The Ceramic Spurs (not a rock group)

Paul Taylor VK3HN's magnificent AM receiver was the inspiration for my Quarantine-31 Shortwave Broadcast receiver.  Like Paul I decided to make use of ceramic filters at 455 kHz for selectivity.  I started with the +/- 3 kHz filters that Paul used, but I found them kind of narrow for SW listening.  So I went with some wider ceramic filters that Bruce KK0S had sent me.  But I misread the specs that Bruce sent.  I thought they were 10 kHz wide filters. I realized later that they were +/- 10 kHz -- really twice as wide as I needed.  So I went back to Mini-Kits in Australia and got some +/- 6 kHz filters.  12 kc wide should be just about right, I thought. 

The bandwidth was right, but I started noticing a problem:  I could hear strong SW broadcast stations at two places on my dial.  This brought to mind an admonition from R.A Penfold, author of "Short Wave Superhet Receiver Construction" (1991 Babani Publications).   He advised keeping a few standard 455 kc IF cans in the circuit because, he warned, the ceramic filters have spurious responses, spurs that the IF cans can help knock down.  

Penfold was right.  Look at the filter response curve on the right (above).  There is a nasty spur at around 640 kHz.   This was the cause of my problem. Here is why: 

Suppose I was tuning Radio Marti's big signal on 9805 kc.  My VFO would be running at 9350 kc. 

9805-9350=455.  Great, but... 

With that spur at 640 kc, I could tune down to 9620 kc on my dial.  My VFO would be running at 9165 kc. 

9805-9165=640.  Bad.   That 640 kc difference product would make it through to my detector and AF amp.  I'd have Radio Marti showing up in two places.  I didn't like this. 

I thought about putting a series LC circuit tuned to 640 kc at the output of the ceramic filter.  This looked like a possible solution, but on the bench it looked like I would have trouble getting a circuit of sufficiently high Q.  

So rummaging around in my junk box I found an old Murata CFM455B filter.  This filter is quite broad, but it does not have the spur at 640 kc.  I could use it as a kind of roofing filter just ahead of the +/- 6 kHz filter.  Putting it there would allow me to avoid having to build additional matching circuits for the 455B filter.  

+/-6kc filter upper left,  455B wide filter to the lover right. 

I'm happy to report that this fix works.   The 6 kc filter provides the needed selectivity, and the broader 455B filter knocks down the 640 kc spur. 

Beware the Ceramic Spurs!  

Q-31 with can for first IF amps and filters open

Replacing Electrolytic Caps in my Drake 2-B (Video)

Every dark cloud has a silver lining. Here is a very small silver lining for this terrible COVID-19 situation:  I had time to do a proper replacement of the electrolytic capacitors in my Drake 2-B. 

Three cheers for Hayseed Hamfest LLC for providing the replacement capacitor.  
Go to their website to find capacitors for many other old rigs: 
http://hayseedhamfest.com 

Videos on the Q-31 Quarantine AM SW Receiver Project (and some pictures)

I've been making some short, stage-by-stage videos of my Q-31 receiver project.  So far I have seven videos.  They are here: 

https://www.youtube.com/user/M0HBR/videos

Please subscribe to my YouTube Channel.  And give me some "thumbs up" if you like the videos. 

Thanks.  SITS!  FlattenTheCurve!  73 

Pads from Pete, toroids from Farhan

The diode ring

Altoids-sized tins will hold the circuit boards

Stay In The Shack -- Or in the front yard. 

SolderSmoke Podcast #218: S-38E Woes; CW filter for uBITX; A Teensy Explosion; Mint, Cheese and Peaberries; Mailbag; A SPECIAL PLEA FOR FEEDBACK

SolderSmoke Podcast #218 is available 

http://soldersmoke.com/soldersmoke218.mp3

SolderSmoke 218 is Sponsored by AF4K Crystals: 
 Bry Carling can get you the crystals you need. 

Go to:  http://www.af4k.com/crystals.htm

Flying drones with Billy.  Amazing tech out there.  In the 50 buck range with video cameras and facial recognition and tracking.  Check out Air Pix. 

Bill's Bench: 

Active CW filter in uBITX. 

Hi-Per-Mite from 4 State QRP.  Easy to do. Works well. 

uBITX to 5 W level. 

S-38E adventure.  

Replaced antenna input coil BUT -- it came from an earlier S-38 and doesn't resonate. 

So I bought a junker on e-bay and will take the E model coil out of that one. 

Had to re-string the dial!  And add rosin to it from Maria's old violin. 

BFO was not working.  Bad buzz sound. 

So:  Re-cap, Re-tube, Re-string, Re-align, Re-build power supply.  

Shortwave sounds good.  Nice to hear music coming from our machines.  

SHAMELESS COMMERCE DIVISION:   Please use the Amazon Search Box in the upper right hand portion of the blog.

Pete's Bench

A teensy-weensie explosion and fire

Mint!  Kl7FLR

60 Meters

Cheese    Microscopes

Peaberry

Radig

California hams using online SDR receivers for local nets.  

News You Can Use!

J-310s in LTSpice

MAILBAG

K5HCT August via Regen and YouTube

Doug WB5TKI and his wife read "Us and Them."

Rich K7SZ finally following SolderSmoke Podcast.  Welcome aboard Rich. 

Rick KD4KRA  His son was one of the kids in the MIR-Classroom contact that I monitored around 1993...

David AD8Y  Read SolderSmoke Book.  Similar Knack story.  Shared 1978 story:  Homework net on 75 meters.  

Paul KL7FLR Tapping and other tribal knowledge. 

Dave K8WPE   Says I'm fortunate to have a supportive wife.  So true. 

SPECIAL REQUEST:   IT IS VERY DIFFICULT FOR US TO KNOW HOW MANY PEOPLE ARE LISTENING TO THIS.  SO PLEASE, SEND AN E-MAIL TO SOLDERSMOKE@YAHOO.COM   JUST SAY THAT YOU LISTENED TO PODCAST #218 AND TELL US HOW YOU LISTENED TO IT (ITUNES, DOWNLAD FROM BLOG, STITCHER, PODBEAN, WHATEVER...  THANKS

http://www.af4k.com/crystals.htm

PH2LB's Homebrew Hi-Per-Mite CW Filter in his uBITX

I really like the way Lex PH2LB measures and demonstrates the effectiveness of the Hi-Per-Mite CW filter designed by David Cripes NM0S.   Watch the short video above.  The blue trace is the audio input to the filter, the orange trace is the output.  Watch the output change as Lex sweeps the audio frequency range. 

He wrote: 

After studying the schematic I shifting through my spare parts stock to collected the components and build one according there design on a breadboard (I changed the center frequency from 700 to 600Hz).
I hooked up my signal generator with a amplitude of 2v max and sweeped it from 250Hz to 2KHz looking at the output on my rigol osciloscoop. On 2khz VMAX=0.04V, 885Hz=0.2V, 700Hz=1.5V, 662-585Hz=2V, 400Hz=0.2V, 500Hz=0.9V, 250Hz=0.04V. So a nice flat top between 585Hz to 662Hz.

A full description of Lex's project (with more videos) is here: 

https://www.ph2lb.nl/blog/index.php?page=ubitx-mods3#ubitx-mod14

Lex's Knack Story and the intro to his blog is here: https://www.ph2lb.nl/blog/index.php?page=history

Hi-Per-Mite Active Audio CW Filter Installed in uBITX (video)

Coming home from the Dominican Republic, this was a major item on my list of desired mods for the uBITX: a narrower passband for CW.  Using the 2.3 kHz SSB passband, you could have many CW QSOs audible in your headphones.  Narrow that passband to 200-300 Hz and life gets a lot easier. 

Farhan had discussed adding a 12 Mhz IF filter of suitable CW bandwidth, but this seemed difficult to me. Besides, I have long wanted to use an active audio filter for this purpose. 

The Hi-Per-Mite filter from 4 State QRP Group is just what I needed. I built the kit without problems in about an hour, then I put it in the uBITX box, with  switch on the front panel that lets me put it in the circuit or take it out -- this is very satisfying and a lot of fun.  

The Hi-Per-Mite just goes between the uBITX audio out and the speaker/headphone connection. I built mine for "no gain" -- the uBITX provides plenty of audio. 

The selectivity with the Hi-Per-Mite compares favorably to that of my Drake 2-B with the 500 Hz LC filter.  You can get an idea of the performance in the video. 

Three cheers for the 4 State QRP Group and their Hi-Per-Mite!  Here is the page with all the info: 

http://www.4sqrp.com/hipermite.php

Antuino Filter Analysis

Farhan had given me one of the early Dayton Hamvention models of the Antuino SWR/PWR/SNA RF test lab.  He later identified the need for a few mods to improve performance on that early model.  So I brushed up on my surface mount soldering, got the needed (tiny!) parts and made the mods.  I also put the battery pack inside the box and put some feet on the Antuino cabinet (it just seemed like the right thing to do). 

Antuino has already proven to be very useful as an SWR analyzer.  I know have a much better understanding of the SWR bandwidth of my wire antennas. 

And it is very useful in evaluating the passbands of filters.  I had an old 11.273 MHz filter from an old CB radio in my junk box.  I have no specs on this device -- I didn't know what impedances it was designed for.   So it was time for some Antuino technical detective work. 

First, take a look at the filter with nothing between it and the Antuino.  Input and output on the Antuino are 50 ohms, so here is what the passband looked like with 50 ohms: 

Next I put in two 47 ohm resistors, one in series with the input, the other in series with the output.  Antuino connected at the other side of each resistor.  Here is what it looked like.  Note the improvement in skirt shape.  But there is still a lot of ripple in the passband: 

Then I went to 100 ohms.   The passband ripple was reduced noticeably: 

Then up to 330 ohms.  Here the passband doesn't seem quite as flat as it was with 100 ohms: 

Finally, 1000 ohms.  Definitely too much.  Note the ripple. 

 

Farhan prefers the passband with the 100 ohm resistors.  I agree.  

BTW the filter is from TEW of Tokyo, Japan.  Model FEC-113-2  11.2735 MHz  No. 2   A    2

It had three crystals on the board with it:  11.275 and 11.272 -- these are obviously for LSB and USB.    The third crystal is at 11.730 MHz, indicating to me that they had a second IF of 455 kHz in this rig.   If I use it, I think I'd stay with single conversion. At 11.273 MHz the filter is of ideal passband width for SSB.  I do feel the urge to build something around this filter. 

Doing the mods on the Antuino was fun, and having worked on the device at least a little bit I feel more of a connection to it. 

VK3HN's Inspirational AM Receiver (video)

I'm always delighted when I check the SolderSmoke blog and YouTube list (right hand column of the blog) and find a new post from Paul VK3HN.  And this morning's post is especially good. 

Paul has built an AM receiver. Above you can see his video.  Here is his blog post with details: 
https://vk3hn.wordpress.com/2019/12/06/8-band-superhet-am-receiver/

This is the kind of blog post that makes you want to heat up the soldering iron and start searching through the junk box.  I'm thinking about putting Paul's 6 kHz filter in my 40 meter HRO-ish receiver.  And I may make use of his AM detector circuit.  And maybe I can put that same receiver on 75 and 160... And then there are the SW broadcast bands... See what I mean?  

Thanks Paul.  73  

SolderSmoke Podcast #214 is FINALLY out!

WE ARE WORKING TO IMPROVE THE AUDIO QUALITY.  IN THE FIRST RELEASE OF THIS PODCAST SOME OF THE AUDIO WAS KIND OF MUFFLED.  I TRIED TO FIX IT THIS MORNING AND I THINK I MADE SOME IMPROVEMENTS.  THE IMPROVED AUDIO IS NOW AT THE LINK BELOW.  

4 November 2019 (shockingly late!)

http://soldersmoke.com/soldersmoke214.mp3

The visit of Farhan to Northern Virginia
"I heard this guy from Southern California on 20..."
Fire Report from Pete

Pete's Bench Report
"When you know stuff, you can do stuff!" 
The CRAP rigs 
Old Boatanchors -- the Swan 120  with SUPER STABLE ANALOG VFO! 
Ten Tec rigs dial cord replaced with Chinese digi sig counter 
Pete's 500 mW encounter with a QRO curmudgeon
The ZL2BMI Challenge has Pete building crystal filters
The Left Coast Loafer CW rig 

Bill's Bench Report

ET-2 Refinements
N0WVA's Regen Receiver 
Going from ET-1 to ET-2
J-310s vice MPF-102
100 mW from a single J-310
Receiver kind of deaf -103 dbm MDS
10 contacts so far in 9 states 
THREE contacts yesterday.
Worked Wisconsin - 633 miles on 92 mW 
We are at sunspot minimum. 
"Rage, rage against the dying of the light." 
Simplicity is the real reason for CW 

IDEA:  Get those Michigan Might Mites on the air! 
Use Reverse Beacon Network to see if you are getting out 
Use SDR receivers to make contacts

MAILBAG
DL1AJG
KC6SAX
W9VNE
KA4KXX
N0WVA
Zl2BMI
AJ6BD  

The Collins Mechanical Filter -- An Advertisement from Australia, 1963

Peter VK2EMU sent me this ad a while back.  He said he regretted being unable to send a filter -- all he could send was the ad.  Thanks Peter -- I think that ad is a work of art.  Radio art. 

Thanks too to all those who sent me mechanical filters.  Pete sent the first one (it is currently in my HRO-ish receiver), then two more (both inside SBE transceivers, where they will remain -- it would be a sin to cannibalize those beautiful rigs.)  Then Mike Herr WA6ARA sent one as did Brad.    Brad assures me that the one he sent was boxed up by Art Collins himself! 

Thanks again guys. 

Brad wrote: 

To:soldersmoke@yahoo.com

Jun 23 at 7:49 AM

Kudos to Pete for 60 years! And I've always thought he was much younger than you......

Catching up on your podcast, I was surprised to learn that no one answered your call for a spare filter.  

I'm one of those older guys who is making his way back after leaving amateur radio in 1968 for girls and/or recreational drugs.

No one told me that The Force (electro-motive, that is) would require me to catch up on all the junk I would have acquired during my nearly 50 years away from the hobby (see list below).

A recent impulse purchase, the most beautiful thing with tubes ever made (SX-42), happened to be near Newington.  On the way home I visited ARRL HQ hoping they had some sort of a chapel where I could perform an act of penance and ask for guidance in dealing with my affliction.   Apparently, this is the equivalent of asking a crack dealer where the closest Narcotics Anonymous meeting is held. I ended up buying a copy of "200 Meters and Down" and have since acquired a couple of Atwater Kent projects. 

My place is full now, and my sweetheart would like back the half of her garage I've slowly taken by electronic eminent domain.   It seems that for every 100 pounds that departs to a ham fest, 125 pounds comes back.  Is this considered a normal ratio?

In order to be able to tell her that I have, indeed, gotten rid of something, I'll be sending you a F 455 filter (QRZ address OK?).

Thanks for you help,

--Brad 

W4AMV's Beautiful Receiver

Hi Guys,

We had our Knightlites annual BBQ this past Saturday. I wanted to share one of the radios from one of my Elmer's, Alan Victor W4AMV.
Pictured is him standing beside the preselector and receiver.
I hadn't ever heard a Collins mechanical filter vs Murata crystal filter side by side. The Collins was amazing. Single signal extracted from the band. The rig is line powered with a built in power supply.
There is a note (pictured) that has some specs.
Alan's work is to be savored, true analog engineering at its best. I wanted to share it with you.

Chris
KD4PBJ

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

FROM W4AMV'S QRZ.COM PAGE:

Here is a receiver that started out as a regen for the grandkids to copy code.

Digging through the junk box un convered parts that I forgot I had. Included a wide and narrow band set of filters. So, the unit wound up as a single conversion superhet. A fun radio to build as well to listen. The wide band filter provides super fidelity on sideband as well uncovers plenty of CW signals within a 10 kHz bandwith of the tuned frequency. A switch to either a 800 Hz audio filter or a 500 Hz CW filter permits focus on a single signal. I was going to package the whole unit, however I was prompted to leave it OPEN to show what makes it tick! 

Left side front is the RF preselector, mixer and pre amplifier with RF gain control. The rear double deck card is the IF and selectable wide and narrow band filters. The IF and pin diode IF gain control is bottom deck. The HF VFO is center stage with a 6:1 gear reduction. Right rear is power supply and voltage regulators. The active product detector and a BFO is just to the front of the power supply. The BFO is able to tune product detector output over a full 10 kHz of the IF. And finally the audio filter and 5 watt power amplifier. There is no AGC. Instead it is FUN to control every aspect of  gain control of the receiver; RF, IF and audio. Its a fun receiver to operate, dedicated to 40 meters and hopefully will spark the kids! 

Going forward a receiveing station is setup to copy code. Although a nice long high wire would be proper, I settled on something a little more compact. A 40 meter small loop, 2 turns, about 18 inches on a side is connected to the preselector thru a pickup wire. This arrangement works quite well. W1AW will knock the speaker off the desk if your not careful. However, rotation of the loop to the E-W knocks down W1AW to a whisper. The pix shows the little 25 W infinity speaker in a 8x8x8 inch cardboard box, works well and the single conversion receiver sporting a new front plexiglass panel is illuminated for evening tuning. 

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

Loop antenna used with the receiver

A Beautiful Variable Capacitor (from Pete)

Is this a thing of beauty, or what?   Pete sent this to me back when I was having trouble finding a "smooth running" variable cap for my HRO dial receiver.  It has a standard Jackson Brother's reduction drive attached to the shaft, followed by a really cool gear arrangement.  Note the spring loaded teeth on the big gear -- that is to keep the gears tight when turning in both directions.  

As was the case with the HRO dial that Armand sent me, the beauty of this part will cause me to build something with it, really just for the purpose of putting it to use. We've been talking about double or triple conversion superhets with 100 or 50 kHz final IFs.  At those frequencies you can get good selectivity with LC filters.  As with the Drake 2-B.    Steve N8NM is sending me a dial that will go well with this part.  That will add to the already abundant mojo/juju.  I feel a VFO in the works.    Thanks to Pete for being so supportive of my luddite analogism.  

DISAPPOINTED! No Takers on Mechanical Filter Question! SAD!

So, in our last podcast I asked the group to take a look at two pictures of a mechanical filter that I had recently taken out of its case.   These pictures appear above and below. After a discussion of magnetostriction,  I asked the group if they could spot anything unusual about this particular device. 

I expected many responses.  What did I get?  CRICKETS!!  What is wrong with you guys?  Are you spending so much time with software and FT-8 and lines of code that you can't deal with a simple analog question like this?  SAD! I guess I will have to answer the question myself.  Scroll down. 

The diagram below presents the conventional Collins arrangement for a mechanical filter.   Note that at the input and at the output there is a coil.  This coil creates from the signal a varying magnetic field.  Because of the principle of magnetostriction, this field causes the resonators/rod assembly to flex and vibrate, much like a musical tuning fork.  At the output, this means that inside the core of the output coil there is a piece of metal vibrating at the signal frequency.  This will produce an output signal.  

But take a look at my little mechanical resonator.  Where are the input and output coils?  

THERE ARE NONE!  See those little rectangular things at either end?  Those are piezo-electric crystals that are MECHANICALLY connected to the disc/rod assembly.  So when the signal comes in, it is applied electrically to the piezo material which then physically vibrates. This vibration passes through the filter and to the piezo device at the other end. There the mechanical vibration results in an electrical signal at the output.  

So, I think it is time for you all to hang your heads in shame. Perhaps go to the doctor to see if you still have The Knack. Ask for forgiveness from the radio gods.  

SolderSmoke Podcast #210 Boatanchors, Magnetostriction, VFOs, AM, CW, SSB, Mailbag

2 March 2019 

SolderSmoke Podcast #210 is available: 

http://soldersmoke.com/soldersmoke210.mp3

Alexa, Marie Kondo, berets, and ham radio

Bi-Coastal Boatanchors
BATTLE CRY: The Vintage SSB Preamble! "We are NOT ashamed!" 
Bill's HT37 and Drake 2B 
Pete's National National NCX-3  TRGHS
Mechanical Filters
Magnetostriction
Why did Collins go with mechanical vice crystal filters? 
The foam deterioration syndrome in mechanical filters.  Sad. 
Please send any unwanted Mechanical Filters to Bill. 
BONUS QUESTION:   Look at the filter below.  What is different/special about this one?

Pete's antenna trouble
Pete's FB amplifier troubleshooting
Recent improvements in the uBITX finals
Pete's design for a VFO for Bill (and an indoor antenna tuner!)

Bill's VFO for Pete:  HRO dial and gearbox driving a rotary encoder

Guido PE1NNZ puts the QCX on SSB
"The Secret Life of Machines -- Radio"
HB HRO dial from DL6WD
WA1QIX's USB D-104
"The High Frequency Oracle" 
DeMaw's LC filter receiver
Godzilla and Ham Radio
Bill's poor quality SSTV images from space (what happened?) 
Listening to AM on an SSB receiver
Mixed feelings about CW 

MAILBAG
M0KOV's mom took him to the doctor due to THE KNACK. 
M0JGH getting married (ALWAYS LISTEN TO PETE!) 
Jac's FB Receiver

What is different/special about this one?

Pete's Latest SSB Transceiver -- And Lots of Wisdom on Homebrew Phone

Don't miss Pete's latest blog post decribing his most recent SSB transceiver.  

http://n6qw.blogspot.com/2019/02/2019-building-ssb-transceivers.html

Switching to a Mechanical Filter from 1967 for my HRO-ish Receiver (with video)

From RSGB Handbook 1982

Having overcome the difficulties with the National NPW Dial and Gearbox, I turned my attention to the 455 kHz filter.  I had been using this old Toyo CM - 455 kc filter (Date stamped August 1969).  CM stands for "Crystal-Mechanical."  These filters are hybrid with some of the features of a crystal filter and some of the features of a mechanical filter. For more details go here: 
https://soldersmoke.blogspot.com/2016/04/the-meaning-of-cm-in-toyo-cm-455-filter.html

I was disappointed by the CM filter.  It seemed very lossey, and it just didn't seem to be of sufficiently high Q -- it seemed very broad. I could hear the other side of zero beat.  It was barely a "single signal" receiver,  and being "single signal" is the whole point of a superhet. 

I remembered that Pete Juliano had sent me a Japanese-made 455 kc mechanical filter. Maybe this would do better.  Last night I did a quick comparison test and -- wow -- Pete's filter was much better.  The Fifth Edition of the RSGB Handbook seems to agree with my assessment, noting that mechanical resonator filters were superior to the Crystal Mechanical hybrids (see pages 4.17 and 4.18) 

Pete's filter is from the Kokusai Electric Company.   Part# MF 455 ZL.  (Date stamped May 1967). "ZL"indicates lower sideband.   I checked and indeed the passband goes from just above 452 kc up to about 454.5 kc.  This is a 40 meter receiver and SSB on 40 is LSB, so this filter would work perfectly right?  Not so fast!  Sideband inversion had to be considered.  

I was running my VFO from about 7455 to 7755 kHz.  This means that the modulated incoming signal would be SUBTRACTED FROM the VFO signal to get to  the 455 kHZ IF.  And when that knd of subtraction happens, we have sideband inversion.  The LSB signal will look like a USB signal when it reaches the filter. 

My BFO was running right at 455 kHz, using a ceramic resonator at that frequency. I briefly considered just shifting it down to 452 kHz, but this proved to be difficult.  Then I got a better idea. 

I could just shift the VFO down to 6545 to 6845 kHz.  This would mean that the VFO frequency would be subtracted from the incoming modulated frequency.  There would be no sideband inversion.  I had been thinking about doing this frequency shift anyway, thinking that VFO stability gets better as you go lower in frequency. 

REMEMBER THE RULE:  If you are subtracting the modulated (signal) frequency from the frequency of the local oscillator or VFO, only then will you have sideband inversion.  See: 
https://soldersmoke.blogspot.com/2015/05/sideband-inversion.html

Moving the VFO was easy. I am using a variable capacitor with several variable caps on the same rotor.  I just moved from the smallest variable cap to the middle variable cap -- this added capacitance to the system and lowered the frequency.   I also added three additional turns on the coil.  This put me very close to where I needed the frequency to be.  I added one additional 9 pf cap and this put the VFO freq right where I wanted it. 

I was really  glad to include Pete's filter in this receiver.   The mechanical resonator technology fits very well with the very mechanical old-tech theme of this project (it already had a gearbox -- a mechanical filter seemed to fit right in).   It is a fascinating device -- it is almost like having a set of tuning forks all tuned to 455 kc (see above for the RSGB description of how it works).    And having it from from Pete adds a TREMENDOUS amount of mojo, juju, and soul to the new machine. 

Icing on the cake: As I type this, I am listening to Fred K3ZO converse in Spanish with hams all through South America.  Fred preceded me by three decades at the U.S. Embassy in Santo Domingo, but when I got there the local hams were still talking about him  -- he was much loved and admired by the Dominican hams.  TRGHS. See Fred's story here (scroll down a bit): http://www.gadgeteer.us/DRDISP.HTM 

Built-in Spectrum Analyzer in Hans Summers' QSX Rig.

I agree completely with the e-mojis.   Wow!  Cool!  I love it! 

Hans Summers is a genius. 

This is almost enough to make me get with the program and embrace SDR.  

Hans has done what seemed to have been impossible: true homebrew with SDR. 

SolderSmoke Podcast #203 Winter, Transceivers, Antennas, DC RX, uBITX, Mixers, 'fests, MAILBAG

N6QW in 1959. Building an SSB transceiver

SolderSmoke Pocast #203 is (FINALLY!) available: 

http://soldersmoke.com/soldersmoke203.mp3

24 March 2018

--The reasons for our delay. 
Winter, Computers, College, Family Trees, Lawyers....

-- Winterfest 2018 
-- Pete launches 2018    THE YEAR OF THE TRANSCEIVER
    http://n6qw.blogspot.com/
-- SDR -  Satan's Digital Radio?  
-- Direct Conversion Receiver Projects
-- Mixer Musings 
-- A Thailand Troubleshoot 
-- Nor'Easter knocks out Bill's Moxon -- An appliance replacement? 
-- Homebrew Electret Mics.  Seriously.  
-- uBITX Build with Rogier
-- Civilized Crystal Testing
-- Baofeng! 
-- DRAGNET

-- MAILBAG
KD4PBJ's REGEN 
N6ORS's SDR rig
Mike Rainey's DX-100

Great Video on Crystal Motional Parameter Measurement

Who out there can save us from further Dishal distress?  Who has one of these fantastic bits of old test gear and is willing to donate it to the cause of accurate filter building?  

Thanks to Tore LB4RG for alerting us to this gem.  

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

Bill Breshears WC3K (SK)

SolderSmoke Podcast #198 is available. 

http://soldersmoke.com/soldersmoke198.mp3

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.