Podcasting since 2005! Listen to Latest SolderSmoke
Monday, February 12, 2024
Dean's Amazing Homebrew sBITX
Sunday, December 17, 2023
Make Your Own SDR Software! And, "Analog Man" by Joe Walsh of the Eagles (WB6ACU)
Friday, September 15, 2023
HB2HB -- A Contact with Denny VU2DGR (video)
At first I didn't realize it was Denny. On September 11, 2023 at about 2330Z I had walked back into the shack after dinner. I think DX spots showed an Indian station on 20 meter SSB. Without realizing who it was, I tuned him in on my Mythbuster rig, heard the other station sign off, and quickly threw in my call. Denny came back to me right away, and I think both of us then realized that we recognized the call of the other station. Wow, it was Denny, VU2DGR, the Wizard of Kerala! At the time of the QSO, I didn't have my phone with me; after we spoke, I went to get it, so the video above captures part of Denny's subsequent contact. (You can also at one point hear Guapo barking.)
Denny has been running a wonderful station that combines SDR gear with and HDR tube type amplifier and a homebrew Moxon.
Here is Denny's station. The transceiver is a RadioBerry. the amplifier and power supply are on the other table.
Tuesday, August 15, 2023
The Wizard of Kerala (India) -- Denny VU2DGR -- SDR and HDR
Saturday, May 27, 2023
Hans Summers G0UPL and his new QMX: The Bob Crane W8SX FDIM Interviews Part 1 (audio)
We are very pleased and grateful to present this year's series of Four Days in May interviews by our FDIM correspondent Bob Crane W8SX. Once again Bob did an outstanding job interviewing the FDIM participants.
In this interview, the amazing Hans Summers talks about his latest QRP Labs kit, the QMX. It is a combination of the QCX Mini and the QDX.
Hans explains the M: QMX. The M is for Marriage. Magnificent. Merger. Marvelous, many things like that. It’s what you get when you marry the mechanical and conceptual design of QCX-mini, with the SDR, multi-band digital implementation of QDX. Simply: QDX + QCX-mini = QMX.
It has a very clever switching power supply that automatically adjust to prevent spurs and harmonics from the power supply from appearing in the band of interest.
I was especially interested in his plans to implement an SSB option in future software updates. Hans will use the same very complicated SSB generation scheme used in the trueSDX rig, but hopes to achieve higher performance and improved signal quality due to the much more robust hardware of the QMX.
Here is the interview:
http://soldersmoke.com/G0UPL23.mp3
Here is the QRP Labs site about the QMX: http://qrp-labs.com/qmx.html
Here is the QRP Labs web site: http://qrp-labs.com/
And here is a really wonderful and very current article by Hans on the evolution of QRP Labs and its rigs from 2010 right on up through 2023 and the QMX. It is really interesting:
http://qrp-labs.com/images/qmx/docs/fdim2023.pdf
Thanks to Bob Crane W8SX, Hans Summers G0UPL, and all of the FDIM organizers.
Wednesday, April 12, 2023
Farhan's sBITX -- Taking Orders! (Video)
It is really looking great. Congratulations to Farhan for bringing yet another amazing rig to the amateur radio community.
Order yours here:
https://www.hfsignals.com/Thursday, November 17, 2022
SDR Direct Sampling: The End of Homebrewing (as we know it)
I sometimes hear hams claim that our efforts to build simple direct conversion receivers are "very relevant" to modern technology and are "directly applicable" to today's communications techniques. These hams will say that direct conversion receivers are at the heart of modern rigs.
That's a nice thought, and it might have been true in the past, but I don't think it is true anymore.
I think the future is what you see written on the black box (!) that encloses the receiver in the above video: "DIRECT SAMPLING RECEIVER." In the recent past we did have two direct conversion receivers in the front end of SDR receiving systems. These receivers produced I and Q signals that were fed into the computer (often via the sound card). That was nice.
But the writing has been on the wall for a long time. There is no longer a need for all that direct conversion and I and Q. Just put a fast Analog-to-Digital converter chip at the front end, convert the entire HF spectrum to a digital stream, and send that stream to your computer. Or to another part of your "rig." As in the ubiquitous 7300.
I don't mean to be a Luddite here. That big waterfall is very nice. The receiver sounds great. But I am a homebrewer and I prefer to build my own gear. Ordering this black box on my phone, having it delivered by Bezos to my front step, and then updating the driver, is not what I consider homebrew radio.
A couple of things I spotted: The Si5351 chip in the box -- at least one part was recognizable. And the completely vertical skirts on all the SSB signals -- lots of 7300s out there.
Hey, to each his own, YMMV, whatever floats your boat. Just don't kid yourself into thinking that our beloved DC receivers are still somehow being used in these modern black boxes.
Friday, October 28, 2022
SolderSmoke Podcast #241 Mars, Direct Conversion, PTOs and Glue Sticks, Anniversary of the BITX20, Multus Proficio SDR, Boatanchor Station, MAILBAG
SolderSmoke Podcast #241 is available
Audio (podcast): http://soldersmoke.com/soldersmoke241.mp3
Video (YouTube): (215) SolderSmoke Podcast #241 October 28, 2022 - YouTube
Introduction:
Back on Mars. Opposition
approaching. I have a Mars filter. And (like T.O.M.) a Mars
globe.
N2CQR DXCC done
SolderSmoke in the WayBack
Machine
Sticker news
PARTS CANDY -- Don't Scrimp with a Crimp!
Bill's Bench
School DC RX projects -- in
Hyderabad and Northern Virginia.
Direct Conversion Receivers --
Keeping it Simple, Learning a Lot. A step beyond the Michigan Mighty Mite.
Do we really need 100db? Do we really need to shield VFOs? Farhan's
super-simple and stable Colpitts PTO. Audio amps, 1000-8 transformers and
rolling your own LM386
PTOs and Glue Stick PTOs.
Paul Clark WA1MAC. Brass vs. Steel bolts. #20 thread vs. #28
thread. Backlash Blues. The best Glue Sticks.
2 meters and the VWS.
Bill has a Baofeng.
SHAMELESS COMMERCE:
MOSTLY DIY RF
Pete's Bench
20th Anniversary of the
BITX20 Pete's early BITX rigs.
Computer Woes
The Multus Proficio SDR rig
Simple SSB in China
BA7LNN
Things of beauty: Tempo
One, NCX-3 and a SBE-33
MAILBAG
-- NS7V is listening.
-- Graham G3MFJ
sent SPRAT on a stick.
-- Nick
M0NTV FB Glue Stick and 17 Shelf videos.
-- Dino KL0S
HP8640 Junior
-- Mark AA7TA Read the SolderSmoke Book
-- Steve EI5DD Connaught
(Ireland) Regional News
-- Dave
K8WPE Planting the seeds of ham radio
interest
-- Peter VK3YE
Ruler idea on PTO frequency readout
-- Michael AG5VG Glue
Stick PTO
-- Tobias A polymath with UK and Italy
connections. And cool tattoos.
-- Alain
F4EIT French DC receiver
-- Michael
S. was in USMC, working on PCM/TDM gear
-- Alan Yates
writes up Amazon transformer problem
-- Todd VE7BPO, Dale W4OP, Wes W7ZOI
-- Farhan VU2ESE
sent me an sBITX
-- Todd K7TFC The Revenge of Analog
-- Jim Olds Building QRP HB gear
Saturday, August 27, 2022
SDR on a Breadboard -- But Isn't This an Old-Fashioned Fantasy?
Thursday, July 7, 2022
Would this Really Be Homebrew?
Friday, June 17, 2022
SolderSmoke Podcast #238 -- SolderSmoke Shack South, Cycle 25, Chiquita Banana Radio, RCA, HQ-100, Mate Mighty Midget, Sony SWL RX , Mailbag
SolderSmoke Podcast #238 is available: http://soldersmoke.com/soldersmoke238.mp3
TRAVELOGUE:
Cathartic decluttering: Bill preparing for future winter travel to Dominican Republic. Will build SolderSmoke Shack South. Dividing everything up: Rigs, parts, tools, supplies, antennas, test gear. Everything.
PETE'S BENCH:
Wednesday, June 8, 2022
SolderSmoke FDIM Interview: Jack Purdum W8TEE on the Challenges of Decoding CW by Software
In his interview with SolderSmoke correspondent Bob Crane, Jack Purdum made some very interesting comments about the challenges of decoding CW with software. He notes that W1AW's code practice CW is perfect, but that below 18 wpm, they deliberately insert a "Farnsworth Delay" that increases the spacing between words -- this complicates automatic CW decoding.
Jack also talked about the distinctiveness of different CW operators. Jack noted that W1AW has no real "fist" in this sense: "It has the personality of a stick!"
Jack mentioned that Pete Juliano had been reading book on SDR radios that Jack and Al Peter recently published: https://www.amazon.com/Software-Defined-Radio-Transceiver-Construction/dp/B09WYP1ST8/ref=sr_1_1?crid=2KPYAMPOW5P6J&keywords=DR.+Jack+Purdum&qid=1654598559&sprefix=dr.+jack+purdum%2Caps%2C40&sr=8-1
Here is our correspondent Bob Crane's interview at FDIM 2022 with Jack Purdum: http://soldersmoke.com/2022 W8TEE.mp3
Monday, June 6, 2022
SolderSmoke FDIM Interviews: Hans Summers G0UPL Talks about the QDX and His New Balloon Tracker
Thanks to Bob Crane W8SX for getting us this wonderful interview with Hans G0UPL. Its really amazing to hear Hans talk about how many QDX rigs and Baloon Trackers have been sold by QRP Labs, and how quickly they sell. Really great. Hans's comments on the realities of the parts shortage was also very interesting.
Listen here (about 7 minutes): http://soldersmoke.com/2022 G0UPL.mp3
SolderSmoke FDIM Interview with Farhan VU2ESE -- The sBITX is Coming!
Bob Crane W8SX -- our correspondent in Dayton/Xenia -- once again collected interview with FDIM presenters. Thanks Bob! Here is his talk with our friend Farhan:
http://soldersmoke.com/2022 VU2ESE.mp3
Here is a great post on the sBITX (May 30, 2022) from Farhan's web site:
https://www.vu2ese.com/index.php/category/uncategorized/
Here is Farhan's amazing presentation on the sBITX at the 2021 FDIM:
https://soldersmoke.blogspot.com/2021/11/farhans-amazing-knack-story-from.html
Saturday, May 7, 2022
SolderSmoke Podcast #237 is available: TV Show! No! W9YEI's 1939 TV. 1712 Rig. HQ-100. New SDR Rig and Book. JF3HZB's VFO Digital Dial. FIELD DAY! PSSST. MAILBAG
SolderSmoke podcast #237 is available: http://soldersmoke.com/soldersmoke237.mp3
Travelogue -- New York City! Stickers!
And about that trip to Los Angeles for the SolderSmoke Cable TV show...
Well, it fit in well with SolderSmoke's UNFORGETTABLE appearance on the Oprah book club.
And TechieTatts? Daughter worried about listeners rushing to get tattoos -- A risk we were willing to take.
https://in.pinterest.com/padmakumar10/techie-tatts/
This episode is sponsored by PartsCandy. GREAT test leads: https://www.ebay.com/usr/partscandy
Bill's Bench
Tracking down Johnny Anderson's 1939 or 1940 homebrew TV receiver.
https://soldersmoke.blogspot.com/search?q=Anderson
Working with Joh DL6ID.
Jean Shepherd's January 1973 description.
FlickLives web site and Steve Glazer W2SG have lots of info on Shep and his friends.
Internet allows us to look at TV articles that were being published.
We've concluded: Probably 1939 or 1940, using an RCA 913 1 inch CRT tube.
Lots of ideas from IRE Journal, QST, and Gernsback magazines.
Quite an achievement! Amazing how much pre-war TV progress there was.
17-12 rig
All boxed up and working DX!
Figured out how to display both 17 and 12 on the same LED. https://www.youtube.com/watch?
Drain protector for speaker cover. Copper tape to cover horrible cabinet making.
I think I need a Hex Beam.
Hammarlund HQ-100
Needed some maintenance.
I started to look more closely at it.
Got the Q-Multiplier to work -- it really adds a lot on CW.
Makes me feel guilty about all the QF-1s...
Using the 100kc calibrator with a 455 kc crystal as a BFO,
keeping Q multiplier below oscillation point.
Moved the BFO switch to the front panel. Helps a lot.
Need to fix the S-meter AVC circuitry.
Much more sturdy than the S-38E.
S-38E 1957-61 $54.95 5 tubes. AC/DC.
HQ-100 1956-60 $169 10 or 11 tubes. Power supply, regulator.
You get what you pay for.
Pete's Bench
Jack Purdum and Al Peter's new SDR rig and book (featured on the SS blog Amazon ad).
JF3HZB's beautiful digi VFO.
Backpack antenna for Field Day?
Pipsqueak Disaster -- Too simple?
Peashooter Eye Candy.
Build Something Different.
MAILBAG
James W0JKG CBLA -- Others are building MMM too!
SM4WWG // Jörgen Wonderful message. Joined GQRP. No longer "wrong."
Dennis WC8C Libraries for Max2870 board.
Jack NG2E Progress on the Right to Repair movement.
Jim K9JM Someone cutting into our business with Solder candles!
Chuck WB9KZY Correctly identified the location of the IBEW sticker. As did Dan Random.
Dave Bamford (who lives nearby) suitably impressed.
Farhan wrote to us about a video on Don Lancaster. Homebrew keyboards! Yea!
Dean KK4DAS QRP to the Field. HB2HB 40 SSB QRP I feel virtuous.
Todd K7TFC likes my ingenious use of the drain screen as the speaker protector on the 17-12 rig.
Todd had good thoughts on granular approach to homebrewing as seen in the Don Lancaster video.
Lex PH2LB HORRIFIED by my reverse polarity protection circuit. This is a touchy subject! (as is WD-40!)
Rogier PA1ZZ sending great info on SWL and numbers stations.
Jesse N5JHH -- The guy who made the IBEW stickers -- Liked the NYC stickers.
Steve N8NM has a new antenna article on his blog: https://n8nmsteve.blogspot.
Randy AB9GO Agrees -- Can't GIVE old 'scopes away.
Dino SV1IRG Liked the 17-12 rig videos.
Steve Hartley G0FUW Murphy's Law of Enclosures.
Ralph AB1OP FB on the 17-12 Rig.
Roberto XE1GXG --Our correspondent in Guadalajara. Petulant, irritable people on the computer scene.
Have some gear looking for a good home: Tek 465 'scope from Jim AL7R W8NSA. SBE Transceivers. Windsor Signal Generator. Let me know if you are interested and can either pick up or arrange shipping.
Tuesday, March 1, 2022
Dennis WC8C's FB Homebrew 6 Meter Rig -- Any Ideas or Suggestions?
This is my 6 Meter homebrew transceiver, currently work in
progress. It is a single conversion
super –heterodyne design. I constructed
each stage independently with SMA connectors.
This is so I can re-make sections as needed, and will allow me in the
future to swap sections to experiment with alternate designs. The VFO and BFO are controlled using a SI5351
with an Arduino micro controller. I
currently have separate SI5351 modules for VFO and BFO because I suspected
issues with cross-talk. These issues may
not actually be real, so once I am happy with the performance, I will test
again with just one module to see if it is OK.
The Power Amp is still on the to-do list, so output is well under 0 DBm
The Blue boards were designed by me and ordered
on-line. The other boards I etched
myself. Construction is mostly surface
mount because I find it easier than drilling all the holes. SMD components are mostly 805 and 1206 size.
Transistors are SOT23.
The Band Pass filter is a 5 coil design made with air-core
inductors.
3 bi-directional termination insensitive (TIA) amps are used
(blue boards). Total RX gain is about
44db. Total TX gain is about 16db. Each board has its own independent RX/TX
switching circuitry (mosfet based) and is fed with +12.5, GND, and RX/TX logic
signal from the Arduino (3V logic and up will work)
The Mixer and modulator are both Diode Ring mixers.
The 12 MHz SSB filter is a crystal ladder filter similar to
the one used in the uBitx.
The Mic and audio pre-amp (also a blue board) is made on a
modified TIA amp board. I had 10 of
these boards made, and the needed circuitry was largely the same, so I modified
the board with a rotary tool and jumpers.
The Audio amp is a PAM8403 module and drives a headset. I did make some modifications to the module so
it runs in-spec and to eliminate the power on audio pop.
The challenges I have been having are mostly related to
spurs, splatter, carrier suppression and TX audio quality. I have been gradually tweaking these things
to improve operation before I start on a power amp. My IF is 12 MHZ, and I was using the LSB side
of the crystal filter because it is sharper (VFO 62 – 66 MHz) but have recently
changed over to the USB side of the filter (VFO 38 – 42 MHz). This eliminated the spurs I was seeing near the
pass band. I still need to make some
adjustments to the crystal filter as it is too broad.
I still have some splatter and audio quality seems low, but
I am starting to doubt my test setup. I
see the splatter on the RTL SDR, but I don’t see it on the Tiny SA. The spatter happens at ~160 KHz
intervals. I am hoping to find someone
local with a better spectrum analyzer to help me verify if it is the rig or my
SDR dongle/test setup.
The modules to the side of the picture are my
rejects/experiments. The one covered in
copper shows how I eventually will shield all the modules. I 3D printed a cover for the board, when
wrapped it with copper tape, soldered to the bottom ground plane. The one shown is a diode ring modulator. For some unknown reason the carrier
suppression is rather poor. I had
previously made a junk-box modulator that had much better carrier
suppression. I don’t know why it is
better than the one I more carefully made for the radio, but until I figure it
out, I am using the junk box version.
The junk box modulator uses unmatched schottkey diodes, whereas the
“final” one uses a 4 diode SMD package because I wanted them matched – I
thought this would be better, but maybe not.
Saturday, February 19, 2022
Pete's Eclectic Approach to the Pea Shooter, San Jian counters on Analog VFOs, Non-Restaurant Menus
I liked Pete's comments on the various (analog, digital, mixed) approaches to homebrew:
http://n6qw.blogspot.com/2022/02/2022-return-to-peashooter-build.html
http://n6qw.blogspot.com/2022/02/2022-peashooter-20m-compact-ssb.html
I too have San Jian digital counters watching the stability of analog VFOs (DX-100, HQ-100, Mythbuster).
Variety is the spice of life!
I also liked Pete's comment about the fellow who does on-the-air menu counseling for FTDX-3000 owners. I sometimes run into guys on the air who want to do something similar with my simple homebrew rigs. They start by making comments about my audio -- they will usually say it is "too high" or something like that. Especially when I'm using the separate transmitter and receiver (which have to be "netted" imprecisely by ear), I have to explain that maybe resort to their RIT control would help. If they persist, I sometimes have to tell them that how my rig sounds depends A LOT on the placement of the carrier oscillator relative to the passband of the crystal filter (most recently, the filter from the 1963 Swan 240). Most of them have never had to do that kind of adjustment, so the "technical discussion" usually ends at that point, with my interlocutor saying 73, and presumably moving on to someone whose rig has menus to fiddle with. (Recently heard audio techno term: "massaging the codec.")
To each his own!
Wednesday, January 12, 2022
Looking at the Galaxy's Spiral Arms with a Dongle, a Raspberry Pi,and a Homebrew Antenna
Sunday, December 12, 2021
Hack-a-Day: Has DIY become Click-and-Buy?
https://hackaday.com/2021/12/11/has-diy-become-click-and-buy/
Tuesday, November 2, 2021
Farhan's Amazing Knack Story: From a Boyhood SW Receiver to the Design of the sBITX SDR
-- Farhan talks about his practice of taking the pictures of new rigs with the new rig sitting atop the book that was most important in its design and construction. FB.
-- I was really blown away by Farhan's presentation of how the uBITX advertisement was inspired by and in many ways based on the Heathkit ad for an HW-101. Amazing.
-- I learned a lot from Farhan's discussion of SDR theory. I pledge to spend more time with this. I really like Farhan's hybrid HDR/SDR approach.
-- But I have a question: Farhan seems to say that we'd need a big expensive GOOGL computer to do the direct sampling HF SDR. But doesn't the little RTL-SDR do just that? Without a GOOGL?
-- Great to see Wes's AFTIA being used in the sBITX.
-- Really cool that Farhan has his mind on VHF transverters when designing the sBITX. I liked use of the TCXO module to free up one of the Si5351 clock outputs. FB. And great to include an idea from Hans in this rig.
Thanks very much to Farhan (who stayed up until 3 am to do this!) and to the RSGB for hosting.