Podcasting since 2005! Listen to Latest SolderSmoke
Thursday, March 16, 2023
A Very Cool Video with NanoVNA, FFT, LC circuits, W2AEW, CuriousMarc, Back-to-Back 1N4148s, and String-Powered Gyroscopes
Thursday, October 6, 2022
Adding a Diode Ring to the Direct Conversion Receiver, And How the Diode Ring Works
Friday, December 3, 2021
Alan Wolke W2AEW: YouTube Silver Play Button Award, and ARRL Hudson Division 2020 Technical Achievement Award
Sunday, November 28, 2021
How To Understand the NE-602 and the Gilbert Cell Mixer
Friday, August 27, 2021
SolderSmoke Podcast #232 -- Mythbuster, Pete's Tube CW Rig, Pete's DC RX and Simple SSB Rig, NanoVNA and TinySA, Very FB Mailbag
Frank Jones and the FMLA -- Possible Victory?
IBEW Stickers: NASA, Johns Hopkins APL....
Cycle 25 Lookin Better Today: SFI 93 SN 47
Toobular! A Tube Transmitter
SR-160
Simple SSB rigs around the world!
KI7NSS's Pacific 40
The Mythbuster and the Struggle Against the Urban Legend
W2EWL's Cheap and Easy SSB
W4IMP's IMP. Articles in ER by Jim Musgrove K5BZH and Jim Hanlon W8KGI
The Spirit of Homebrew SSB. From Electric Radio K5BZH December 1991
Reduced Front End Gain on the DIGITIA
Back on 17! HP3SS sells HBR receiver to Joe Walsh
Maybe another Moxon?
NanoVNA -- Alan W2AEW helped solve mystery of why NanoVNA not providing accurate readout of circuit impedance. Over driving. Need attenuator.
TinySA -- Limited Resolution Bandwidth. But you can listen with it! See video on blog.
-- Google Feedburner to end e-mails from the blog :-(
-- Paul VK3HN -- TIA AGC? Farhan and Paul looking into options
-- Ciprian's Romanian Mighty Mite
-- Dino KL0S SolderSmoke GIF and graphical presentation on sideband inversion
-- Allison KB1GMX helped me on 24 volts to IRF 510 issue.
-- Dave K8WPE Wabi Sabi and Martha Stewart. And thanks for parts! 40673s!
-- Steve N8NM building a 17 meter rig with 22.1184 crystals in a SuperVXO and a 4 MHz filter.
-- Dean KK4DAS restoring an old Zenith. One hand behind your back OM.
-- Pete Eaton debating SSB or DSB for 17. Go DSB Pete!
-- Richard KN7FSZ a FB HBer. Asked about my solid-stating of Galaxy V VFO.
-- Walter KA4KXX on benefits of no-tune BP filters like Farhan's FB.
-- Jack 5B4APL on Time Crystals and Homebrewing in the 4th dimension. FB OM!
-- Moses K8TIY listens to the podcast with his young son Robert. Crank it in Robert!
-- Farhan and the SBitx on Hack-A-Day
-- Also Tom's receiver from junked satellite rig on Hack-A-Day
-- Todd K7TFC sent in beautiful message about the spirit of homebrewing. On the blog.
-- Grayson KJ7UM was on Ham Radio Workbench with George Zaf
-- AAron K5ATG running a uBitx with a homebrew tuner and antenna. Hope I can work him
-- Heard Mike WA3O last night on 40 DIGITIA. Water cooled amplifier
Sunday, July 18, 2021
Alan Wolke W2AEW's Great Video on Using NanoVNA to Measure Amplifier Input Impedance and Gain
Saturday, July 3, 2021
M0NTV's Latest Breadbox Rig -- The Radio Gods Have Spoken (TRGHS)!
Sunday, January 24, 2021
VBE Multiplier Makes KLH Receiver "Cool Running"
Yesterday I turned to the SolderSmoke wizards for advice on how to fix my KLH Model Twenty-one II FM receiver. I had finally gotten the thing working -- it wasn't the speaker, it was the AF amp, probably one of the final transistors was blown. I replaced the finals and the driver. For the finals I used a TIP29C and a TIP30C. For the driver a 2N3906. With this fix the receiver was sounding good, but the heat sink on the AF amplifiers was way too hot.
If you look at the comments in yesterday's post, you will see some great suggestions on how to fix this problem. The comments and Google led me to Alan W2AEW's YouTube channel and his video on a circuit called the VBE multiplier. Voltage Base-Emitter multiplier. I'd never used this circuit before. It allows you to adjust the bias on the bases of the two transistors in a push-pull amplifier.
This morning I built the circuit on a small piece of PC board. There were just two components: a 10k trimmer pot and a 2N3904 transistor.
With the little board installed, I adjusted the pot for a 1.2 volt difference between the bases of Q6 and Q7. I ended up with base voltage values almost identical to those called for in the KLH schematic.
The receiver sounds very nice now, and is no longer on the verge of bursting into flames. I even made up my own version of the pillow that KLH claimed was necessary for proper acoustic suspension.
Sometimes it is nice to be able to listen to something other than the chatter on the ham bands. And it is fun to do so with a receiver that you have worked on.
I even used some Desitin as a substitute for heat sink compound.
Thanks to Rogier for the receiver, to ZL2DEX, K0EET, W2AEW and David McNeill for the good advice. And to Dale K9NN who sent me a box of parts from which emerged the 10k pot I used in this project. Thanks guys. 73
Thursday, December 10, 2020
Pete Juliano's Presentation to the 2020 G-QRP Club Convention -- Building SSB Transceivers
Tuesday, September 8, 2020
Builds Oscilloscope at age 12! Nick has THE KNACK
Thanks to Grayson Evans for sending us this very encouraging video.
It is from Tektronix; I wonder if Alan W2AEW provided some ideas and inspiration?
More stories like this: https://www.tek.com/stories
Sunday, July 26, 2020
Alan Wolke W2AEW on IMD, NanoVNA and more (presentation to UK club)
This video is another reminder of how lucky we are to have Alan Wolke W2AEW as a fellow radio amateur, and as a teacher and mentor.
In this video, Alan is talking to the Denby Dale Amateur Radio Society in Yorkshire, UK.
The first part of his talk is about IMD products, the importance of 3rd order products, and the benefits of attenuation.
The second part of the talk (after a few questions) is a look at the NanoVNA, which Alan cites as the "Toy or Tool of the Year."
I learned a lot from both portions of the presentation. I now find myself wanting an H4 model of the NanoVNA (bigger screen). Or maybe even an F model. Thanks to Alan, I now know what S21 and S11 means.
Thank you Alan, and thanks to the Denby Dale ARS.
73 Bill
Wednesday, June 10, 2020
Alan Wolke W2AEW Explains the Vector Network Analyzer (VNA) (Video)
I told Alan that his video on VNAs was -- for me -- very timely. The video popped up on YouTube on the day than my NanoVNA was being delivered. TRGHS.
Alan does a great job in explaining what the VNA does. Particularly useful for me was his explanation of the VNA's ability to measure phase differences (through the use of directional couplers).
I am having fun with my NanoVNA, happily measuring SWR and the bandpass characteristics of various filters. Mine came with what looks like a guitar pick -- this is used as a stylus to hit the small boxes on the touch-screen. A nice touch...
I wish there was some good software for use with this VNA. Apparently the nice software described by Joe Smith (yesterday's blog post) is quite expensive. Is there a free alternative out there?
Thursday, June 4, 2020
No Main-Tuning Reduction Drives in Stock Drake 2-Bs -- But why no mod articles?
Saturday, February 29, 2020
How to Measure Output Impedance (video)
Thanks to Tony Fishpool G4WIF for alerting us to this very useful video by Alan Wolke W2AEW.
Alan's video channel is a real treasure-trove for homebrewers.
It was very cool to see "AEW" inscribed on the function generator that Alan built 30 years ago.
Be sure to stay to the end of this video for some electronics humor from Alan. (Steve Silverman: Take note -- we might want to add this to the lexicon.)
Now I'm going to search Alan's YouTube channel for a video on how to measure input impedance.
Sunday, May 26, 2019
DIY Waterfall -- A Quick and Easy Panadaptor Using a Sig Gen and O'scope (video)
Anyway, in an effort to counteract all of this waterfall seduction and to show that us analog HDR guys can go panoramic too, I decided to try to create my own panoramic display without resort to SDR.
Of course, this is a very old technique. It was invented in the 1930s by Marcel Wallace, F3HM. He was the inventor of the Panadaptor which was the forerunner of today's waterfall. Panoramic reception was used by the armed forces during WWII. In 1946 Hallicrafters marketed a Panadaptor for its ham radio receivers (see below).
In figuring out how to do this, I thought back to my use of my Feeltech signal generator to scan the response of a crystal filter. The Feeltech has a very handy sweep feature.
In this case I set up the Feeltech to sweep from 4.85 MHz to 4.75 MHz in one second. With the 12 MHz IF of the BITX40 module, this would result in a sweep from 7.150 to 7.250 MHz.
The sweeping Feeltech just replaced the VFO on my BITX. I hooked up the Rigol oscilloscope to the audio output of the BITX. I set the horizontal scan rate at 100 ms per cm. This would have the trace go across the whole screen in 1.2 seconds.
After a bit of fiddling, I could see signals on the 40 meter phone band. But my display would kind of drift along the screen making it hard to know the frequency of the signals I was seeing.
Alan Wolke W2AEW provided the solution. He advised me to put a big stable signal at 7.150 MHz near the input of the BITX, then use this strong signal to trigger the 'scope scan. The HP8640B signal generator that Steve Silverman gave me (and that Dave W2DAB picked up for me in NYC) provided the triggering signal.
I put a piece of tape across the bottom of the scope display to calibrate the display. See video above.
It works! It is not as cool as the SDR waterfalls, and it does not convey nearly as much information, but it was a fun project.
Tuesday, January 8, 2019
Old Station On-The-Air -- A Transmitter Half as Old as Radio Itself
The Drake 2B's 50 kc and 405 kc oscillators were right were they were supposed to be -- no adjustment required. And I don't think they have been peaked since 1973. The 455 kc IF can was also very close to perfectly tuned.
Since most stations from the mid-1960s had some QSL cards on the wall behind the rig, I pulled out some old ones and put them up. Many of these contacts were made by the rigs in the picture.
If we say that 1897 marked the first use of radio, and if we assume that this HT-37 was manufactured in 1959, that means that my old transmitter has been in operation for almost HALF of the history of radio.
Tuesday, May 30, 2017
Farhan gives me a Spectrum Analyzer and W2AEW Provides the Tutorial (Video)
At Dayton, Farhan very kindly bought me a Tektronix Spectrum Analyzer. (I joked during his visit that this device might help me stay in the good graces of the FCC.) This morning I decided to learn more about this device. I Googled "Tek 1401A" and was immediately directed to a YouTube tutorial. I was pleased to see that it was from our old friend Alan Wolke W2AEW. I knew that the Tek analyzer and I were in good hands. TRGHS. Alan expertly laid out the functions of the device. I am confident that I will soon be analyzing the spectrum of my homebrew rigs, and that they will all be found COMPLETELY FREE of spurious emissions.
Alan's tutorial is instructive for all those getting started with spectrum analyzers.
I need to find a manual and schematic for the 1410A.
Thanks Farhan. Thanks Alan. And three cheers for Beaverton, Oregon!
Saturday, September 10, 2016
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/
Sunday, March 6, 2016
"My Favorite Programming Language is Solder" -- Boldport Kits
Here is their main site: http://www.boldport.com/blog/2016/2/21/boldport-club-project-1
Here is where you can subscribe to receive a monthly project (with parts!) from them:
https://boldport.cratejoy.com/
As for the solder quote from Bob Pease, this was discussed before on this blog, back in 2011. We were talking about an intereview that had been done with Alan Wolke W2AEW:
I also liked Alan's response to the question about his favorite software tool: "Gee, solder is soft, can we consider that software? I use a lot of that!" This is very reminiscent of a quote from the legendary Bob Pease (colleague of Jim Williams): "My favorite programming language is solder." (That quote was sent to me by Steve WA0PWK. Thanks Steve.)
Thursday, January 28, 2016
Alan Wolke W2AEW Builds a Michigan Mighty Mite (Video)
We are honored to induct Alan Wolke W2AEW into the Colorburst Liberation Army. And for his valiant effort to build and explain a MMM Low-Pass filter, he is immediately promoted to the rank of CBLA Two Star General. Congratulations General Wolke.
As is the case with all of his videos, this one has already had an impact far and wide. Ian writes from far-off Western Australia:
73,Ian VK6MIB
Seriously, there is a lot to be learned from the lowly Mighty Mite especially regarding impedance matching; not to mention LC circuits, link coupling, amplifiers, oscillators, etc. . What fun!
73.......SR