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Thursday, September 21, 2017

Herring Aid Error: C14


Yea, take a look at C14 in the AF amp.   At 1000 Hz 10uF is about 16 ohms.  That would put a serious dent in the AF gain.  And indeed, when I went back to my Herring Aid 5 (38 years from start to finish) and pulled C14 out, there was a dramatic increase in AF gain.  

Mistakes happen, but I wonder if anyone else spotted and reported this one.   Could someone with access to the QST archives check to see if an Erratum was ever published?   The project also appears in the 1977 ARRL book "Understanding Amateur Radio" with the problematic C14.  My guess is that it was just an error in the value of the cap.  

Wednesday, September 20, 2017

Can You See an Error in the Herring Aid Five Schematics?



Something caught my eye this morning.  Please take a look at the audio amplifier stages (Q3 and Q4) on the Herring Aid Five.  Can you see an error? Above is the original schematic from the 1976 QST.  Below is a 1998 update by VK1GB and KI6DS.  I see the same problem in both schematics.  Please let me know if you see an error. 






Monday, September 18, 2017

Six Stations Worked on BITX Night


I had a a good session with the BITX gang on 7277 kHz starting at  7pm local last night.  Keith N6ORS was on with his MIN-X rig (picture above).  Michael  KN4EAR's signal is much improved (Michael had worked Barcelona with his BITX40 Module earlier in the day). Randy WB5YYM's rig (featured last week on this blog) was booming in from Arkanas.  

LOG: WI1B Ken on BITX, AA4PG Pat, KN4EAR Mike in Falls Church, N6ORS Keith on MIN-X, W1LY Willy,  WB5YYM Randy in Arkansas

Sunday, September 17, 2017

Hallicrafters and the Romantic Life of Private Hogarth


The world of the SolderSmoke podcast and blog are -- and will remain -- G rated.   But occassionally our discussion of ham radio technology causes us to bump up against some racy topics.  This happens VERY rarely, and that rarity probably says something about ham radio.   We have noted the alleged attractive power of Pete Juliano's French beret.  There was that April 1 story about the new SolderSmoke cologne ("chicks dig it!").  Jean Shepherd was a man of the world -- our discussions of him sometimes bring us a bit closer to the prurient boundary line.  We occassionally mention the lifestyle of the Dos Equis man.  But mostly, we stick to the circuitry.  

This morning I came across a character that I hadn't been aware of: Private (later Corporal) Hogarth.  He was the theme of a series of ads run by the Hallicrafters Company during World War II.  They were trying to sell their EC-1 broadcast receiver (essentially an All American Five).  Their advertising theme was, essentially, "chicks dig it."      



Don't blame me.  I blame Hallicrafters. 

Saturday, September 16, 2017

The Road to QRO Perdition


I want to start out by saying that this is NOT my fault.  I have been TRYING to do QRP things. Remember my recent Tuna Tin 2, Herring Aid 5 rig?    I am aware of the ever-present threat of expulsion from the QRP HoF.   We all remember what happened to poor Pete back on April 1, 2017. 

But sometimes people just deliberately put temptation in your path.   That is what happened this week.  Our old friend Rogier KJ6ETL (formerly known as PA1ZZ) sent me the very LARGE chunk of aluminum that you see in the picture above.  Look at that thing.  It is practically begging to be turned into a very QRO push-pull amplifier.  

At first I told myself that it would be impossible to tap the big heat sinks on the sides.  How would I get the drill in there?  But then I realized that I can just put the threads in from the outside.  I can almost smell the machine oil. And the heat sink compound... 

Thanks lot Rogier. This is all your fault. 



  



Sunday, September 10, 2017

More Stations Worked on Sunday Night with the BITXes

I worked AD0RW, AC9PD,  VE3ZBM and WB5YYM on 7277 kHz around 2345 Z Sunday 10 Sept 2017. BITX ops gather on that frequency on Sunday nights at around 7 pm local time. 

The station above is the impressive all HB 40 meter station of WB5YYM.  That's a 49er on the left, and a BITX40 on the right.  The amp in the middle has 2 IRF510s.   HB mic too.   FB


Wednesday, September 6, 2017

Amazing $49 Rig from QRP Labs

Hans Summers' QRP Labs has an amazing new rig -- The QCX --  that is chock-full of features and FB technology. Hans has long been one of the most innovative guys in ham radio, and this latest rig is one of his most amazing creations.  Like Farhan's BITX40 Module, this new rig is priced in the 50 dollar range. Hams who are paying many thousands of dollars for their "radios" should be asking themselves a question:  Could I be having much more fun for far less money?  This rig is in big demand and there is already a waiting list, so place your order now if you want to work on this during the winter.  Here is the link: 
http://qrp-labs.com/qcx.html

  

QCX Features:

  • Easy to build, single-board design, 10 x 8cm, all controls are board-mounted
  • Professional quality double-sided, through-hole plated, silk-screen printed PCB
  • Choice of single band, 80, 60, 40, 30, 20 or 17m
  • Approximately 3-5W CW output (depending on supply voltage)
  • 7-16V recommended supply voltage
  • Class E power amplifier, transistors run cool… even with no heatsinks
  • 7-element Low Pass Filter ensures regulatory compliance
  • CW envelope shaping to remove key clicks
  • High performance receiver with at least 50dB of unwanted sideband cancellation
  • 200Hz CW filter with no ringing
  • Si5351A Synthesized VFO with rotary encoder tuning
  • 16 x 2 blue backlight LCD screen
  • Iambic keyer or straight key option included in the firmware
  • Simple Digital Signal Processing assisted CW decoder, displayed real-time on-screen
  • On-screen S-meter
  • Full or semi QSK operation using fast solid-state transmit/receive switching
  • Frequency presets, VFO A/B Split operation, RIT, configurable CW Offset
  • Configurable sidetone frequency and volume
  • Connectors: Power, 3.5mm keyer jack, 3.5mm stereo earphone jack, BNC RF output
  • Onboard microswitch can be used as a simple straight Morse key
  • Built-in test signal generator and alignment tools to complete simple set-up adjustments
  • Built-in test equipment: voltmeter, RF power meter, frequency counter, signal generator
  • Beacon mode, supporting automatic CW or WSPR operation
  • GPS interface for reference frequency calibration and time-keeping (for WSPR beacon)

Sunday, September 3, 2017

Nuclear Powered QRPp? Tritium Nuclear Batteries and Plutonium Pacemakers


OK QRPers, it is time to explore another power source.  Enough of the nails in lemons and all that mess.  It is time to go NUCLEAR! Check out the motor in the video above, then look at the video below for more info on how the nuclear battery was made.  Who will be the first to QSO with homebrew nuclear power?  Or has it happened already? 

Mike Rainey -- this seems like the perfect project for you OM.


Oh and by the way, in the course of reading up on this, I learned that we once used PLUTONIUM to power pacemakers.  Check it out:

https://www.mdtmag.com/blog/2016/01/medtech-memoirs-plutonium-powered-pacemaker

And no, today is not April 1. 

Saturday, September 2, 2017

SolderSmoke Podcast 199 Eclipse, Regen, BITX, DC RX, 3D OLEDS, Iphone Boxes, Mailbag


SolderSmoke Podcast #199 is available. 

http://soldersmoke.com/soldersmoke199.mp3

2 September 2017

The Eclipse.  The Floods. 

Sawdust Regen gets John Henry off to a good start. 
Voltage regulators as audio amplifiers

The return of the Simple-ceiver (Direct Conversion)

Ceramic Resonators

3D OLEDS

iPhone Boxes as rig enclosures

Electric Radio on Frank Jones

17 Meter Contacts 

MAILBAG


Thursday, August 31, 2017

VE1LEB's Ergonomic BITX Enclosure (in Juliano Blue)


Wow, Michael's amazingly cool BITX enclosure looks like you could use it to ask Scottie to beam you up. 
Put an end to those freakish contortions -- 3D print yourself an Ergonomic BITX box! Very FB Michael. Thanks. 

Hi Bill and Pete:

I thought you’d be interested to see my ergonomic enclosure for the BITX40. While operating homebrewed regen radios, I noticed that my hands/arms/shoulders were becoming uncomfortable after a while. After thinking about this for a few days, I realized that the dials on the front of these small radios were forcing my hands into freakish contortions—and having both hands on the dials at all times while tuning made matters worster faster! So I did some homework and determined that our arms and hands most naturally hold things toward each other, as though they are holding a small cylinder by the ends. But the conventional “dials-and-speaker-facing-front” radio case forces us to twist our hands up and outwards from our bodies to twist things. See my blog post http://blog.generaleccentric.net/?p=2009 for illustrations of this problem.

My enclosure design for the BITX40 re-orients the volume and tuning knobs toward the sides of the radio, making their operation much more natural—and pleasant. Although it’s not retro, it does have an unconventional appearance and should fit in quite naturally with all the other homebrewed solutions featured on SolderSmoke. 

You can visit my post at http://blog.generaleccentric.net/?p=2082; the box is available for download and printing at Thingiverse: https://www.thingiverse.com/thing:2508147

By the way, I also have a 3D printable mic for the BITX40: https://www.thingiverse.com/thing:2500483

73, Michael VE1LEB

Tuesday, August 29, 2017

Something else "Completely Different": Meteor Pings



Very cool.  I want to try this.  I have the RTL-SDR and the software, so all I need is the antenna.  I may try to resurrect the 5 element 2 Meter Quad from my 90's adventures in the Dominican Republic (I still have the copper tube elements!).  I know the Graves radar is out of range, but there must be a suitable North American signal for this kind of thing.  Any ideas? 

For more info:
http://hackaday.com/2017/08/27/sorry-us-europeans-listen-to-space-with-graves/#more-270298

https://dk8ok.org/2017/08/23/graves-reflections-out-of-the-blue/

Sunday, August 27, 2017

Knack Victim Makes Good! Alan Yates in Seattle



Jean Shepherd used to say that in life, many of us come to a fork in the road:  down one path lies success.  Down the other, ham radio flea markets.  Alan Yates is proving Shep to be WRONG. 

I have fond memories of Billy and I building many versions of Alan's trivial electric motor.   We look forward to his virtual reality.  

Saturday, August 26, 2017

K.P.S. Kang's Speech Processor and Antenna Tuner for the BITX (and other rigs)


Check out the blog of homebrew wizard K.P.S. Kang.   OM has a nice speech processor based on the LM386.   He also has a very simple antenna tuner and SWR bridge.  FB OM.  

http://smallwonderqrp.blogspot.com/2017/08/two-essential-add-ons-for-bitx-and.html

Thursday, August 24, 2017

The Return of Pete's Simple-ceiver Plus (and a possible analog option)


Winter is approaching ladies and gentlemen, and it is time to think about radio projects.   Bob N7SUR suggested a direct conversion receiver project.  I think this is a great idea.   As a kid, I had fallen victim to the idea that building receivers was "too hard" for radio amateurs. Not true!  DC receivers to the rescue!  Carry on with the DC revolution first launched by Wes W7ZOI in 1968.

Pete N6QW is providing guidance and tribal knowledge via his blog.  For those of you who want to join the ranks of those who have defied the conventional wisdom and have broken through the "receivers are too hard" barrier.  I say build yourself a DC receiver.  Build it from scratch.  Many of you already got your feet wet in homebrewing with the Michigan Mighty Mite project.  Now it is time to jump into a DC receiver project.  

You folks already know what kind of VFO Pete will prefer:  It will be an Si5351.  That's fine.   But I will try to keep the banner of discrete component analog ludite-ism flying high.  This morning I ordered a batch of 7.37 MHz ceramic resonators.  I hope to pull them down into a significant portion of the 40 meter phone band.  If this works, I will share the batch with anyone who wants to joining my Analog Army (remember the CBLA?).   Note (above) that Pete has magnanimously left open the possibility of using a non-digital VFO. What a guy!    

Check out Pete's project here: 

http://n6qw.blogspot.com/2017/08/a-new-line-of-transceivers-difx_19.html

Sunday, August 20, 2017

Pre-eclipse Solar Observation


I'm not sure if I'll be able to get a look at the eclipse tomorrow -- I'll be at work,  and in any case Washington DC will be far from the zone of totality.  But all the eclipse talk made me want to get my old 4 inch reflector telescope out today for at least one solar observation.  And yes, I know not to look through the 'scope. I projected the image onto a piece of white paper.   Notice the three large sunspots at the center of the solar disk.  Pretty cool.  

BTW, it is easy to aim the scope at the sun without endangering your eyesight.  Don't ever put your eye to an eyepiece (even on the spotting or aiming 'scope) when ole' sol is in the sky!  Instead, just look at the shadow that the scope tube is casting on the ground.  Make it circular and you will be very close to having the main tube aimed at the sun. See below.   



 I like to have the eyepiece aimed down at the ground or well above horizontal to avoid the danger of someone accidentally walking through  the powerful sunbeam coming out of the eyepiece.  You do have to be careful, especially if there are kids around. 

Saturday, August 19, 2017

Building an Airplane in the Basement with Insulation Foam, Tape, Glue, Poplar...



But this one is not a model RC plane.  This kid intends to pilot this plane while actually sitting in it.  

As a parent, I must say this is really nuts.  Stick to the models Peter!  Or maybe put some goggles on the big dog and let him fly it!  

Nevertheless, this is an inspriational look at what can be built in a basement using stuff from Home Depot or Lowes.    

For more info see:
http://hackaday.com/2017/08/14/building-an-ultralight-out-of-foam-in-a-basement/#more-268614

Here's Peter's earlier Cargo Plane project:



Friday, August 18, 2017

Voltage Regulators as Audio Amplifiers - Who Knew!?

Mike KC7IT pointed out that the AF amplifier chip in my Sawdust regen receiver is actually a TL431 voltage regulator. Mike writes: "It's using the voltage reference input as audio in, and the voltage being regulated as the audio out."  It works great as an audio amplifier, and with just three terminals it is a lot easier to use than our normal LM386 or 741 chips. I'd never seen a regulator used this way.

Here's the data sheet:  http://www.ti.com/lit/gpn/tl431

And here are a couple of sites that discuss this very interesting repurposing:

http://theradioboard.com/rb/viewtopic.php?t=6733

http://techlib.com/electronics/audioamps.html#TL431

Wednesday, August 16, 2017

A Regen that is NOT Evil



Look at that thing.  It is already painted Juliello -- this is a very good sign.  Steve Silverman sent me one of these Sawdust Regen kits a few years ago.  I put it together this week for my nephew John Henry who is very interested in Morse and ham radio.   

This is a regen that even I can love. It is simple, small and stable.  40 meters comes booming in.

Look at the schematic.  Why haven't we used that simple three-terminal AF amp IC before?   



Tuesday, August 15, 2017

International Brotherhood and the BITX Rigs

Bore and Heriberto's uBITX board
Nowhere is the International Brotherhood of Electronic Wizards more evident than in the work on the rigs designed by Farhan.  With the BITXs we see rigs designed in India that are now being built and modified all over the planet. Here are just a few examples of the global collaboration currently underway:

In Italy, Giuseppe is putting a BTX40 on 20 meters and making it a dual bander: 

Hi everyone, I just completed some tests on a Bitx40 running in 20 meters band. I addes the 20 as secondary band activate when needed. I apply some mods to switch to secondary QRPLab BPF filter centered to 20 meters and removed the C91 and C92 caps to work in USB. I done some RX tests in the weekend of iaru hf contest to listen some stations Active.
Here the issues registered:
1) the 20 RX sensitivity was a bit weak compared to 40 meters. I need to increase volume. ( To receive the 20 meters the vfo run to 26 MHZ, mybe some stage suffers of poor performance in this High frequency?)
I also tryed to increase the vfo over maximum allowed by raduino, using external buffer, but no results.
Please read the issues as: work but could work better!
2) the RX was not very clean: voice acceptable, but RX of Digital mode not very stable ( probably the cause could be the vfo shift for poor tuning control. I need to add lock function in firmware ...) Or interferences for free wire of connection.
3) Sometimes when switch on or change vfo to other band or mode, the bf amplifier start a self oscillation ...Resulting in my wife's screaming (the tests were also performed during the night!)
No tests was performed at the moment in TX because i need to install the LPF for the new band.
The firmware to make the test was a modified version of 1.17.1, few temporary mods to preset the vfo b to 14 MHz USB and correct the freq. Display.
These my tests.
Giuseppe Callipo IK8YFW.

Pavel is a young fellow in Cuba who is doing great things with the Raduino software: 

My Photo

Hi to all.
The code was updated, the change log is this:
v1.4Update to catch up with the features added in the Raduino v1.17.1 from Allard's code (CW SPOT and bug fixes)
  • Upgraded the operations instructions
    • More user friendly version with embedded images.
    • Add instructions for the S-meter, AGC and TX-power mods details and tricks.
  • Moved all images to its own folder "images".
As usual tips/bugs/comments/suggestions are welcomed, you can reach the code here: https://github.com/pavelmc/bitx40/
There is a inoffensive bug in the calibrate process, in which the actual calibrate value is not correctly showed in the LCD until you move the pot to adjust it, I'm working on it.
I'm slowly working in this direction now:
  • Bug removal in the calibrate function.
  • Finish the upgrade of the Si5351mcu lib with some improvements.
  • Adding CAT support via ft857d lib (https://github.com/pavelmc/ft857d):
    • Full compliance needs get rid of all the blocking delay() sentences and that need a structural/paradigm code change and a lot of testing (I have Fldigi/MixW/Hamlib to test, I think if that 3 works the rest will do it)
    • Moving to a library (yatuli: https://github.com/pavelmc/yatuli) for the pot usage, that will ease the process of implementing the CAT as almost all delay() calls are related to pot/clicks, so I'm on it.
    • Maybe implement a multiclick lib to optimize the code and make it more easy to understand.
 Any thoughts or whishes related to that?

I plan to make the CAT operation optional via a #define declaration as not all of us will/want-to use that.
73 Pavel CO7WT

Here we see Bore in Montenegro working on a uBITX designed in Cuba by OM Heriberto

Hi Colleagues
Bore Lezaic from Montenegro is working on the uBitx PCB designed by Heriberto -CM2KMK- from Havana, Cuba
Here some pictures he(Bore Lezaic) have posted in my FB wall.
Any question regarding uBitx PCB please send to Heriberto Gonzalez Mendoza at cl2kmk@frcuba.cu (please take care with the email address it is slight different to his actual call sign).
Qrv's
73's Jc

Bore and Heriberto's Board
Hidehiko in Japan was struggling with some LCD noise in his experimental BITX40.  I passed along the active filter circuit that I'd first seen in Roy Lewallen's Optimized QRP rig. 

To
BITX20@groups.io Jul 29 2017 at 4:22 AM I've finished the Bitx40 experimental project today. I added the AF-AGC and LM386 POP limitter with raduino v1.20.1 (Thanks Allard). And I also added the DuinoVOX for Digital Mode operation. It's a great radio but the problem is only the "LCD noise" when increasing the AF volume. hi... Can I reduce this noise? Or I have to use the analog VFO? Any suggestions welcome.
ja9mat Hidehiko

To Hidehiko JA9MAT: 
Very simple.  Just three parts.   NPN transistor (like a 2N3904) and a 47k resistor (collector to base) 100 uF cap (base to ground).   Vcc the collector. Emitter goes to the DC power input of the AF amplifier.  You can see my use of this circuit in the schematic in this blog post:
Look in the lower right, near the LM386 AF amplifier.  Click on the schematic to enlarge.  73  Bill N2CQR 

Thanks Bill,
Well I added "3-parts"(2N3904+47kohm+100uF) between the D18(1N4148) and the junction of R111(100ohm) and R1113(220ohm). The noise has absolutely gone!
ja9mat Hidehiko.
_._,_._,_

Monday, August 14, 2017

ZL2CTM's Homebrew Transceiver Project



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

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

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

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

More of Charlie's work here: 

https://plus.google.com/107506245856154702088

Sunday, August 13, 2017

Audio Clips from N2CQR/HI8 Contacts with MIR Space Station (now in mp3)


Back in 1995 I was in the Dominican Republic.  I used an old 2 meter rig and a homebrew 5 element quad (see below) to talk to U.S. Astronaut Norm Thagard on the MIR space station.  (You may have heard me bragging about this before.) I made a bunch of audio clips from the contacts.  They'd been in the now defunct RealAudio format, but I have been able to convert them to mp3.  You can listen here: 

http://www.gadgeteer.us/CLIPS.HTM




Saturday, August 12, 2017

Real-Time 3D on an OLED Display


Oh man, I thought I was so cool when I got the OLED to display 7215 kHz and other frequencies.  Then I see this.  What next?  Real-time 3D SDR Waterfalls?  On an OLED?  Holograms?  

From: 
http://hackaday.com/2017/08/08/atmega328-3d/#more-267887


Friday, August 11, 2017

Alaskan Road-Kill Microphone


I got a kick out of Paul's message from Alaska -- on my bench I have an almost identical project, including the sink strainer (see below).  And of course the now-iconic SolderSmoke podcast mic is just an electret element inside what used to be an IKEA floor lamp. 

N2CQR Lamp Mic 
Hi Bill and Pete,

I have been following your and Pete’s adventures on Soldersmoke for a while and want to say that each episode always brings some of my past experiences to the surface.  I have been fiddling with radios and electronics for over 60 years, licensed since 1964.
I needed a mic for Bitx40 build and started thinking about this as I was working on other projects. Every day I walk a mile and a half to my mailbox. Wednesday’s and Friday’s happen to be the days of trash pickup and people put the trash bins out next to the road for pickup.  Last week I spotted a little desk lamp sitting on top of one of the trash bins with the cord cutoff so on my return from the mailbox it was still there and it followed me home.  (fig1)
Removing the shade left a flexible vertical support for a mic, (fig 2).
Your recent podcast you mentioned your D-104 microphone, that was my first mic once I had phone privileges back in ’65.  Scrounging through my treasure box I came across a 1 ¼” to 2” PVC pipe coupling that looked just like the basis for a mic. A few hours of mediation and a couple hours at the lathe and mill produced a mic with stand and a PTT switch (fig 3).
Some scrap bin aluminum and a free lamp from the trash and another hour at the lathe, (fig 4 & fig 5). And yes, it has some heft as the base has a large hunk of cast iron in it. Will admit I spent $1.24 for the sink strainer that sacrificed itself to become the grill ala D-104.
The self-satisfaction of building your own gear and accessories is one of the rewards of this hobby, can’t buy that in a store. And repurposing someone’s trash into something useful is a plus.

Keep the soldering iron hot.
73’s
Paul KL7FLR
Wasilla, Alaska
PS JoAnn’s is one of my favorite places for finding useful materials.






Thursday, August 10, 2017

Please Help This Guy


From time to time we use the SolderSmoke blog and podcast to try to help those in need.  We have close ties to the Dominican Republic and often become aware of people who are in real trouble in that country.  Here is case of a man who really needs some assistance.  Please take a look and consider helping him out.
https://www.gofundme.com/ramons-medical-treatment

More on K0EOO's Amazing Homebrew SSB Rig



Hello Bill,

The rig was my own design based on an article by Guy Gillet, ON5FE, published in QST, Jan 1970. (Editor's Note:  ON5FE's article also appears in the 1970 edition of the ARRL's book "Single Sideband for the Radio Amateur.") His article had some features I wanted and became the guts of the transceiver I finally came up with…  The rig took me some 2-4 years to complete mainly because I keep changing circuits and improving performance.  For example, I started with a 4 digit counter using nixie tubes and ended up with 7 digit 7 segment LED counter summing the BFO, VFO and HFO.  I also later added the keyer and CW audio filter and so on…..

Other than the outer cabinet from LMB, I did all the metal work complements of the metal shop at our lab at CDC’s advanced design lab.

Pictures show bottom with RF bottom plate installed and bottom view of RF section with plate removed.  Front panel and picture of top cover open showing the plugin PCB’s.  Cannot see the digital counter display board in any of the pictures.

Here are a couple pictures of the old girl.  I’ve added a description of the rigs features:



Features:
  • Dual conversion, first IF tunable, second IF fixed
  • RF clipping
  • 7 digit readout of exact operating frequency (digital summation of BFO, VFO and HFO)
  • All solid state except for 6146 and 12BY7 driver.
  • RF gain is 0-60dB step attenuator on input
  • Dual VFO’s for separate receive/transmit or transceiver A/B
  • Modes are USB/LSB/CW
  • Auto zeroing S-Meter
  • Built in VOX and PTT
  • Built in CW keyer and sidetone generator
  • Built in CW audio bandwidth filter
  • Built in Tune mode
  • Built in RF Clipping lever control
  • Built in keying to PTT external amplifier
  • Output signals for SB-610 scope receive signal monitoring
  • Output signal for SB-620 Scanalyzer panadapter
  • Diode T/R switching through out the radio, no relays, totally silent TR switching

Well Bill, you opened Pandora’s box when you asked me for more details, hi, hi…  You can almost see the buttons popping off my vest as I reminisced the feature list…

Regards, Dennis, K0EOO



Wednesday, August 9, 2017

K0EOO: Homebrew SSB in 1974

It is not everyday that you get on 40 meters and run into a guy who has actually built a single sideband transceiver.  But that is what happened to me today.   I spoke to Dennis, K0EOO.  He  showed an unusual interest in my BITX DIGI-TIA.  He went on to explain that he had done some homebewing himself.  In the picture (from 1974), right next to his Vibroplex bug we see his homebrew,  80-10 meter,  dual conversion,  solid state (except for the 6146 final) SSB transceiver with digital readout.  Wow.  That's a beautiful rig.  

Off his right shoulder is a homebrew 700 watt amplifier using dual 4CX250s. And behind his left shoulder we see a homebrew tube-type receiver.

Note the look of pride and determination in OM's eyes.  You can just hear him saying it: "Rig here is homebrew."

More pictures of Dennis and his rigs (including some amazing vintage gear)  here:

https://qrz.com/db/K0EOO

http://www.isquare.com/millen/members/k0eoo.htm

http://www.vintagessb.net/k0eoo.htm

Sunday, August 6, 2017

Thermatrons Al Fresco: W4GON's FB HB AM Rig

I was listening to 7290 kHz with my BITX this morning and I heard W4GON say his AM rig is homebrew.  So of course I fired up the DX-100 and the HQ-100 and gave Joel a call.  Conditions were terrible but we had some support from the radio gods.  

From Joel's QRZ.com page: "It uses a pair of 6L6s in Push-Pull Class AB1 high level plate and screen modulating a 6146. I still have a lot of work to do on this rig, like building an enclosure, but it works and I just couldn't help but getting on the air with it!"  


I think it is a thing of beauty. 



Saturday, August 5, 2017

Let's Give Jason NT7S Some Support!


Most of us are using Jason's code and his Arduino Si5351 libraries.   We now have an opportunity to help him continue to come up with the innovations that keep things moving forward on our workbenches.  

Consider becoming a patron.   Learn more here:  

https://www.patreon.com/NT7S

Thanks for all you do Jason!  


"So You Want To Build?" Words of Wisdom from Pete Juliano


Everything on Pete's blog is worth reading, but this article was so good that I could not resist posting a link to it here. 

Tribal knowledge from a leader of the homebrew tribe: 

http://n6qw.blogspot.com/2017/08/a-new-line-of-transceivers-difx.html

Thursday, August 3, 2017

AE7KI (VK2APG), FT8, and WAS on a BITX20

I've had several very nice conversations with Gerry AE7KI (aka VK2APG).  His Australian accent sets him apart from the other Tennessee stations.  Last time we talked Gerry mentioned having competed Worked All States with his BITX20 (below). Very cool.


Gerry also alerted me to a new digital mode created by Joe Taylor.  This one is called FT8.  Gerry is using it to good effect on the 6 meter band. Here is Peter Marks' initial reaction to FT8:


As I type, there are 252 stations monitoring 6 meters for FT8 signals.   You can see a map displaying these stations here: 





Monday, July 31, 2017

Yellow Fever! The Cold War Origins of Juliello


How could you miss them?  That yellow was bright!  Apparently you needed high visibility to cope with the looming danger of nuclear annihilation.  The operator in the ad is obviously calm in the face of Armageddon -- note the cigarette dangling from his lips. In this 1956 Gonset ad we can see the inspiration behind what -- many decades later -- has emerged as the avant-garde ham radio color scheme known as Juliello.  The roots of this aesthetic are clearly not in the psychedelic "Mellow Yellow" hippie era.  No, this color has harder, more flinty origins.

Pete Juliano is not the only one to embrace this look.   Podcast #198 elicited this response from our friend Armand WA1UQO: 

Pete:
Don't let that Meara guy give you a hard time over the yellow Rigs.  The last three of mine have been yellow and I'm happy to see I'm not the only one with good taste.  In the picture they are from top to bottom a 30M One Watter, a 20M One Watter and of course the BITX 40.  The 20M does have a Juliano Blue cover though to give it an extra bit of class!  As always, enjoyed the podcast.
Bill,  see you at Berryville?
73, Armand WA1UQO



Saturday, July 29, 2017

SolderSmoke Podcast #198 - D-104, HW-8, Juliello, DIFX, Dishal, Baofeng, MAILBAG

Bill Breshears WC3K (SK)
SolderSmoke Podcast #198 is available. 


29 July 2017

Sign on a beach store:  SHACK-TACULAR! 

Noticed that EB63 amp was getting hot. Why?  

TT2, Herring Aid5, Farhan's Key:  QRPp and CW!  See?

D-104 lore -- Reading from Bill Breshear's (WC3K) ER article
Astatic  crystal/ceramic element -- disappointingly flimsy
Electret-ing it.  The G-Spot (see picture above)
Walery KB2FIV sent crystal mic element and piezo buzzer (reverse for mic!) FB
HW-8 AF filter Center Frequency Problem.  IT'S TRUE!  Fixed!  Finally. 

Shack re-org at N2CQR
Got Steve Silverman's HP 8640B Sig gen on the bench.  Required reinforcement

Pete's new DIFX
LM373 rigs.  Perhaps with that CA3020 Pete sent me. Chips Ahoy! 
Juliano Yellow? Origins of Blue?  Juliello? Julionyx? 
HB Crystal Filter Capitulation? Don't give up Pete --  just dish the Dishal!
Ceramic VXOs?  K.P.S. Kang
Crystal testers by G7WKE and Dino KL0S.  Impressive. 

Antennas and BITX40 modules.  Antennas are important.

Bill's new Baofeng HT on 440.

Fixing my Sony SW7600GR

MAILBAG
Steve Silverman alerts us to NYC radio row now in the Bronx.
Tony G4WIF on the cover of SPRAT -- Getting the Don Cameron award. FB 
Armand WA1UQO points out that the Berryville hamfest is coming up... 
Thomas KK6AHT F4HDQ writes in. 
On the air with W8NSA

Juliello.  No. 


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