Honorable Mention: Bruce KC1FSZ's SolderSmoke Direct Conversion Receiver ON A PRINTED CIRCUIT BOARD

This is obviously not the style of construction that we would recommend for new builders.  Thus the "Honorable Mention" category.  But Bruce is not a new builder -- in fact he has been a friend of the SolderSmoke podcast for many years: https://soldersmoke.blogspot.com/search?q=KC1FSZ   When Bruce sent us the above video and a report on his build of the SolderSmoke Direct Conversion Receiver,  we thought it was so cool that we wanted to share it with the community. Be sure to go to Bruce's GitHub page for more details: https://github.com/brucemack/kc1fsz-tjdcr

Bruce writes: My unauthorized modification is in the construction realm.  I've built Bill/Dean's original circuit in a compact form on a commercial PCB. This was a good chance to practice with KiCad, Chinese PCB fabs, and SMD soldering. Huge thanks to Scott KQ4AOP for making me the PTO form! The rig works great.  Thanks to Bill/Dean for leading such a successful/educational build project.

Hi Bill:

I had refrained from any postings of my work because the "purity" of my build may be called into question and I didn't want to create further distractions from your efforts. HIHI.  If you scroll down this page you'll get an idea of what I've been up to: https://github.com/brucemack/kc1fsz-tjdcr.

I also see that you've switched away from the Schottky diodes which I have not done, so I'll make that change to see how it impacts performance.

Moving fully into the realm of unauthorized deviations, I've been experimenting with the simple "frequency offset" feature shown in SSDRA on page 218. Hanging that simple circuit from the high side of C2 seems to provide the hook needed for a simple companion CW transmitter module. Joking aside, I'd never built an analog VFO before the TJDRC project, nor did I ever learn CW, so it's been quite interesting to try to create a sister board that stays true to the TJDCR ethos but can still make legit contacts.

Thanks for all the work you guys are doing to educate the rest of us,

Bruce KC1FSZ

Dean and Bill:

What you guys have done with this project is truly amazing. I didn't build the rig in the "original wave," but I recently made one just for fun.  I finally got around to looking at your Discord this weekend and was completely amazed...  And Dean's tutorial videos are surely headed for YouTube platinum status!

Congrats and 73s,

Bruce MacKinnon KC1FSZ, Wellesley, MA

Bruce:  There are several builders on Discord who would be very interested in your CW transmitter module. 

Thanks Bruce!  Congratulations!  73  Bill  Hi7/N2CQR

SolderSmoke Podcast #240 NIMCELS? Hex DX, CBLA RX, PTO? Solid State HT-37? Exotic caps, Benches, SBE-33, TenTec 540, KWM-1 MAILBAG

 

SolderSmoke #240 

Monday September 19, 2022

http://soldersmoke.com/soldersmoke240.mp3

Sorry, I had some technical difficulties so my audio is a bit distorted. 

NIMCELS?  Niche Internet Micro Celebrities. I dunno....  Can our listeners come up with an acronym that describes our place in the universe?  

Sponsors:  Parts Candy.  Carlos in Chicago.  Great leads.  Don't scrimp with a crimp!  You need some good quality test leads on your workbench.   Get yours from Carlos.  Click on the picture on the blog page or go to PartsCandy on e-bay.  

"Techno Wizardry"?   Our lawyers at Dewey Cheatham and Howe will be after them for that!  

Bill's Bench: 

Hex Beam has made me a DXer.  91 countries. Having fun. Mozambique (Long path), San Andres island, and Saudi Arabia, all on Friday. All homebrew SSB 100 watts. 

Put my old 20 meter CW station back on the air:  Barebones superhet and the VXO 6 watter.   WYKSYCDS. This may be one of very few CBLA Receivers in the world!

Been getting active in the Vienna Wireless Society.  Dean KK4DAS is President and a lot is happening in the Club.  Makers group. Lunch with the group on Tuesdays.  Lots of fun.

We are looking at Farhan’s Daylight Again Analog rig.  Using parts from Dean’s 3D printer, we have made PTOs. See blog post for picture.   (But are they really PTOs? Or just Variable Inductors?) 

VFO madness.  Solid stating an HT-37 VFO. Grayson: “You have clearly lost your mind.” Perhaps.  100 MHz FM broadcast RFI. This brought me to capacitors and linear tuning:

SLC, SLW, SLF and Midline/Centerline caps.  Do special caps explain why some VFOs have linear tuning while others do not?  NO, not really.  You can get linear tuning with ordinary caps.  See blog post

Working on the bench.  Reading Adam Savage’s book on workshops and tools. (link to the book in the right hand column of the blog.   Some other workbench links on the blog.  Upgrading tools and test gear.  I have a proper bench power supply. Better side cutters.  Engineering rulers.  Digital calipers. Better solder (I was talking to Ron WA6YOU – a real solder authority - about this.  Kester 60/40 ).

SHAMELESS COMMERCE DIVISION: 

mostlydiyrf.com

Currently offering seven items:

·  UDVBM-1 (in three versions)

·  PG-TIA Broadband IF Amplifier

·  TIA-AGC IF Amplifier

·  Dual-Gate MOSFETs

·  OA741D Op-Amp (discrete components)

·  8-Pole QER Crystal Filter

·  I2C Rotary Encoder

Three more are shown as coming soon:

·  GP Audio Amp (general-purpose audio amp)

·  HyCas IF Amplifier with AGC

·  M-Cubed (Michigan Mighty Mite kit)

·         Mostly DIY RF offers hardware for hardware-defined radio. That's not a comment on software-defined radio. SDR is cool and useful, and it has its place.

·         In fact, I believe in explicitly making use of technology from all eras (vacuum tubes, discrete semiconductors, and integrated circuits

·         What does "mostly" DIY mean? It means making what you want and using ready-made for the rest. Even the most fanatic DIY'ing home brewer does this without much thought. He uses components he didn't fabricate, electricity he didn't generate, and theoretical knowledge he didn't discover. One can't fight all battles, one has to choose which to fight and which to leave to others. If an appliance-operating Ham doesn't want to fight at all, that's okay, but Mostly DIY RF has nothing to offer him.

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

I need YouTube viewing hours.  So I am putting some of the best SolderSmoke podcasts up on the YouTube channel.  Please listen/watch on YouTube. Here is the playlist:  https://www.youtube.com/playlist?list=PLv9MEKq1quk-gnxog7eBqY_y7cpQadf6T   

Google feed no longer sending our e-mails.  So please follow the blog, Get yourself a blog feed reader.  I use Feedly.  It is free.   Download, search in Feedly for SolderSmoke, hit subscribe and you are done. https://feedly.com/i/discover Follow Pete’s blog too!  It is easy.

 Pete’s Bench

Resurrections: 

SBE-33!

TenTEC Model 540

KWM-1

Mailbag:

Dan KC5VPI getting into homebrewing. No longer WRONG!

Michael AG5VG built subharmonic DC receiver, put it on 40 and 20.  FB.

Mike AA9IL working on old tube stuff including a DX-100 AMD UUHF gear up to 122GHz.

Ed WA4MZS liked the SolderSmoke book. USCG vet.  As is Mike Rainey AA1TJ Semper Paratus!

Clint KA7OEI – The Music of the Beams – My Hex  does not sing!  So far!

Walter KA4KXX – The Knack started early.  Video of getting a toolbox for Christmas. And working on PTOs!  He likes them!

Phillip G4HOJ Also working with subharmonic mixers – using the more complex 4 diode version.

Peter GW4ZUA Built an amazing rig from RADCOM (1980s) Cool VFO with varactor fine tuning and a coil with a dust core that was cut in half to minimize temp effect. Box now holds 3  band version of Pete’s SimpleCeiver. FB.

Bruce KC1FSZ building 25 Watt amp for his Peppermint Bark rigs.  We won’t turn him in to the QRP authorities.

Grayson KJ7UM tested the 12BY7A from my DX-100 VFO.  It was in fact weak. Thanks Grayson.

Charles Smith KV4JT has some really interesting stuff on how to solid state tube gear.   Especially R-390s. https://soldersmoke.blogspot.com/2022/08/trigger-warning-solid-stating-old-tube.html

Gianfranco I0ZY Old friend from Rome.  Amplifier manufacturer.  FB.

Paul WA1MAC getting started again after long hiatus.

Vasily.. I mean Todd VE7BPO.  Always great tech info.  Thanks.

Mark WB8YMV building a superhet with a 455 kc IF.

I sent Farhan some comments on his Daylight Again video: He wrote back “I marvel at their stamina to watch an hour long video of a man talking with a funny accent!”  

Video of SolderSmoke Podcast #235

Pete and Bill in LIVING COLOR! 

SolderSmoke Podcast #235 is available for download: 

http://soldersmoke.com/soldersmoke235.mp3

Travelogue:

6 weeks in the DR for Bill
One contact on uBITX. More SW listening.
Repaired my Chrome Book in Santo Domingo!
Christmas Present for All: James Web Space Telescope launch

Bill's Bench

-- Understanding the NE-602 (see blog post)

-- Thinking about a 17/12 dual bander.  Looked at old G3YCC Tx for circuits... 

-- Using Spurtune08. WB9KZY found it.  In the LADPAC zip file here:

https://web.archive.org/web/20091222012628/http://w7zoi.net/emlad08_123.html

-- Then Put G3YCC Acores SSB TX back in operation

-- Put W4OP Barebones Superhet on 17 with NE602 down converter.

-- Netting and audible spur problems 

-- Now working many stations with this old "split" TX/RX

Pete's Bench

-- The Peashooter

-- Dean's VWS build of your DC RX

-- Building a SSB Transceiver Doc

-- Homebrew Crystal Filters

-- The shrinking of the PSSST

-- PSSST on Hack-A-Day

Bad Dead Soldering Stations

-- My X-Tonics 4000 dies.   But it left behind a great box with ample socketry. 

Mailbag: 

AA1TJ Mike Rainey --- Again in the Hobbit Hole! 486 kc RX

Thomas K4SWL -- Radio Astronomy and the Raspberry PI 

WC8C Dennis Invite to the L'Anse Creuse ARC   FB  Fun

Todd K7TFC got boosted at Tektronix Beaverton Ore.  

What happened to Chuck Adams K7QO?  His work taken off the net.

W1MJA ex WN2RTH 

N7DA worked W7ZOI in Sweepstakes.  FB

Kirk NT0Z formerly of ARRL HQ

Farhan VU2ESE was up in the Pench Forest, trying to spot a Tiger! 

We spoke to Farhan's Lamakaan ARC in Hyderabad.  QO-100 beam down! 

Dean KK4DAS's 16 watter.   On SS blog

Scott WA9WFA  Bad 6U8s?   Ordering 6EA8s

Bruce KC1FSZ Peppermint Bark gift box

Mike WU2D:  Book by Frank Harris on Homebrew radio

Bob Scott KD4EBM So many good ideas and links 

Rogier PA1ZZ sending parts packages -- Thanks Rogier

SolderSmoke Podcast #235 NE-602, Azores Rig, Spur Problems, SSB Rigs, Peashooter, HB Filters, MAILBAG

SolderSmoke Podcast #235 is available for download: 

http://soldersmoke.com/soldersmoke235.mp3

Travelogue:

6 weeks in the DR for Bill
One contact on uBITX. More SW listening.
Repaired my Chrome Book in Santo Domingo!
Christmas Present for All: James Web Space Telescope launch

Bill's Bench

-- Understanding the NE-602 (see blog post)

-- Thinking about a 17/12 dual bander.  Looked at old G3YCC Tx for circuits... 

-- Using Spurtune08. WB9KZY found it.  In the LADPAC zip file here:

https://web.archive.org/web/20091222012628/http://w7zoi.net/emlad08_123.html

-- Then Put G3YCC Acores SSB TX back in operation

-- Put W4OP Barebones Superhet on 17 with NE602 down converter.

-- Netting and audible spur problems 

-- Now working many stations with this old "split" TX/RX

Pete's Bench

-- The Peashooter

-- Dean's VWS build of your DC RX

-- Building a SSB Transceiver Doc

-- Homebrew Crystal Filters

-- The shrinking of the PSSST

-- PSSST on Hack-A-Day

Bad Dead Soldering Stations

-- My X-Tonics 4000 dies.   But it left behind a great box with ample socketry. 

Mailbag: 

AA1TJ Mike Rainey --- Again in the Hobbit Hole! 486 kc RX

Thomas K4SWL -- Radio Astronomy and the Raspberry PI 

WC8C Dennis Invite to the L'Anse Creuse ARC   FB  Fun

Todd K7TFC got boosted at Tektronix Beaverton Ore.  

What happened to Chuck Adams K7QO?  His work taken off the net.

W1MJA ex WN2RTH 

N7DA worked W7ZOI in Sweepstakes.  FB

Kirk NT0Z formerly of ARRL HQ

Farhan VU2ESE was up in the Pench Forest, trying to spot a Tiger! 

We spoke to Farhan's Lamakaan ARC in Hyderabad.  QO-100 beam down! 

Dean KK4DAS's 16 watter.   On SS blog

Scott WA9WFA  Bad 6U8s?   Ordering 6EA8s

Bruce KC1FSZ Peppermint Bark gift box

Mike WU2D:  Book by Frank Harris on Homebrew radio

Bob Scott KD4EBM So many good ideas and links 

Rogier PA1ZZ sending parts packages -- Thanks Rogier

SolderSmoke Podcast #222 Antennas, Phasing, VFOs, 2-Bs, 6 years of N6QW, MAILBAG

After 46 years, finally a dial skirt

SolderSmoke Podcast #222 is available:  

http://soldersmoke.com/soldersmoke222.mp3

No travelogue but… SolderSmoke Almanac!

Memorial Day in U.S.

End of Ramadan so Eid Mubarak! 

#222 marks SIX YEARS of Julian-ismo.  He started on SS 161.  Thanks Pete. 

Thanks to all who sent good wishes on Billy's graduation.  He heads to Boston and the lab in a week or so.  Very proud. 

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

Bill was on Ham Radio WorkBench Podcast  

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

PETE'S WORKBENCH

-- Antenna Ideas -- Don't Buy that $165 dollar dipole!  It is just wire!   

-- THE PHASING RIG. Does this point to a need for meditation?  Or at least some temporary disengagement? Tribal wisdom from Pete. 

-- DEAN KK4DAS's rig.  The Furlough 40.  Troubleshoot.  Tribal knowledge. 

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

-- SHAMELESS COMMERCE DIVISION:   AMAZON BOX -- SEARCH FOR ANYTHING OU WANT THERE.  

-- PLEASE PUT COMMENTS ON THE SOLDERSMOKE BLOG POSTS. 

-- PLEASE CHECK OUT THE SolderSmoke YOUTUBE VIDEOS. 

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

BILL's WORKBENCH

n  Shortwave dials and exotic locations.  Java!  

n  Galaxy V VFO Project. Series-tuned Colpitts.  

n  DRAKE 2-B.  Hayseed Recap. Put the skirt back on the old rig.  Reduction drives?   

SHOPPING BAG: 

I got a replacement for the Xtronics 4000 soldering station.  Yaogong worked! 

https://www.amazon.com/gp/product/B078WB9Z2R/ref=ppx_yo_dt_b_asin_title_o02_s01?ie=UTF8&psc=1  

Ordered screws and stuff from McMaster -- Came very fast! 

Working on a resistor kit from Mouser. 

MAILBAG: 

VK2BLQ's Phasing RX with an HRO dial.  Cool Retro.  

Adam N0ZIB -- Cool station.  TFT screen Aluminum welded box. FB. 

Karl G7AFT    BITX 40 doing USB and LSB by changing the VFO freq.  Pete's trick! 

Jerry KI4IO  out in nearby Warrenton.   Hope to be able to meet up soon. 

Keith N6ORS's Hot Mustard Phasing Board. 

Mike N5GTF'd FULLY INDOOR Quarantine Receiver.  Need a slogan for the antenna!

Nick M0NTV's Bread Bin 80 Quarantine rig

Bruce KC1FSZ   Quarantine 10 -- Brave man in solar minimum. But I hear 10 is opening.

Talking to Grayson Evans KJ7UM  TA2ZGE about Collins 9.9 MHz transformers.

Talking to Alan Wolke W2AEW about Drake 2-B stuff  Was there a reduction drive?

Paul VK3HN about Ceramic filter spurs.

Peter VK2EMU notes no animals were harmed in the making of my videos.  But many electrons were agitated. 

N6QW Phase Shift Success -- It aint over 'till the fat lady sings

10 Meter Quarantine QSOs near Boston -- KC1FSZ's Peppermint 10

Hi Guys:

I hope all is well.  Thanks for the more frequent episodes!

I’ve not submitted anything lately but I’m still doing a lot of building.  Over the last few weeks I’ve been working to get myself on 10 meters.  There is some good local activity up here in the Boston suburbs on 10.  The result of this effort is the next in the Peppermint Line of high-performance radio products for the discerning operator: The Peppermint 10.  This rig uses digital VFOs and puts out about 12 watts on a good day.  It works in conjunction with a direct-conversion receiver that has been modified for 10 meters.  The details are described in the write-up (see link):

https://mackinnon-public-web.s3.amazonaws.com/peppermint-10/index.html 

73s,

Bruce KC1FSZ

SolderSmoke Podcast #209 SKN, Old Rigs, Movie Review, Safety Tips, Mail Bag

SolderSmoke Podcast #209 is Available: 

13 January 2019

http://soldersmoke.com/soldersmoke209.mp3

An HT-37 "With Presence!"  Even on CW!  A Straight Key Night Story
Saving a much-loved HT-37 
Drake 2-B Alignment
Tweaking the Mate for the Mighty Midget
Fixing a Deaf DC Receiver
A Wobbly National HRO-ish Gear Box 
Minimum Discernible Signal Tests
Pete's Festive Holiday Transceiver in a Bottle

Movie Review:  "First Man"  Neil Armstrong goes to the moon. 

Safety Tips for 2019:  Fuses, Hard Drives, Flu Shots. 

MAILBAG: 
Dave G6AJW builds Pete's Sudden Transceiver
Rogier KJ6ETL builds a new shack
Steve N8NM Helps save the HT-37
Jim AL7RV W8NSA builds Parasets
Dave AA7EE puts a beacon on the air -- Please Listen! 
Jan OM2ATC builds and documents an Si5351 VFO
Bruce KC1FSZ Homebrew's a BITX
KB1GMX's Tip on IRF-510 Oscillation Prevention
Ryan W7RLF Homebrews a DC Receiver

Listening to August K5HCT from the East and West Coasts on 40
Tim WA1HLR rebuilding his 1968 transmitter.  

KC1FSZ's Peppermint III Homebrew BITX with Mods

Hi Guys:

I had some time over the holiday to finish off my second scratch-built rig.  I am very thankful that I got the work done on these projects before I read Pete's "Don't Build It" diatribe.  That would have been very demoralizing. :-)

Scratch build #2 (called Peppermint III) is still fundamentally BITX although I've made changes this time around.   I've switched to ADE-1 mixers with LO ports driven by adjustable gain buffers (ala N6QW LBS).  I've noticed that performance can be improved a lot if you can buffer/tweak the LO levels of the VFO and BFO (particularly carrier suppression on TX).  I did W7ZOI TIAs in the IF chain.  I've also taken the shielding/layout of the finals more seriously and have been able to dial up the power a lot (I did the KB1GMX thing with cutting off the drain pin on the IRF510 and using the tab).  The software is also greatly improved and now supports LSB/USB modes as well as software-driven PTT control for RTTY/FT8 and the hooks for my poor man's panadaptor.  I've been working lots of stations on QRO.

Total build time was about three months (half the time of #1) and the layout came out much smaller than before.  I made a trip over to Williams/Sonoma after Christmas and picked up the 2018 edition of the Peppermint Bark candy tin on discount and I think I can make it all fit.  More to follow ...

Happy New Year and 73s,

Bruce KC1FSZ

SolderSmoke #205 Solstice, Mars, Antennas, Displays, Phasing Fix, VFOs, Lexicon, MAILBAG

June 23, 2018

SolderSmoke Podcast #205 is available:  

http://soldersmoke.com/soldersmoke205.mp3

-- Summer solstice.  Mars Observations.  Graduations.  Internships.  Fathers Day.

-- Antenna Angst:  Pete's tribander and Bill's Moxon.  Insulation and resonance?

-- Pete's work on color displays. 

-- Bill goes back to fix up older projects:  

-- Fixing the Frankenstein Phasing RX.  Found an open choke!

-- Tightening up the HRO Dial. 

-- Achieving Juliano Criteria stability on a BITX20 VFO. 

-- Lexicon additions:  "Scratch Built"  "Hardrock Radio"  

https://english.stackexchange.com/questions/39551/where-does-the-saying-made-from-scratch-originate

-- PastaPete:  http://www.pastapete.com/

MAILBAG: 
Bob Crane W8SX Corrspondent at FDIM
Ralph AB1OP  Building LBS
Bruce KC1FSZ  Digital Pot
Jason W5IPA uBITX in Juliano Blue
Rogier KJ6ETL  ON THE AIR WITH A uBITX
Special thanks to Tim Walford for 25 years of Hot Iron.  

Digital Pot

No, this is not some on-line mail order thing.  Bruce KC1FSZ has done something that I find both amazing and horrifying:  he using a "digital potentiometer"  as the AF gain control in his BITX.  Remember when pots were simple and pure, when they were just a metal wiper that ran across a crescent of carbon of increasing resistance?  Well, those happy days are apparently behind us my friends.   What now?  Will we have endless discussions about where to find the driver for the 10k pot?   Will Facebook or Amazon or Microsoft secretly seize control of the data on our AF gain, perhaps to sell us hearing aids?   But enough of my ludism.  Good going Bruce.  AGC beckons. 

Hi:

I've built a few BITX rigs from scratch now and I'm starting to move to a modular approach using fabricated PCBs to make it easier/faster to build/mix/match the stages.  My audio amplifier module is based on the LM386.  I know others have moved away from this chip, but it still works for me.

I've added one feature to my audio amp stage that opens up some good possibilities.  Instead of the traditional potentiometer between the AF preamp and the LM386, I've inserted a digital potentiometer (MCP4131-103) that is controlled by three extra pins on the microcontroller.  The digital pot lists for $0.81 on Mouser so it's no more expensive than a physical pot and it's way more versatile.

Why do this?

• The module is quick to make if you're building a lot of rigs.
• AF gain can be controlled via the CAT port.
• AGC control can be done in software.  This enables all kinds of fancy AGC "attack" and "release" controls that can be seen in the docs for commercial rigs.
• This is an enabling feature for remote ops, which is why I did this in the first place.
• AF gain can be controlled using the same encoder (different mode) as is used to control frequency, etc. if you wanted to build a more compact rig.

The board is shown below.  This is one of my first forays into KiCAD/PCBs/etc. so it's probably not as "tight" as it could be.  Also, I'm using through-hole components so it's old-school building.  But the board only costs $7 on OSHPark and it's pretty quick to wire up.  Anyone who wants to order one from them drop me a line and I'll send you the link.

Schematic below.

73s,
Bruce KC1FSZ

Another Wood Box BITX! KC1FSZ Abandons Al-Fresco but Continues with Wood

'Tis a thing of beauty.   I like the wood.  And I like the hood.  The handles are a nice touch.  A fitting follow-up to its al fresco organic origins.  

Hi Guys:

I know there was a view that my giant BITX was supposed to be left out in the open, but I’m going to try to attend my local club’s Field Day festivities this year and the 4 foot long “planker” was pressing the limits of portability.  So I moved from the shack to the wood shop and built myself some custom cabinetry.  I think it looks a bit like an IC-73000 now don’t you think?  OK, maybe not.  

There is a hinged door at the top and shelf levels inside for the different parts of the circuit. The power supply and PA section are mounted on the bottom which can be removed for accessibility/serviceability.   The whole thing weighs about 10 pounds!!

73s,

Bruce KC1FSZ