to lay the soldering iron's bit on the component such that the flat end touches both sides at once and after a few seconds just drag the component away. I soldered the sample boards with my regular, 2 dollar, 25 watts iron without using a magnifier (I wear reading glasses). 

1. 40 Meters

It is just that with the sunspots fading away, 20 meters in the tropics is far less active than before. Many of the us South Indian hams hang out on the lower end of 40 meters every morning and evening. Hence, the choice. That doesn't mean that i can't be converted to 20m! There are several ways to change to 20 meters. Keeping the VFO same, change the crystals (and hence the IF) to 8.833 MHz and rework the band pass and the low pass filters. I will work out the details in a few weeks and post them here.

2. A new bandpass filter

The original bandpass filter was quite lossy. I didn't know how to use any CAD tools when i sketched it. I was actually on a long haul flight when I designed that filter. The new filter configuration is very interesting one. I saw it on PA3AKE's site. This is a triple tuned circuit with very good out of band attenuation while maintaining very low loss. 

In the last then years, ecomm has made it possible for us to globally access good quality toroids anywhere in the world. Hence, we have used T30-6 toroids with excellent low loss. I measured it at just 2 db, the original had more than 6db loss.

3. VCO

The original oscillator on the BITX used a variable capacitor. These were noisy, and often of inferior quality. In any case, they are no longer available. Instead, we have used a varactor diode for tuning. The greater benefit of using a varactor to tune the oscillator is that the tuning control only carries a DC voltage. You can install it anywhere. If you need finer tuning control, you can add a second lower value tuning pot in series with the main tuning pot. It is easier to add FLL to a VCO.

4. Audio muting

The original BITX used just a switch to move from receive to transmit. The receive voltage charged receiver's audio preamp's decoupling capacitor and it took time to discharge. this kept the audio preamp active even on transmit and caused a very sharp audio noise on the transmit change over. Now, the other section of the T/R relay is used to cut the audio off to the LM386 as soon as transmit line is energized.

5. A better T/R system

The original bitx didn't have a PTT. this one has two relays to switch the linear amplification chain in and out of the circuit, mute the audio and change over the antenna. These changes lead to a very stable linear amplifier and smoother change over. 

6. Mic amplifier

The original mic amplifier easily saturated. The new design, thanks to dan tayloe, has a better head room and provides very clean modulation.

7. The fixed BFO

Though the PCB has the provision for a trimmer and an inductor to pull the crystal frequency. I discovered that with five matched crystals, if you used 4 in the ladder filter, the fifth's frequency fell right into the perfect sweet spot for LSB work. You might need to add the trimmer and an inductor back for USB work.

8. DDS connector

To use the DDS, you will have to remove L4 (the VFO inductor) and inject the DDS/PLL output into the connector provided.

There are some smaller mods that people can try out:

* The current in the receive amplifiers can be reduced if you don't have any radio hams in your neighbourhood who run kilowatt amps. 

* The capacitor between pins 1 and 8 of the LM386 can be removed if you prefer headphones to speakers. 

VK3HN: SOTA, HB, SSB, and QRP FB!

Peter VK3YE sent me the link to this amazing site.  Wow, Paul VK3HN does great work, both with the homebrew rigs and in describing his work on them.  Check it out: 

https://vk3hn.wordpress.com/2016/10/25/summit-prowler-one-a-homebrew-7mhz-ssb-qrp-transceiver-for-sota/

Great stuff.  Thanks Peter!  Thanks Paul!

Video of BITX 40 Module in receive mode

A Package from Hyderabad: Farhan's BITX 40 Module Arrives in Virginia

I am having a really EXCELLENT radio morning here at SolderSmoke East coast HQ.  I made some progress on the Armand HRO receiver -- just squaring away some of the too-long leads and improving the shielding a bit.  Then I was looking out the window as the mailman arrived.  What was that little box he was leaving us?  Wow! A box from Hyderabad!  The BITX 40 module arrived, wrapped in a very interesting piece of Hyderabad newspaper. Very FB. Thanks Farhan.  I will surely be writing and talking about this rig in the weeks to come.

UPDATE:  I just realized that the BITX module fits very nicely into a TenTec TPC-45 cabinet that Armand gave me a while back.  TRGHS.

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.

The Last Hallicrafters Transceiver...REBORN! TWICE!

Pete Juliano and his colleague Giovanni Manzoni led me this morning to the happy land of Hallicrafters hybrid nostalgia.

It all started with Pete's latest blog post:  
http://n6qw.blogspot.com/2016/10/more-junk-box-rigs.html

I admit that I had never even heard of the Hallicrafters FPM rigs.  Pete's (uh, I mean Giovanni's) video show's Pete's junk-box rebuild of the old rig.  Very nice.   Note the presence of the Si5351...

I needed more background info, so I turned to YouTube.  This led me to more old friends:  Dale Parfitt W4OP has a really nice video of his rebuild of the Halli FPM rig (see above).  From his video we learn why Dr. Juliano prescribed a dose of Si5351 for the patient:  Dale tells us that VFO instability was a major problem with this rig.   Dale fixed his with the addition of an X-Lock board from yet another friend of SolderSmoke: Ron G4GXO of Cumbria Designs. 

Dale really out-did himself by building an add-on accessory box for the FPM.  Very nice.  I especially liked the addition of the W3NQN passive audio filter for CW.   I always have misgivings about adding audio filters to Direct Conversion receivers -- this will reduce QRM, but you are still listening to both sides of zero beat.  But when you add a sharp CW audio filter to an SSB superhet you will end up with true "single signal reception."  FB Dale.  

Please send Pete Juliano and Giovanni Manzoni some positive feedback and words of encouragement.  Please urge them to keep up the good work on the blog and the videos.  Theirs is sometimes a lonely task -- without feedback it can sometimes seem like putting messages in a bottle and throwing them into the digital sea.   Please let them know that their work is being seen!  Leave some positive comments on Pete's blog.  (No snark please -- The Radio Gods will retaliate if you harsh N6QW's mellow.)

Oz Tektronix 'Scope Repair (in Juliano Blue)

Rob is a braver ham than I.  When my Tek 465 quit, I tried to fix it, but quickly chickened out.
Very nice that he painted his in Juliano Blue.

Dear Bill and Pete, 

I do enjoy your podcast, and I must present an offering to the "Gods of Homebrew", 

An on-line find of an old Tek 545 oscilloscope presented a chance to enjoy the warmth of 100+ tubes (once repaired)

The outside was heavily scratched, the inside looked like a chicken coup, but no major bits missing or broken. 

Lots of cleaning, testing all tubes,(using the excellent uTracer tube tracer),  replacing the broken 3, remounting the cooling fan, lots of reading about tube oscilloscopes, adjusting the trigger circuit, rebuilding 3 electrolytic power supply capacitors, sandblasting the cabinet and a coat of BLUE paint. 

Voila,  the joy of (visual) oscillation!     (1MHz 2V p-p)

Rob VK5RC

Colin M1BUU's New Receiver Project

Hi Pete,

Just checking in :-)

I have actually been melting solder recently. I decided to build a little CW receiver. I love my regenerative RX that I built as a teenager, but after all these years, I'm tired of constantly tweaking the controls!

My project is a 20m CW only superhet receiver with a 9MHz home brew filter. I'm using the SI5351 for the oscillators. I originally thought I would cover multiple  bands, but for now I have the parts for 20m coverage. I might tinker with other bands at a later point.

I'm using your LBS code on the Arduino, the one for 20m with 9MHz IF. I haven't applied power to the rig yet but it's not far off fully built. I tweaked the Arduino sketch using my Uno and tonight I have successfully transferred the code to a Pro Mini. (Code went into Pro Mini on first attempt - amazing!).

73 for now,

Colin M1BUU

Beautifully Ugly! A Homebrew Receiver from the Netherlands (video)

This one is similar to the receiver I've been working on:  middle of the HF band, discrete components, all analog, 455 kc IF, wooden chassis, eclectic circuit boards.  Very cool.

The builder is Ko Tilman.  His YouTube channel is here:
https://www.youtube.com/channel/UCqe1Y4StR9cZ8BQDWuoMq9w

I came across Ko's channel when I was looking for a circuit for an AM detector.   I have been  experimenting with the standard one diode and two diode (Germanium) circuits, but the receiver doesn't sound very good when using these circuits.   Any recommendations for something a bit better (without getting carried away with complexity)?


About Ko Tilman:

Ko Tilman (1955) lives in the Netherlands and is active in electronics since 1967. His focus is on analog electronics, audio, shortwave radio's, small (solar) energy systems and measurement and control systems. He is the author of "Retro Radio", Isbn 978-90-5381-234-1, published by Elektor International Media in the Netherlands. In this book (Dutch text) you will find several simple schematics from Shortwave radio's (2 MHz - 16 MHz), including radio's with SSB reception. His long time knowledge about small audio systems (for household use) is available in his book "Schematics 2, audio amplifiers and loudspeaker boxes ", available on this website (a summary of the content is visible). Also in an E-book format: Isbn 978-1-4475-7336-4. In the past (2008-2010) he was active on You Tube under the name "radioam232", now he is active on Youtube as "radiofun232". A free download from the activities in the "radioam232" period is available on this website in the content "blueprints 1".

Ko's Books: http://www.lulu.com/spotlight/radioam232

Smoke-Free! On the Air with the W1REX Dayton Hamfest Buddy

After the Dayton Hamvention, our ace correspondent Bob Crane (W8SX) sent me the "Hamfest Buddy" kit that Rex Harper W1REX had put together and used in "The World's Biggest Build-a-Thon."

It is a single 2N2222 crystal-controlled oscillator for 20 meters.   All the parts are plug-in -- no solder smoke is released.   Mine went together in about 15 minutes and fired right up.  You can see it above.  It runs off the 9V battery. I had to hold it down with tape.   You can see the key button in the lower right.  That little inductor in the foreground is used to shift the frequency a bit.  I had to remove the 10K resistor in the emitter circuit because with my antenna the circuit was going into low-level oscillation even in key-up.  With the 10K resistor removed, this problem disappeared.

I hooked it up to my 20 meter dipole and called CQ.   With only about 60 milliwatts into a dipole under poor conditions, I really didn't think I'd get any answers.  But I figured the Reverse Beacon Network might pick me up.  It did:

Thanks Bob!  Thanks Rex!

HB2HB! KW4KD and N2CQR (video)

A couple weeks ago I ran into Jim KW4KD on 40 meter SSB.  Jim is in Chattanooga, Tennessee.  He was running a modern "black box" rig, but he mentioned that he had on the shelf two complete homebrew stations, one of which was for 40 meter SSB.  He hadn't used this gear in 40 years.  I encouraged him to blow the dust off and get it on the air.  Yesterday, Jim did just that.   We met up on 40, first at 1730 local (my time) and again at 1930.   Excellent!  Another HB2HB contact.  Check out the video (above).   Thanks Jim.

If you run into someone who mentions having some old homebrew gear, encourage them to blow the dust off and get it on the air.

Jim's SSB rig:

The Invention of the Reflectometer: Naval Research Lab Report #3538

Dennis Klipa N8ERF has been doing great work exploring the technical intricacies of the humble SWR meter (and believe me, there are intricacies).   He's also been looking at the history of this invention. 

This summer, Dennis and I came across the April 1964 issue of Popular Electronics.  On pages 74 and 75 of that issue we found a clue that seemed to point to the origins of the device:  the article referred to Naval Research Lab Report #3538 by O. Norgorden,  published on September 15, 1949.  This may be the paper that led to the widespread use of SWR meters by radio amateurs.

Surprisingly, this important paper was not to be found on the internet.  Exhibiting an admirable dedication to the preservation of an important element of the radio art, Dennis wrote to Naval Research Lab and purchased from them a copy of the report.   Unfortunately, the version Dennis got had been copied and recopied so many times that it was hard to read.  So he went the extra mile and re-typed it. 

With his permission, I am giving this article its internet debut by posting it here:

http://soldersmoke.com/SWR N8ERF.pdf

Three cheers for Dennis Klipa for unearthing this important piece of radio history.

From the Wizard of Wimbledon: Matchbox Junkbox Rig

Dear Bill

I hope that life’s treating you kindly over the left side of the pond. Your latest podcast really resonated with me as I’m hugely fond of junk box projects on a rainy afternoon. Fortunately Her Majesty’s weather men are generous...

Spy gadgets have long been a fascination of mine, particularly those disguised as harmless everyday objects. I remembered a Soldersmoke blog post a few months back showing a radio hidden inside a book. That got me thinking… then one rainy afternoon I stumbled across a half-used box of matches – surely an ideal enclosure for a covert spy transmitter!

Objectives:

1.    The matchbox should remain fully functional and pass casual inspection
2.    Transmitter, Morse key and battery should be hidden within the box
3.    All parts should be cobbled-together from what I can find around the house
4.    To build using “Manhattan style” construction for the first time

The transmitter borrows heavily from the Pixie 2 circuit and is based around two PN2222A transistors: the first forms a Colpitts oscillator for 7030kHz (plus/minus a smidgen of capacitor trim), the second acts as a modest Class C power amplifier (approximately 170mW out) – keying occurs here, to minimise chirp, before feeding a simple low-pass filter. 

Discrete contacts set in the cardboard allow Morse to be keyed with my grandmother’s old sewing thimble – not only is this beautifully stealthy but it’s remarkably ergonomic too!

The transmitter can be easily teamed with an external receiver, selectable via a double-pole-double-throw switch. The switch simultaneously disconnects the battery, eliminating the audible whistle from the constantly-running oscillator.

This was my first experiment with “Manhattan style” construction and I can see why you swear by it. Even though I sketched the circuit’s layout before I started, I still found myself occasionally popping-off a square with a blade so as to optimise the tight packaging; Manhattan made this trivial, and fault-finding would have been easy with all connections on one side…

But remarkably the transmitter worked first time! Bench testing by calling CQ whilst monitoring the Reverse Beacon Network demonstrated that its tiny signal could be picked up as far away as northern France when driving my resonant end-fed antenna!

Ever since I discovered the magic of QSL cards I have always wanted to send one showing a hand-drawn diagram of my transmitter; perhaps I’ll now have a chance!

Please keep up the great work: you, Pete and the global brotherhood never cease to throw up new tricks for me to try. It’s a shame that this is perhaps one radio which I’d be best advised to not try to carry through airport security when my ever-patient girlfriend grants me permission for a holiday-time QRP operation...

73

Jonathan

M0JGH

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

Earlier post about Jonathan: http://soldersmoke.blogspot.com/search?q=M0JGH

Update on Farhan's BITX 40 Module

It is truly a thing of beauty:  http://www.hfsigs.com/   

The boards come assembled (as seen above).  You can then add peripherals and modify away.  It is "hackable."

Hackable

The BITX40 will inspire you to experiment. Modify it, mount it, tweak it, change it.
The PCB uses all analog large sized SMD components that are laid out on an easy to understand manner on a double sided board with broad tracks. This can be your main module around which you can start experimenting. There are jump-points from where you can add more modules like the DDS, more bands, better audio amplifier, etc. Imagination is your limit. You can separately increase the power amplifier's supply voltage to 25 volts to be more than 20 watts of power : You will have to add a better heat sink. The mods are on the way!
The board can be installed inside any box that you like. Make your own station rigs, man-packs, trail radios or mount it in a cigar box and leave it on your bedside table. The tuning capacitor has been replaced by a varactor tuning so you can place the tuning knob anywhere as it only carries a DC voltage.

Farhan writes:

For the last few months we have been working bringing low cost, tested SSB boards. Finally they are here. Priced at Rs.2200 At the moment, they are available only in India until we sort out an inexpensive way to post them to other countries. Visit www.hfsigs.com and pick up one!

The BITX40v3 is a complete 7 MHz SSB transceiver on a board that puts out 5 watts of clean audio and it has a very crisp, all analog receiver. It is based on the popular BITX circuit. It is a high quality double side, PTH PCBs with machine assembled SMD components, hand wound coils and each of them is individually tested. All the connectors and wires needed are included in the kit.

JH8SST/7's Build of Pete's Simpleceiver

Beautiful. 

Makes me want to put S-meters in my rigs.

More on Pete's design here:

http://n6qw.blogspot.com/2015/09/simpleceiver-40m-ssbcw-receiver-and.html

In De Ether (Short Belgian documentary about ham radio)

In De Ether (English Subtitles) from Ivo Maes on Vimeo.

From the DSB-SSB Pier In Melbourne, Australia: SolderSmoke Book Reviewed by VK3YE

It is a real honor to have my book reviewed by DSB guru Peter Parker VK3YE, and to have him do the review from the iconic "DSB-SSB" pier in Melbourne, Australia.  Check out the video (above). Thanks Peter.

GW4ZUA's "Let's Build Something" Receiver

The LBS project of Pete and Ben continues to inspire homebrewers all around the world.  Check out the video of GW4ZUA's version.  Peter GW4ZUA writes:

Hi Pete,

Thank you for your kind words,

I suppose it started with a knob and a pointer to know (guess) where you were on the band, probably most radio builders did the same, and some still do, but as long as it worked you were very satisfied, what a marvelous feeling when you switch on and those electronic components do their job and deliver the goods......amazing.

So time moves on you get better at building and technology gives you a hand, LCD displays, homebrew frequency counters,cheap components, wow now you Know where you are on the band.

Then I saw your rig with a colour display and DDS "I gotta get me one of these."

I watched most of your videos, Your "easy going, down to earth manner" made it look easy to do.
I love the internet, without it I'd probably still be using knobs and pointers, there are is a wealth of knowledge available to those lucky enough to have access. I also love email, as you can now contact people who are willing to share their projects and give advice.

So the LBS well it certainly works, so few parts but they are all eager to please, with the display (did I mention the display) it is a project you can be proud of.

A big thank you to you and Ben for the project,

I don't know if it will ever go in a box as I just love to look at it and I'm amazed at what comes out of the speaker.

Regards to you all..........
73's for now.  ...........Peter (GW4ZUA)
------------------------

As is well known, I'm more of a knob and pointer guy myself, but I understand the attractions and advantages of the glowing numerals.  And I definitely sympathize with Peter's comment about the beauty of an in-boxed rig.

Listen to Keith Ranger G0KJK on "QSO Today"

http://www.qsotoday.com/podcasts/g0kjk

Wow Eric,

I just listened to all of the Keith Ranger interview and was struck by the eerie parallels between YOUR 24 September podcast and OUR 24 September SolderSmoke podcast:

-- Both shows discussed the involvement of Anglican clergy in the hobby.

-- Both discussed the joys of simple QRP gear.

-- George Dobbs G3RJV came up in both.

-- BOTH featured discussion of the BD139 transistor (!!!)

-- Both discussed the use of ceramic resonators in ham circuits.

Great minds think alike!

I really enjoyed your interview with Keith. I have enjoyed reading in SPRAT about his projects -- years ago I built his MB4 receiver. I listened while I worked on my homebrew receiver. It was the ideal accompaniment. I also like the stickers on his transmitter.

Please pass this on to Keith if you can.
Thanks and 73 Bill
---------------------

I also liked Keith's comments on the joys and perils of amateur electronic engineering. 

Video: Sweeping a Filter with a FeelTech Signal Generator and a Rigol Oscilloscope

This short video shows how I used my new FeelTech Signal Generator (90 bucks shipped from China) and my trusty Rigol oscilloscope to display the passband of the filter in my Armand HROish receiver.  Feedback on this test procedure would be appreciated.

K1RID's 6L6 CW Transmitter from QST: "Barracks Bag VFO"

A new old thermatron device is coming to life on the kitchen table of K1RID.  Don't spill the coffee on that thing Ed.

Blowing the Dust Off of KW4KD's Homebrew Station from the 1970s

KW4KD CW TRANSMITTER

I got on 40 meter SSB over the weekend and spoke to Jim KW4KD.   He was on a modern commercial rig, but then he told me he had some homebrew gear on his shelf...  Wow, it is magnificent.  A complete CW station (with homebrew keyer) AND an SSB rig. I immediately launched a campaign to get Jim to fire that gear up and to provide opportunities for more HB2HB contacts.   Here is his description of the equipment:

Hi Bill,

It was a blast to get to chat with you too.

Just listening to the audio on this end, I can tell you’ve put a lot of time and effort into getting what you have there up and running.

Never once touched the dial on this end. So your radio gets a A+ for stability too.

Read your Bio on QRZ and sounds like you’ve been a few places, and seen a few things, and that unto itself would make a great contact . But for me, the fact that you are out there building, and I ‘m getting to hear the fruits of your efforts, is ham radio at its best.

 

Attached are pictures of the gear that made up my station back in the 70’s.

FWIW: At that time my call was WB4YQC.

(But for the record, these shots were taken today.)

In those days I had two setups (Both on 40 mtrs).

A CW station, using separate Xmtr & Rcvr, And a SSB xcvr.

By themselves the CW xmtr ran 8 to 10 watts, and the SSB unit probably hit 5 Watts peak (on a good day).

Like you, I had a separate linear. But in my case I used a pair of 6DQ5’s (TV Sweep tubes) that would run about 180 watts input, (Nothing Solid State, that I could afford, could make that kind of power back in then). The linear is still here, but stashed away in a closet somewhere, so not shown in today’s set of pictures.

As an Add-On for the SSB unit, I built a Frequency Counter, and used it as a digital dial.

The counter is unique in that it supports two inputs (one for the VFO, and the other for the Xtal BFO). In the 2 input mode, the counter is an UP/Down counter.

The Xcvr’s BFO runs at 9Mhz, while the VFO runs at ~2Mhz. So the counter counts up on one pass, and then down on the 2nd. At the end of the 2nd pass, it updates the Display with the final tally. (i.e, the effective TX/RX freq)

The cases for the Xmtr & Xcvr were designed by me, but were built by a friend who had access to a metal brake. Internally none of the units are especially pretty, as the were always works in progress.

I’ll have to dust off the linear. Its been at least 40 yrs since its seen AC.. Not sure what kind of shape the electrolytics are in.

Probably need to apply power slowly. I’ll see if I can round up an Autotransformer.

As far as posting on your blog, if you think it will encourage others, I’d be flattered if you did;

However, before anybody asks, (assuming that they might) there’re no schematics. Everything was built from sketches made on envelopes and napkins, which have long since disappeared. And even if they did exist, not sure today that you’d be able to find some of the ICs & transistors that the units use.

Again, it was my pleasure to catch you on the band today, & look forward to getting to hear you again.

73  Jim (KW4KD)

KW4KD CW TRANSMITTER WITH HB KEYER

40 Meter CW receiver on Left

40 meter SSB transceiver with freq counter

Video of Armand HROish Receiver

SolderSmoke Podcast #190: Pilgrims, Junkbox rigs, BANDSWEEP, Matching xformers, On the Air with HB, MAILBAG

SolderSmoke Podcast #190 is available:

http://soldersmoke.com/soldersmoke190.mp3

Pilgrims' Progress:  Inspiring words from G3RJV

BENCH REPORTS on JUNKBOX RIGS:

Pete describes his beautiful 40 meter blue transceiver (video above)

Bill describes his "Armand HROish" receiver

BANDSWEEP!

Bill needs small (yellow slug) 455 kc transformers.

We need a good user-friendly 40673 SPICE model.

SEND US YOUR BENCH REPORTS!

The BD139 transistor

Ferrite Core Matching Transformers

QSO Reports:  Getting on the air with HB rigs

Bill's new FeelTech Signal Generator

MAILBAG

QRPp Back Issues (and some new ones too!)

Here's an index: 

http://www.k7qo.net/qrpp_toc_de_k7qo.pdf

And here are lot of the back issues:

http://www.ncqrpp.org/

And I see there are August and September 2016 editions available in the Files section (KI6DS)  of the qrp-tech Yahoo group.  Did I see articles there from Steve "Snort Rosin" Smith?

My New Chinese Signal Generator

More amazing low-cost test gear from China.  Elisa gave me this device on the occasion of my completing another solar orbit.  Amazing capability for less than $90.  The video above gives you a good sense of what this thing can do.

I have already had success with the freq generator function.  The frequency counter also works great.  The sweep function looks very useful for filter checking.  And the ability to generate square waves at different phase relationships will be very useful in phasing receiver and transmitter projects.  

This little box should help me eliminate a lot of clutter on the work bench.  And it looks good next to the Rigol 'scope.  

Mine came from Amazon:

https://www.amazon.com/gp/product/B01A8S4TZK/ref=oh_aui_detailpage_o00_s02?ie=UTF8&psc=1

They come with a variety of different brand names:  I ordered a Jinwen but got a FeelTech.  They are obviously the same device.

Be sure to begin your Amazon shopping on the Amazon search link on the SolderSmoke blog (upper right).

QRP Wisdom from George Dobbs, G3RJV

This video makes me want to destroy my amplifier...

Alan Wolke Talks 'scopes on "The Workbench" Podcast

George KJ6VU is a long-time supporter of the SolderSmoke podcast.  He has recently teamed up with another ham and launched a podcast called "The Workbench."  This morning I listened to Part I of their interview with the legendary Alan Wolke W2AEW.   It was great.  As I was listening to Alan I was soldering together a crystal filter for my new receiver, and using my RIGOL 'scope to check the results.  

I liked Alan's description of how they made images of 'scope patterns in the days before the advent of Digital Storage Scopes (Polaroid!).  I also liked Alan's scorn for those who use the "Auto" switch on the 'scopes.  The host's reaction to Alan's description of a $300,000 Tektronix 'scope was also fun: "For that price I want to be able to drive a car into it and put a swing set behind it!"  Indeed.

Recommended listening:   
http://hamradio360.com/index.php/2016/08/30/ham-radio-workbench-5-oscilloscopes-part-1/

Oz JOO : An Australian Mighty Mite with 3D Printing

Hi Bill & Pete,

I have the JOO - joy of oscillation! The transistor is a 2N3053 with a clip on heat sink, but I don't think that I really need it. Output power +22dBm or 160mW. When I tested it on a Comms test set  at work, I found that the harmonics were about 12dB to 15dB down and I stopped looking at the 10th harmonic. Not good.

Fitting the 80m low pass filter (salvaged from another project) brought the harmonics more than 50dB down.

The coil former is a 31mm diameter and 3D printed by one of the guys at work. The material is PET - the material they make soft drink bottles from. After we printed it, I put it in a microwave oven with a glass of water. 30 seconds and the water got warm and the coil former stayed cool.

I haven't had a contact yet, but maybe in the next few weeks.

The next project is an 80m CW transmitter based upon the Goodfeller transmitter from QST 1946. It requires a inductor in the pi coupler, 1.5 inch diameter, 32 turns at 20 tip; but where to get one of those these days - wind your own.

I got the guy at work to also 3D print me a coil former with a spiral thread around the outside with a 20tpi pitch for the wire to lay in. Some hot glue and the coil is ready.

Now that I have finished all 189 episodes and two specials, my days are empty. Please make some more.

73 de Peter VK2EMU

Hi Peter (great name BTW),

 

Congratulations –really liked your build – top drawer! 3D printer access WOW – now if I could only get my 3rd son (Mechanical Engineer) to build me one of those machines.

 

The 3D made coil form is perfect for a VFO and follows the principles set down by Doug DeMaw W1FB (SK) about keeping the coil supported at both ends and away from metal. Bill needs a coil like that to mate with his HRO dial mechanism –and follows something old (dial) something new (coil).

 

73’s

Pete N6QW

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! 

First Signals from the "Armand HROish" Receiver

I've been kind of busy lately with other things, but I have managed to squeeze in a few minutes most days to work on my latest receiver project.  I call it the Armand HROish receiver.  Armand WA1UQO sent me the big National HRO-style dial and gear box, and he was there at the Manassas hamfest when I bought the dual variable cap that now serves in the front end pre-selector.

I went with a 455 kHz IF.   The idea is to have a receiver that tunes from around 6.5 MHz to around 8 MHz so I can do some shortwave listening AND listen to 40 meters.

So far the filter consists of three IF cans (one small transistor can and two larger tube-type cans).  The small transistor can was given to me by Michael Rainey AA1TJ - thanks Mike. Doug DeMaw suggested this use of IF transformers in his "Design Notebook."

At the front end I have a tunable dual tuned circuit filter followed by a 40673 amp. 

The mixer is an SBL-1.

1st and 2nd IF amps are a 23 db 50 ohm termination insensitive amplifiers.

I have a second SBL-1 that will be the product detector, but I haven't built the BFO yet.  So today I hooked up two 1N34A diodes in voltage double config and -- with a bit of AF amplification, got the receiver inhaling with a diode detector.   I could pick up Radio Canada.  Then I heard SSB sigs on 40.  With no BFO, I decided to put my sig gen on 455 kHz and just wrap the lead around the IF cans.  It worked -- I could listen to SSB and CW sigs.  Very satisfying. 

Still to do:

-- BFO and product detector.

-- Work on AF amp.

-- Get my CM-455 crystal mechanical amp in there with some relays around it so I can switch from narrow to broad via the front panel.

Lots of soul in this receiver:  All parts either 1) came out of the junkbox, 2) were gifts from friends, or 3) were recent hamfest purchases.  The HRO dial from Armand and the IF can from AA1TJ.  The 455 kHz filter idea came from Doug DeMaw, the VFO circuit from SSDRA.  The VFO base is from Whole Foods and the whole thing is built on a kitchen cutting board. It includes a 40673 and germanium diodes. The VFO amps are in Altoid tins.  It will, when finished, go into a big metal box given  to me by Tim KI6BGE and shipped east by Pete Juliano.  And when I was working on the 1st mixer, I accidentally pricked my finger and a drop of N2CQR blood went onto the breadboard.  Of course, I left it there.   SOUL!

The Radio Gods are apparently pleased:  In the first hour or so of listening, I was rewarded for my efforts when I managed to hear Tim WA1HLR on 40 AM describe his troubleshooting of an old piece of gear.  TRGHS.  

A Signal for SETI? HD 164595

That's the Russian radio-telescope that picked up what was thought to be a possible signal from an extraterrestrial civilization.   This article from the SETI Institute has some interesting tech info on antennas and power levels.  Definitely not QRP!

http://www.seti.org/seti-institute/a-seti-signal