Blizzard Prep Priorities: Protecting the 160 meter L network!

I'd been meaning to build a proper cover for my improvised 160 meter L network. The approach of Winter Storm Jonas pushed me into action yesterday afternoon. 

First I mounted the variable cap (from an old Johnson rig) and the roller inductor on a suitably sized piece of wood:

Then I put the tuner inside an old cooler.  I drilled holes in the bottom for the coax and the antenna wire and the ground.

Here it is at the feed point.  Pretty cool, don't you think?

And here it is 24 hours later:

The blizzard has been quite impressive.  Early this morning it featured lightning and thunder!

Some Inspiring Phasing Philosophy from KK7B

KK7B holding his original Mini-R2

Rick Campbell KK7B concludes Chapter 9 of "Experimental Methods in RF Design" with these inspiring words:

"An amateur who has built up a phasing receiver, looked at the I and Q channels on a dual trace oscilloscope, and tweaked the phase and amplitude adjustments while listening to an opposite sideband signal drop into the noise acquires a depth of understanding far beyond that of most wireless graduate students and many of their professors. The best part is that understanding of phasing systems comes from experimenting with simple circuits and thinking -- the tinkering comes first -- then the understanding. In this area the amateur with his simple workbench; primitive test equipment; and time to contemplate, has a profound advantage over the engineering student with a computerized bench and exam next week, and the professional engineer with a million-dollar lab and a technician to run it."

N2CQR Frankenstein R2 showing I and Q audio outputs

(No exam next week for me!)

Lee Snook W1DN's Amazing New Rig

Wow, I feel myself being pulled into the digital vortex.  What a cool combination of digital and analog construction!   I love that small spectrum 'scope.

Lee's rigs and his workshop have been discussed on this blog before:

http://soldersmoke.blogspot.com/2014/11/the-amazing-rigs-of-lee-snook-w1dn.html
http://soldersmoke.blogspot.com/2014/11/the-amazing-rigs-of-lee-snook-w1dn.html

High-Pass Filter Knocks Down AM Broadcast Interference

WFAX 1220 AM was starting to bother me.  Each morning, I'd be drinking my coffee, listening to nice roundtables on 160 meters, when, right at 6 AM, WFAX would fire up its 5 kW AM transmitter, 1.5 miles from my location.  And they would crush the "front end" of my R2 phasing receiver.  It doesn't take much to do that, since the only thing between the SBL-1 mixers in the R2 and the antenna is a signal splitter.  Obviously I needed some filtering. 

I turned to the free program called Elsie (L-C, get it?) and quickly whipped up a design for a seven element, capacitive input high-pass filter that promised to take about 45 db out of WFAX's sails, without attenuating even the lowest end of Top Band. 

Last night I scrounged through the junk boxes and found suitable capacitors.  A visit to an on-line toroid calculator showed that around 35 turns on a T-50-2 (red) iron powder core would yield the needed 6 uH coils.   I built the filter  this morning -- picture below. 

It works very well.  You can see the results in the picture above.  The yellow trace on the 'scope shows the signal at the antenna terminal.  Yikes, it shows around 4 volts rms at 1.220 MHz (the scale is 5 volts/div).  The blue trace below is on the same scale -- this is the signal coming out of the filter.  Not enough to really measure on the 5 volts/division scale.  

This was a very satisfying "quick and easy" build.   I really like the sound of the R2, so much so that I'm not firing up the DX-100 as much as I had been.  Instead I find myself just listening to the R2.

Another AM Broadcast Interference Story

Bill,Pete

Another great solder smoke podcast today.  I especially liked the detail
of you using the S-meter to check on the local broadcast station, and
the better reception you had on 160 with a resonant antenna.  Before I
retired I had spent over 25 years as a field service tech working on
neurological instrumentation.  One of the test our instruments performed
was called an Electro-Myography. Part of this test involved a needle
electrode being inserted into a muscle.  This was fed to an
instrumentation amplifier connected to a computer that processed the
output of the amplifier.  The signal from the amplifier was also fed to
a speaker so you could also hear the response of the muscle fibers
activating as you flexed the muscle.  One of my customers called and
said that quite often when he inserted the needle electrode, he heard
music  instead.
I made a trip to his office and  using a field strength meter, I could
see the modulation peaks on the FSM.  But only in one location against
the wall in the exam room.  I at first thought it might be from a
speaker cable for their intercom / background music system in the wall. 
But there was no wires near that location , and it was an outside
wall.  I went outside with the FSM and found that the signal was coming
from the down-spout for the rain gutter. Apparently the gutter was
resonant at the frequency of the local AM station and the received
signal was being radiated through the wall and picked up by the amplifier.
I quickly got the set of jumper cables out of my van and connected the
down-spout to a near by water faucet, the signal went away. After a
quick trip to the local Home-Despot and picking up some heavy copper
wire and a ground clamp for the water pipe I was able to fix this
problem.  It is amazing how broadcast interference can show up in so
many places.

DuWayne

Arduino Problems -- Back from the Ledge

As I was struggling through this, someone -- who will remain nameless -- told me that because of all the technical problems resulting from the many Arduino IDE "upgrades," suicide prevention hotlines now answer all calls with an automated question:  "If you are calling about an Arduino problem, press 1 for assistance."

It got pretty ugly but with the help of Tom up in NYC I managed to get through it. First he convinced me that it is indeed POSSIBLE to upload the latest version of the IDE -- the dreaded 1.6.7.   I just had to REALLY get rid of earlier versions.  This got me past the horrible Bundled Java Runtime Environment problem (who thinks up these names?).

We then worked with the libraries needed to upload the AD9850 code of Richard AD7C.  You see, I work on Arduino stuff.   Then I stop.  18 months pass.  I forget all I learned.  Then I start over.  The pain begins again.  In an effort to break this cycle, I am now taking notes (in the inside cover of Mario Banzi's book).

I am using the AD9850 with a Kanga Arduino shield designed by Paul M0XPD.   It takes the AD9850 output, divides by 4 and puts it out as 2 square waves in quadrature.  I use this with my R2 phasing receiver.   The problem was that the display on the Arduino showed a freq 4 times the actual tuning freq.  Believe me, this gets old fast.  I considered just getting a San Jian freq counter and supergluing it on the top of the DDS box.  I was going to connect this to the square wave output.  That would have given me one readout with the actual receive freq, and another (on the Arduino) showing the (4X) freq coming out of the AD9850.  But that would have been too much of a Kludge. Tom talked me out of it and modified the code so that the Arduino display shows the actual receive freq.   Thanks Tom.  

Armed with the new IDE and with my knowledge of Arduino basics refreshed, I was able to reload the LA3PNA Si5351 code into my 40 meter DIGI-TIA.  But not before having to swap out the Arduino that drives the Si5351.   One Arduino happily accepted the code, another did not.  Why?  Who knows?  It is a digital mystery.  Those little 1s and 0s are fickle you know.

The Radio Gods rewarded me for all this.  At about 5:45 AM today I was listening to a very friendly SSB roundtable on 160.  The guys were getting ready to sign off.  The last one ended the conversation by asking the others to "Be kind.  Smile at your neighbors."  Nice.
Then WFAX AM started the broadcast day at 6 am, wiping out my 160 meter reception.  Next project:  High-Pass filter at 1.7 MHz.

ArduinWoes

Sometimes I really hate those little boards.  Well, not so  much the board as the IDE.  But now that I've built at least two rigs with the little beasts in them (Of course, I blame Pete), I have the need to occasionally update or re-load software. 

I tried to do just that today.  Downloaded the 1.6.7 version of the IDE.  All kinds of weird difficulties.  The real show stopper is a message that pops up an announced that the IDE comes bundled with Java Runtime, but the bundle is missing or corrupted.  No suggestion re what to do...

A visit to the Arduino blog brings no relief.   There ARE lots of messages from others suffering from this problem.  And acknowledgements from Arduino people that the problem exists.  But no solutions.  Any suggestions?    Or should I just retro-fit LC VFOs or VXOs? 

I seem to go through some version of this every time I try to use an Arduino.

73  Bill  

SolderSmoke Podcast #184 160 AM and CW, R2 Phasing Receiver, Mailbag

SolderSmoke Podcast #184 is available

http://soldersmoke.com/soldersmoke184.mp3

16 January 2016
-- The Radio Amateur is BALANCED
-- Pete exhibits CLEAR symptoms of Dilbert's disease!
-- Santa brought me a 160 meter antenna
-- Ground Radial systems large and small
-- Clip lead L network
-- ON THE AIR ON 160!
-- AM contacts
-- SKN 160 CW with sidetone from the DX-100 transformer
-- Stations with character and personality on 160 AM
-- Pending projects for the AM station
-- R2 phasing receiver Trials and Tribulations 
-- Bill's Astatic D-104 goes into rebellion
-- Ramsey Kits closing down
-- SPRAT 165,  Sidetone,   M0XPD's VXO
-- "The Martian"  movie 
-- Little Gustavo is doing well.  Thanks to all.
-- MAILBAG (an especially good one)

Alan Wolke W2AEW Moonbounce with Project Diana

Alan mentioned this in his interview with Eric on the QSO Today podcast.  I really liked Alan's video of the Project Diana moonbounce commemoration.  That HUGE display showing outgoing signals and then the echoes off the moon was really cool.  EME is on my to-do (someday) list. 

N7SUR's Phasing Receiver on an Oregon Pine Board

And here I thought I was the only one.  Apparently not.  Bob LeDoux has also built a phasing receiver using a piece of wood as a base. I note also that phasing guru Rick Campbell KK7B built his Classic 40 DC receiver  into a solid oak wrap-around case.  Bob's receiver is very interesting. That Tayloe Detector is very nice.  Phasing is fun!  As I type I am listening to Lou, EA3JE on 40 SSB with my phasing receiver. 

Bill,

I thought I'd share my breadboard system for receiver experiments.  In this example I have a phasing, single sideband Tayloe receiver. The entire receiver, less VFO, pulls 54 milliamps at 5 volts.

The chassis is a prime piece of Oregon pine.  Be forwarned; my Tayloe receiver doesn't employ a single discrete transistor.

The DDS VFO at the top is the K5BCQ Si570 based RF generator kit.  It reads 56.231 Mhz because the VFO operates at four times the receive frequency on a Tayloe detector.

The receiver consists of five boards. From left to right they are, RF front end filter; Tayloe detector and post detector amps; sideband eliminating phasing filter; eight pole low pass filter; high pass filter and audio amps.

Flexibility is key.  Each stage, or set of stages is laid out on one circuit board which is tacked to the breadboard. Controls and jacks are mounted in scrap circuit board and screwed to the side of the breadboard.

Two parallel lengths of thin circuit board are used for the power and ground strips.  Electrolytic caps are placed at each board power point.  A bit of copper desoldering braid makes the connection between board ground plane and ground strip.

The circuit board is often double sided with the back side used as a ground plane. Holes are only drilled when a ground connection is needed.

Connections between boards are made using .025 diameter header pins soldered to pads.  Wire wrap wire is used for connections between the header pins.  These pins also make good test points.  With SMT construction my intra-board signal lines rarely exceed half an inch.  This eliminates coax cable for many connections.

I like to use eight pin op amps for my designs.  These provide two stages and four poles in each package.  I have a standard board layout.  Using this single board, component selection allows low pass, high pass, band pass, gain, or no gain configurations. Multiple linked boards can be etched at one time and cut apart to meet individual circuit requirements.

Let me give credit to Dan Tayloe who developed the original receiver design in the NORCAL NC2030 CW transceiver.  I also thank Pete Juliano, N6QW and Nick Kennedy, WA5BDU, for help with current design issues.


Bob--N7SUR--

A Good Radio Morning at N2CQR

The Radio Gods were smiling upon me this morning.  I started out on 17 meters and had three nice contacts with European stations:  OH5CZ, a young fellow near Helsinki;  HB8DQL; then RM2D in Moscow. FB.

Then Pete showed up on the Skype. As he has said on his blog, he is still struggling with a family medical emergency, but I am happy to report that he is coping well, making good use of his can-do project manager background and his good sense of humor.  It was great to see him.

Inspired by my talk with Pete, with 40 meter AM playing in the background, I turned to my R2 FRANKENSTEIN phasing receiver.  Last night I completed the 90 degree phase shift network.  This is built around two quad op-amp chips and is designed to take the audio output from the two DC receivers and create a 90 degree phase difference between them.  I tested this stage by sending the same audio into each set of op amps.  I then put one scope probe in the output of one chain of op amps, and the other probe on the output on the other chain.  Wow.  Bingo.  90 degrees of phase shift across the 300 -- 3000 Hz audio spectrum. 

Emboldened by this positive result, I put the completed stages together this morning.  They passed the smoke test.  Then I tuned to 40 meters.   Wow again!  As promised, opposite sideband rejection without resort to crystal filters.  But as luck would have it, I ended up with a configuration that suppressed the Lower Sideband.  For 40 meters, obviously I needed to suppress the other side of zero beat.  But all I had to do to remedy this was to reach into the DDS box and switch the I and Q jumpers on the M0XPD/Kanga UK Arduino AD9850 shield.  This switch put me on LSB.  Very cool.

Here is a view from above:

The AD9850/Arduino DDS box is in the bottom center.  Above that, near the center of the picture,  is the board (from N6QW) with the two SBL-1 mixers and the initial AF amp stages.  The small green board above that is the IC phase shift network.  At the top of the picture you see the 3000 Hz low pass filter. Below that, the board with the little blue pot has an IC AF amplifier and a 300 HZ high pass filter.


I still have to build the audio amplifiers prescribed by the designer, Rick Campbell KK7B.   But obviously I am already having a lot of fun with phasing.  Here is the QST article on Rick Campbell's R2 receiver:
https://www.arrl.org/files/file/Technology/tis/info/pdf/9301032.pdf

N8NM: Thermatron Meets Silicon (Part II or III)

Steve N8NM has been pushing the limits of radio hybridization.  In this receiver he has 12AX7 thermatrons running alongside an Arduino and a Si5351.  Somehow I find this both very appealing and deeply disturbing.  Many of you will know what I mean. But FB Steve -- keep them coming.  Put these unique rigs on the air and strike a blow against the Yaesu-Icom-Kenwood monotony!   

Bill:

Here's a pic of a Thermatron-Meets-Silicon receiver that I've been working on.  Tubes are 12AT7 mixer, 2x6BA6 IF amps, 2x12AX7 (product detector, AGC amp and 1st AF) and 6AQ5 audio out.  An Arduino controlled Si5351 provides the LO and BFO as well as handling all of the switching, and the mixer and product detector use variations on Dr. Pullen's dual-triode circuit.  I've had this one on the air, but the hardware and software still need some, um, refinement.  And painting the panel has to wait until spring as my XYL doesn't share my affinity for paint fumes.

73 - Steve

N6ORS's Min-X Crosses the Pond on First Contact

Very cool!  Reports on new phone rigs keep coming in.  It is great to see them in their "still out on the bench" condition.  And reports of the first contacts are always exciting.  I like the MIN-X name.  This is indeed another testament to the contributions made to the radio art by our friend Farhan.   

Hello Bill,

Well I  just finished tweaking my new rig, I named it Min-X because I outright stole bits and piecesof the BITX and the Minima, thanks Ashhar. I made my first contact today and what a contact!

The contact was made with the rig as shown. The amp is a home brew FET push-pull.

I had a chat with Beth MW0VOW in South Wales! From Wisconsin to Wales on 15w PEP.
Oh, most of the rig was 'noodled' and constructed while enjoying you and Pete on the

SolderSmoke podcast.

Best 73,
Keith N6ORS

ZL2CTM's New Zealand Double Sideband Success

New Zealand and Australia seem to produce an amazingly high percentage of the world's double sideband transceivers.  Charlie ZL2CTM adds to the count.  He took inspiration and circuitry from DSB  hams in both countries and produced this beautiful DSB transceiver.  It is obviously -- as Charlie notes -- chock full of soul.  I definitely identify with his comment about "taming some kind of  electro-mechanical machine" and also, of course, with his remark about the feelings that come with putting a homebrew rig on the air.  So follow the advice of Charlie!  Build a DSB rig and put it on the air!  Make this your ham radio resolution for 2016!  Give it a go!    

Hi Bill:

I have been following you and Pete Juliano for many years now, and thought I would send you a photo of my 40m homebrew rig that I finished yesterday. Hopefully, it will help encourage others to melt some solder and make their own rigs. The rig is based on ideas and designs from Eric Sears ZL2BMI, Peter Parker Vk3YE and of course Pete N6QW. The aim is to make the final version relatively compact so I can take it tramping/hiking here in New Zealand.

The VFO is an AD9850 being controlled by an Arduino Pro Mini. The output is amplified to provide sufficient drive for the balanced modulator. I was using a nice 1” OLED screen to show the frequency, but that generated a huge amount of noise, so I changed to a LCD. Changing frequency is simply a matter of moving the curser left and right then using the up and down buttons to change the number. Very quick and easy. I was contemplating a rotary encoder, but I find those always seem to skip and jump every now and then. Must be the way I use them...   

The balanced modulator is a 4148 diode ring. I do have some SBL-1s lying around, but I thought I’d go with the discrete diode ring for something different. I’m using a standard electret mic and a simple single stage amp. The switch above that switches between phone and CW.

The PA is two stages; the first a 2N3053 and the second a BD139. At this stage it puts out just over 1W into a 50ohm load. I might look to add another stage and get that up to 3-5W.

The audio amp is a simple LM386. I am not running it hard out as per the datasheet as it generates quite a bit of high frequency hiss in that configuration.

Unlike Pete, I don’t have access to a milling machine to make squares to mount the components on. Instead, I use vero/strip board upside down and solder directly to the strips. This works really well for me on HF. I cut tracks with the twist of a small drill bit.

Last night I made two contacts with the rig. The farthest was 527km according to some well known mapping software. Both reports said the audio was ‘very nice’, which was great to hear. The receiver worked surprisingly well too, and I managed to hear stations in Europe.

As for user controls, you will notice that the pots, switches and plugs are all over the place. I did that to keep leads short. I like it as i feel like I am taming some kind of electro-mechanical machine to generate and receive RF.

Anyway, this little rig has a ton of soul in it and is really fun to use. There is something different about making a contact with a rig you built. I really encourage everyone to give it a go!

The next iteration will be a SDR using a Teensy. Rheslip over at Open Emitter has done some great work with that.

73s

 Charlie

ZL2CTM  

TIA-Tube Hybrids from Steve N8NM (Part 1)

Last week Steve sent us a picture of his Straight Key Night rig which consisted of a homebrew thermatron transmitter and a TIA BITX as the receiver.  I asked Steve for more info on the TIA BITX. 

Bill:

Shot these right after making the first QSO using the TIA rig as the receiver.  The Arduino and '5351 are still on a breadboard, otherwise, all of the PCB modules except the filters and PA are installed on the chassis. 

The QSO was uneventful, which is a good thing!
73!
Steve

A SolderSmoke Holiday Charity Appeal -- Help Elisa help little Gonzalo!

We are going "off topic" for a moment, for a good cause.  Listeners to the podcast will have heard about my wife Elisa's strong connections to her home country, the Dominican Republic.  The new year finds Elisa trying to help a Dominican cousin who has a very sick little boy.  Details below.  All contributions large or small from the SolderSmoke community would be gratefully received.  Just click on the link to make a contribution.  And please consider forwarding this appeal to friends or relatives who might also be willing to help.

https://www.gofundme.com/porgonzalo

My name is Elisa Meara, and I am raising money for my dear cousin Eliana and  her 18 month old baby boy Gonzalo.

The week before Christmas Eliana and her husband Pedro were happily preparing to celebrate the festivities with their only child Gonzalo. This was Gonzalo's second Christmas and the first one he would be aware of.   Gonzalo wasn't feeling well and his pediatrician recommended that he be admitted to the hospital for a few days.  "Just another childhood virus" I am sure Eliana and Pedro thought.

But the morning of the day before Christmas they learned Gonzalo was very ill.  The diagnosis was leukemia.   While the world around them celebrated, they were living every parent's worst nightmare.  Baby Gonzalo needed emergency medical attention to save his life.

On Christmas Eve, trying to give their son the best chance possible, they left their home and families behind in The Dominican Republic to take him to Jackson Memorial Hospital in Miami for treatment. The morning of Christmas Day he received his first round of chemotherapy. The treatments will continue for the next six to eight months.

Needless to say,  this young and hard-working couple is devastated.  They are trying to do everything they can to help their baby boy.

While they have health insurance, the costs and expenses -especially those associated with living in a foreign city- are growing very quickly. We are hoping to help ease this tremendous heart-ache and suffering with prayers and financial support.

No contribution is too small and every little bit will help.  You can contribute here:

https://www.gofundme.com/porgonzalo

 And please consider forwarding this appeal to friends or relatives who might also be willing to help.

Happy New Year! Straight Key Night on 160 Meters

A while back, when I first mentioned getting on 160 meters by year's end, Pete suggested I shoot for Straight Key Night.  As many of you know, suggestions from Pete somehow seem to have a way of becoming ham radio MORAL IMPERATIVES.  He seems to be a prophet of sorts, a prophet of THE RADIO GODS.  So following the guidance of the oracle of Newbury Park, I found myself in front of my DX-100/HQ-100 on New Year's Eve, on 160 meter CW for the first time in my 42 years as a radio amateur.

It was great.  A couple hours prior to the official 0000Z start of Straight Key Night I had my first 160CW QSO.   It was with John WA2MUA up in Summit, NY.  John's QRZ page includes this: “Years ago--as a teenager-- in an attempt to get enough wire for 160 I wrapped a quarter wave of wire around a pvc pipe, strapped it to a wooden gutter----burned a large notch in the gutter and could have burned my parents' house down!”   That, my friends, is 160 meter KNACK!  

Then, just minutes after SKN kick-off, I worked John W3LR in Eastern Pennsylvania.  It was also John's first SKN contact.

Next up was Eric NO3M.  Wow, this one was amazing.  Eric was running the homebrew rig pictured above.  On his blog Eric describes the rig:   "The transmitter is running a 89 Clapp oscillator, 802 buffer, 811 final...  Output power is approximately 75W. "

Eric's antenna is even more amazing:  it is a 160 meter four square featuring FOUR aluminum tubing vertical elements with capacity hats and --GET THIS -- a radial field consisting of 22,000 feet of bare copper wire. TWENTY TWO THOUSAND FEET OF BARE COPPER WIRE.  Wow, you just don't run into stations like that on 20 meter sideband.   Eric's blog: http://no3m.net/  But Eric -- a Vibroplex Champion?  On SKN? 

I then worked KC2LSD and K1EEE.  FB!

My last contact of the evening (and the year) was K1WHS, Dave in Maine.  On his QRZ.com page, Dave reports:

“On 160 meters, I have a small setup right at my house. I use a K3 with a homebrew 3-1000 amplifier that runs at 1300 watts. The antenna is an 80 ft Rohn 25 in my backyard with some top loading and shunt feeding.  I laid out a bunch of radials in an effort to get the efficiency up. At last count I had about 107 1/4 wave radials strung out. 160 is the only band where my feedline is not big fat hardline. I use a run of RG-213.  For receive, I have several beverages running in the woods. I use this setup often in the winter as many times, the hilltop shack is not accessible due to heavy snow.   I have nothing up for any of the bands between 160 and 10 meters”.

 Thanks to all of my SKN contacts!  And Happy New Year to all  SolderSmoke readers and listeners! 

N8NM's Straight Key Night Rig

Hi Bill,

 

Just wanted to drop you a line to let you know that I’ve recently discovered your SolderSmoke podcasts and am enjoying the heck out of them!  In fact, you and Pete have inspired me to break away from the thermatrons and delve into the wonderful world of the TIA transceiver, and after several weeks of sniffing rosin, my new rig is now receiving signals without the aid of any external life support!  It’s still a bit haywired, but I’m looking forward to pairing it with my little 6AG76L6 transmitter for a few SKN QSOs tomorrow.

 

I haven’t taken any pics of the new rig yet, mainly because, at this point, there’s not much to see, but here’s it’s little octal-based friend with its AD9850/6AG7 hybrid VFO (works a bit better than the VF-1 that it replaced J):

  

Anyway, thanks for putting forth the time and effort to do the podcast!  All the best to you, Pete and your families in the new year.

 

73,

 

Steve Murphy, N8NM

The K7DYY Solid State Class D Legal Limit AM Transmitter

I was on 160 Meter AM this morning, talking to Chet WB2AHK in New York City.  Chet had a very strong signal here.  He was running a rig that I hadn't heard about before, a K7DYY transmitter.   See above. Very interesting.   Here are the details:

http://k7dyy.com/index.html

Chet's receiver was at the opposite end of the technology spectrum -- like me he was listening on a Hammarlund HQ-100.  He told me that he had replaced the old mechanical clock with a digital "glowing numerals" device.  This got me thinking that that space on the front panel might be suitable for a small frequency counter...

Alan Wolke W2AEW Interviewed on QSO Today! And it is GREAT!

A very cool interview indeed.  But how could it be otherwise?  With Eric on one end of the Skype connection and Alan on the other, coolness was inevitable.

In this interview we are reminded of the FACT that Alan has a major case of THE KNACK.  Proof is found in the way he obtained the wire for his first SW antenna:  he unwound the magnet wire in the yoke transformer of a discarded TV set.  THAT, my friends,  is the stuff that KNACK is made of!  

Check it out:

http://www.qsotoday.com/podcasts/w2aew

I share Alan's affection for the TEC 465 'scope, but I twitched a bit when he said it is "easy to work on."  It scared the hell out of me!  It features both plug-in transistors and lethally high voltage -- so high that Alan had to lend me a special high voltage probe just to do the measurements.   

Alan's mention of Project Diana and the history of moonbounce reminded me of Ross Bateman, W4AO, the wizard who, in 1952 bounced the first amateur radio signals off the moon.  He did it from the town I live in now, Falls Church, Virginia. Alan provided me with the address from which the signals were launched. 

Thanks Alan! Thanks Eric!  

First Contact on 160 Meters

Hooray!  After 42 years on the ham bands I have finally made a contact on 160 meters.  And it was on AM, using John Zaruba's DX-100.  My antenna is the 185 foot wire that I mentioned in yesterday's post.  I built an L network using a roller inductor and a bread-slicer cap -- the network is at the base of the antenna.  Before dawn this morning I threw my call into a round-table on 1885 kc.  Pete WA1SOV up in Connecticut heard me and we had a short contact. Hooray! 

I hope this puts some pressure on Steve Silverman and Pete Juliano -- they have sworn A SOLEMN OATH to get on top band.  I'm especially worried about Pete's adherence to this pledge -- he seems to be going a bit wobbly on us, playing with Raspberry Pi's and things like that.  C'mon guys!  Top Band awaits!

My antenna needs improvement.  More radials might help. 

"Receiver Here is My SWR meter OM..."

Santa managed to include in his delivery some of the materials that I needed to build my 160 meter inverted L antenna.   You see, Steve Silverman, Pete Juliano and I have collectively more than 150 years in ham radio, but none of us have ever operated on Top Band.  The three of us have taken A SOLEMN OATH to correct this horrendous deficiency.   I am in the vanguard, partly due to a weather pattern that is perfect for antenna building. 

Armed with a new elastic band for my Wrist-Rocket sling shot and some perfectly shaped lead sinkers,  yesterday -- with the obvious cooperation of The Radio Gods -- I managed to get two ropes over some 70 foot trees.  Soon -- with minimal gnashing of teeth -- I had 185 feet of wire in the air. 

This morning I was messing around with L networks at the base of the antenna.  I took a coffee break, leaving the 185 foot wire and the ground system connected to the coax.   I had the transmitter off, so I was surprised to see the SWR meter jumping around a bit, up significantly from zero.   What could that be?  It wasn't coming from my station, so it had to be coming from some other transmitter. And the slight bit of jumping that I saw on the SWR meter had the familiar pattern of the human voice.  Some radio sleuthing ensued.

I flipped the station antenna switch to the  "bench" position, and connected my scope to the coax.  Wow!  I immediately saw a big strong AM signal with modulation, at about  5 or 6 volts peak to peak.  The Rigol 'scope gave the frequency:  1220 kHz.  

I tuned the HQ-100 to that frequency.  As I listened to Gospel broadcast, I could follow the voice peaks on the 'scope. 

Some Googling ID's the station:  WFAX 1220 AM.   5 kilowatts in the daytime.  1.5 miles from my house.  The vertical portion of the inverted L is obviously picking up a LOT of energy from the WFAX tower.  And the horizontal portion of my antenna is broadside to the WFAX tower.

Of course this all made me think about throwing together a crystal radio, but then I realized I'd already listened to WFAX with simple diode -- the one in my SWR meter.  That little SWR meter was acting like a crystal radio with a visual output!     

Fessenden AM Broadcast, Christmas Eve 1906? Maybe not....

Garrison Keillor mentioned this in his "Writers Almanac" today. That sent me to Google where I found this: 

http://www.radioworld.com/article/fessenden-world39s-first-broadcaster/15157

But in any case, Merry Christmas to all!

Amazing Space-X Launch. Then watch the rocket COME BACK TO THE PAD

The Secret Life of Machines -- The Radio (Video)

Thanks to Rick N3FJZ for sending this to us.  In 25 minutes these fellows manage to capture and explain much of the "magic" of radio.  Great shots of Marconi, and of Hertz's first rig.  Amazing how they built their own spark transmitter and coherer receiver, launched a kite antenna and sent a signal across the harbor.  Great stuff.  Lots of history.   We've met Mr. Wells before -- he was "jailed for having the Knack!"

SolderSmoke Podcast #183 Pete's B'day, Simple-Ceivers, Binaural Bliss, 160 or Bust, GOOD BEHAVIOR, MAILBAG

Bill's Frankenstein R2 receives 7 MHz signal and generates I and Q outputs

SolderSmoke Podcast #183 is available. And it is GOOD!

http://soldersmoke.com/soldersmoke183.mp3

20 December 2015

-- Foxes in the Backyard
-- Pete completes another orbit
-- Simple-ceiver Success!
-- Frankenstein Receiver: IT IS ALIVE!  AND BINAURAL!!!
-- 160 Meter AM OR BUST!
-- Fun on 40 AM -- Lots of Multi Elmac AF-67s!  Who knew!
-- The Amateur's Code, and violations thereof.
-- Negative Frequencies? I don't think so.
-- Capacitor Offer from our Secret Benefactor: EXPANDED ELIGIBILITY
-- Projects for 2016: Pete goes Raspberry Pi, Bill goes DX-100
Mailbag:
-- Croation Creation
-- Salvadoran 2B
-- N3FJZ's Homebrew QSL
-- WA7HRG's LBS-ZIA-Simple-Ceiver Mashup Rig
-- KC0IZR turning VCRs into Mighty Mites in NOVA
-- AB1YK Starting with DC RX, going BITX
-- G8GNR puts Mighty Mite on AM!
-- G3ZPF Modulates THE SUN (Amazing)
-- VK3YE's Simple Superhet
-- Grayson in Turkey drools over KG7TR's Octalmania
-- N7REP reaches for the Zantac because of Arduinos and Surface Mount
       

Mama Mia! Mikele's Croation Simple-ceiver Video

You can just feel the homebrew enthusiasm in this video.  You can almost smell the solder smoke.

We love it when people do videos showing their new rigs spread out on the workbench with individual boards held together by bits of solder.  It is even better when, as in this video, the boards are atop hand-drawn schematic and parts-placement diagrams with much NOODLING in evidence. 

FB Mikele!  And I agree with you about the stations who call "CQ DX-only."  I used to hear that a lot when I was in Europe, and I hear it hear quite a bit too.   I always think it is a contradiction in terms. There were times when I was sitting there with a new rig, anxious to get a signal report from a strong station, and he wouldn't come back to me because of the Continent that I was sitting in! Pity.   His loss.  He might have been interested to hear about the contraption I was testing.  It could have been fun, but no, he preferred to work VK3 or Puerto Rico for the 1000th time. 

Indeed, three cheers for the legendary Pete Juliano!

Modulated Michigan Mighty Mite?

This suggestion from across the pond is a bit "out there."  In fact, for me it brought to mind the famous line from the Noel Coward song about who goes out in the mid-day sun...  This does seem like an endeavor for our stoic British cousins.  You'll need a very stiff upper lip to AM modulate a Michigan Mighty Mite!  Peter's observation about the "SSB kilowatt nerds" resonated with me and reminded me of the reaction I got when I tried to put a DSB rig on the air in London.   But hey, go for it Peter!   Please let us know the results.   For those who are rock-bound in the CW portion of the band (like 3579) this might be something fun to try using a dummy load -- just to see if you can send an AM  Mighty Mite signal across the shack.

Hi Bill,

Your recent Soldersmoke thoughts re. MMMites have been niggling my imagination; I think radio should be fun, educational, simple and cheap, to encourage young folks to get a license and "appliance users" to melt some solder.

Mike Rainey (AA1TJ) and Jim Kearman (KR1S) have done superb work in reducing RF circuits to a functional minimum... so egged on by a certain Mr. Bill Meara, I'm looking at modulating a MMMite Tx on 80m and building the simple Rx to go with it. I chose 3615kHz as it's a frequency UK VMARS (Vintage Military Amat Rad Soc) use for A.M. - the SSB kilowatt nerds who think the sky will fall down if A.M. corrupts the ionosphere have accepted a few enthusiasts firing a watt or ten of A.M. skywards. I blame you want to say thanks for setting my mind in this direction.

See how this sounds: modulate a MMM by inserting an electret mic capsule (2 terminal type) between the transistor base and ground,  not forgetting the RF choke from the electret capsule output to the base bias 10k resistor, to avoid the xtal feedback signal being absorbed in the electret...

Yep, that's it: job done, the MMM now produces A.M. as the base current, fed by 10k from the +ve rail in the original MMM, is now partially shunted to ground by the electret capsule. I'll adjust the base bias resistor to get 50% "no speech" carrier and good mod. depth. I'm trying to avoid a mic amp stage; keeps it simple & sweet. If I can get 500mW in total, that's ~ 100mW in each sideband - on a good day with a following wind, on 80m that should go a mile or twenty.

Which leaves a drop dead simple Rx to design - somebody has done similar, HERE, You got it: an LM386 audio amp as a regen Rx. I had considered the ZN414 TRF Rx, or it's modern equivalents, but they are nowhere near as common as an LM386, or as cheap. IF it works on 80m...! Or, I could try an xtal controlled regen Rx, as per Mike / Jim's designs. Either which way, I'm sure I can find a cheap, simple and effective Rx - but if you know of any.....?

Cheers Bill, TTFN!

Peter Thornton G6NGR

A Homebrew QSL Card for a Homebrew to Homebrew Contact

I got a card from Rick N3FJZ today.  FB!   Note the lines for "VFO":  Si5351!   And "Finals": Dual IRF-510s!   Rick wrote that his card is also homebrew!  Thanks Rick.

WA7HRG's LBS-ZIA-Simple-Ceiver Project

Wow Pete! 

Thanks for the GREAT info. Can't wait to try things out. One day soon (Christmas is coming) I will have a new computer and can start learning LTSpice.

Great tribal knowledge on the over all gain adjustments as well. And I won't tell the illuminati.
As for your articles, blogs, tribal knowledge and pot casts with Bill.  Love them. Listen and read everyone. Print and file for later. Mostly because I can't keep up with you on all the great projects.

But in the sprit of home brew and not just stuffing boards or following explicit directions I have built the LBS with my own mods.

1. It's dual band.  Almost. 40&20 LPF and BPF already in. 5watt tx works great but plan on putting in about 40 watts them getting around to making the dual band changes to the sketch and finishing things. I used my own audio amp design. Well not all mine. Manufacture spec sheet and Internet info and LBS. Your preamp, a NTE1288 10 watt audio IC.
Attached are pix of the LBS so far.

The current rig will be 20 meters only for digital modes. It will have a built in audio interface and thinking about including raspberry pi and TFT screen. But that's got to be down the road.
It's a hybrid again. Parts of LBS and ZIA and parts of Simpleceiver. I already had the ZIA IFs built so will have to try the dual FET on the next rig. Modified the audio again. Put in an FET AGC between the preamp and the final IC. About 40 dB dynamic range so should cut down on the vol control twisting when listening to a QSO with one strong and one weak station. So far this build consists of a box of tested modules that have not been hooked together yet. Your FET RF amp will the next board.

Also working on an Arduino Lightning detector with 5115 display. Almost got that one....   Have built couple prices of test equipment. A xtal osc with onboard freq counter and an LCR Transistor tester.

Oh and lets not forget the MMM on 3.58!

I personally know one other ham building a LBS. So don't think your talking into outer space. We are out here listening!  And learning!  And having a great time.

And yes, when I catch up on projects, I'm going to build the actual Simpleceiver.

Thanks again for the fast response. I'll let you know how it turns out.

Jim
WA7HRG

N3FJZ's New Blog and Impressive Rigs (and a Bandscan!)

Rick N3FJZ and his Lakeside direct conversion receiver bolstered my spirits when I was getting some harshly critical reviews of my signal on 40 meters a while back.  Rick happened to pick me up with his homebrew receiver. The Radio Gods seemed to be trying to balance things out.  There is a LOT of radio mojo in Rick's Lakeside receiver.  Not only does it eschew digital synthesis of the VFO signal, it goes a step further and uses a permeability tuned oscillator -- very cool.  The component and material sourcing adds more luster to the rig.  Rick writes: "A lot of the components used to construct the LS-40 were harvested from discarded consumer electronics I collected back in the 1980's. The base substrate material for the Manhattan style construction, as well as the RF tight enclosure for the PTO, is made from a flattened out tin plated food can. All components are discrete; i.e. no IC's or CPU's."

Rick has launched a blog.  He has some amazing stuff on it.  Be sure to check out his ZX-SSB rig.  Amazingly detailed documentation Rick!  Thanks. 

Find Rick's Blog here:
http://www.remmepark.com/circuit6040/

YAMMM! Yet Another Michigan Mighty Mite! From KC0ZIR in Northern Virginia

Bill,

Thank you for the podcast and the loads of tribal knowledge from you and Pete! I recently started going through the SolderSmoke backlog, and I am just getting to the Colorburst Liberation Army episodes. I had some crystals for 40m laying around, so I started reading up and winding on a film canister.

Later, I thought I'd hop up the current episode of the podcast while I work, and I heard you guys talk about another push for the Michigan Mighty Mite. I happened to be salvaging bits from an recycling-pile VCR at the time, and I came across this crystal with a familiar label: 3.579545. The radio gods have spoken, so I will be winding a new coil for 80m.

I heard you mention the anonymous benefactor, but I have some aluminum foil, and I plan to brew the cap as well, there are a few options here: http://www.instructables.com/howto/variable+capacitor/

I thought I'd tell you a quick story anyway, because I just want to be a part of the fun. When I was little, our radios all had retractable antennas, and the TVs all had rabbit ears or loops. I would spend nights trying different materials and orientations to try and get better signal. At one point, I ran as much wire as I could in my brother's room (he had a big garage-sale cabinet tv), and we were getting channels from all over the place. We knew when each channel would be showing reruns of Star Trek, so we could catch an episode or two almost every day of the week. We even got some channels that I thought were only available on satellite. I had read in my box of Popular Mechanics magazines that some dish setups re-broadcast their signal on VHF/UHF frequencies with low power, I always suspected that's what we were picking up. 

I didn't know much (or really anything) about the theory behind antennas at the time. I'm still a bit hazy, like with the 75 ohm / 50 ohm cable thing. I thought resistance was a function of length, how can different lengths of coax be the same ohm rating?

Anyway, I just wanted to let you know I'm new to homebrewing, and you guys are a big part of that!

73,

Dan, KC0ZIR

Northern Virginia (a little to the left of you, it sounds like)

..............................

Excellent Dan! 

Getting the 3.579545 MHz rock out of a dead VCR definitely adds mojo to the rig.  Indeed, TRGHS! Thanks for sharing your Knack Story.   I hope to meet up to you, perhaps at the hamfests of Northern Virginia.  In my capacity as Grand Poohbah and Arbiter of Capacitor Eligibility, I hereby deem you  ELIGIBLE for a variable capacitor.   Our secret benefactor will be contacting you.  

73  Bill   

YS1RS's Salvadoran Tuna Tin and Drake 2B

Roberto YS1RS recently acquired a Drake 2-B and has some minor tech troubles.   I am sure Alan Wolke will come up with the proper diagnosis. (The receiver works fine on the standard bands, but not on the accessory bands.  He can hear the crystal oscillator working fine on the crystal frequencies, but the radio is for some reason deaf on all the accessory bands.)  

Above you can see Roberto's Salvadoran Tuna Tin. 

 Roberto Describes it: "Homebrew: The Tuna Tin 2 QRPp Transmitter (TT2) with 300 mW output power, 14.060 MHz (20 meters band), Crystal controlled, 13 Volts, CW-Only. As its name implies, its main chassis is a Tuna Tin Can.  In our case, it is a delicious and exotic Salvadorian made tuna in chunks, topped with Jalapeño Chile. "

Check out Roberto's QRZ.com page:

http://www.qrz.com/db/ys1rs

Roberto has an amazing collection of gear, much of it thermatron, some of it homebrew.  And he has only been on the air five years.  He is a true member of the International Brotherhood of Electronic Wizards.  His work takes him to some of the most difficult places in the world.  FB Roberto! 

W7YRV: 197 feet up, on a Homebrew Tower

I talked to  Roy W7YRV on 40 SSB last night.   He was running a homebrew linear.  His blog has a lot of information on his truly massive desert antenna system.

http://w7yrv.blogspot.com/

Jean Shepherd's call signs, a QSL card, and much more

I was listening to 160 meter AM yesterday  afternoon when I heard a familiar call:  K2ORS.   I knew that someone else had picked up Jean Shepherd's last callsign, so I knew that I was not listening to a CQ from the great beyond.   Turns out that K2ORS is now OM Warren Ziegler up in Massachussets. Warren is active on HF and 160 and also works with experimental low frequency transmitters.  He is a big fan of Shep.  I think Shep would be pleased that someone who melts solder has his old call.

Searching for Warren on QRZ.com led me to a site with an amazing amount of info about Shep, his callsigns, and his early days in ham radio:

http://www.flicklives.com/index.php?pg=318

We talk about Shep quite a bit on this blog.  Here are all the Shep blog posts:

http://soldersmoke.blogspot.com/search/label/Jean%20Shepherd

Shep said that when, as a teenager, he got his ham radio license, he was so proud that he went around thinking of himseld as "W9QWN, a man of substance."  Indeed he was.

EXCELSIOR!

  

Daytime Occultation of Venus TODAY! LUNCHTIME (on East Coast)

Thanks to my Michael EI0CL for alerting us to this.  It will happen today, very conveniently at lunchtime on the East Coast of North America.  I may have to bring my Soviet binoculars to work.

Details here:  http://spaceweather.com/

It has already been a nice day for astronomy here in the wilds of Northern Virgina.  National Public Radio on Sunday alerted me to the fact that Mars is high in the pre-dawn sky.  Our friend Armand e-mailed alerting me to possible clear skies this morning.  The leaves are down and no longer obstructing my view of the Southern sky.  With my six inch telescope I got a very nice view of Jupiter and the four Galilean moons.  We are pretty far away from Mars at this point, so I could see no surface feaures, but it is always nice to see that distinctively red disk. And Venus is poised to disappear behind the moon.  

Good luck with Venus and the Moon.  Please send in reports. 

And speaking of occultations, check this one out (thanks to Farhan for the alert):

The moon passed between Nasa's Deep Space Climate Observatory and the Earth, allowing the satellite to capture this rare image of the moon's far side in full sunlight. We normally don't see this side of the moon. As the moon is tidally locked to the earth and doesn't rotate, we only ever see the one face from the earth. Awesome shot!

New Rig: The FRANKENSTEIN Phasing Receiver

Here is my latest project.  I call it The Frankenstein because of the two BNC connectors that come off the side of the DDS oscillator box -- they look to me like the bolts on Frankenstein's neck. The square waves from the DDS LO also seemed to evoke Frank's bolts. There may be other similarities.  We'll see.

Here is the idea:  Phasing,  Direct Conversion, Image Rejecting receiver based largely on the R2 design by Rick Campbell KK7B  as presented in the January 1993 QST.

I'm using an AD9850 with an M0XPD Kanga board and an Arduino to generate the quadrature LO signals (you can see the square waves on the 'scope in the background).  I'm using the software of Richard AD7C;  this, combined with the divide-by-4 scheme on the Kanga board,  puts the upper limit of reception at 7.3 MHz.  That's OK for now. 

When I first fired up my AD9850 box I was dismayed to find that the square wave quadrature output was no longer there.  I was about to give up and get anther shield board, but this kind of surrender bothered me.  So I started troubleshooting and isolated the problem to the /4 chips. My soldering of the surface mount chips was, well, a bit dodgy, so I changed to a tiny soldering tip and reheated all those tiny little pads.  Hooray!  I fixed it. 

The receiver will be built mostly on a PC board that Pete made for me back when he was trying to convince me to build a fourth BITX receiver.  I am pleased to put the board to use.   See below.

Yesterday I soldered on the two SBL-1 mixers that will form the heart of this receiver.   I realized that the very robust quadrature square waves from the Kanga board might be robust enough to fry the sensitive little SBL-1s.  Sure enough, I measured about 17 dbm coming out of the Kanga board.   I threw together two roughly 10 db resistive pads.  These should prevent the SBL-1s from releasing their smoke.     

I hope this receiver will be four receivers in one:

1) Standard DC receiver.

2) Binaural Receiver!  Groovy, stereo CW that floats around in your head,  man! 

3) I-Q receiver that can be fed into the sound card of the computer for DSP, panoramic display, etc.   I promise not use it to find fault with the signals of homebrew SSB rigs.

4) SSB image rejecting receiver for easy, Direct Conversion SSB listening without the burden of having to listen to the other side of zero beat. 

There is already a lot of soul in this new machine:  Kanga board with the design my Paul M0XPD, PC board made on Pete's $250,000 CNC machine, and all of it on an actual breadboard (from Italy, I think).  

Rick Campbell and Peter Parker have commented on the allure of phasing rigs.  There is something very attractive about them.  There is a cleverness in the way this design exploits the phase relationships between sidebands to allow us to null out the unwanted side of zero beat.  It took me a while to really understand how this is done -- once I understood it, I really wanted to build a rig that would make use of this principle.