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Showing posts with label GQRP. Show all posts
Showing posts with label GQRP. Show all posts

Wednesday, April 3, 2024

Ian Keyser G3ROO and Spy Radios


Above is a recent ICQ podcast interview with Ian. 


This sojoun into spy land started with this WTF video: https://www.youtube.com/watch?v=4f3ZJYdmpZw

Crypto Museum explains what the Mk 301 was all about:  https://www.cryptomuseum.com/spy/mk301/index.htm

 I have had Ian on the SolderSmoke blog several times: https://soldersmoke.blogspot.com/search?q=%22Ian+Keyser%22

N2CQR at the key with a G3ROO paraset

Wednesday, April 26, 2023

Retro QRP Rigs of the 1960's, 70's, and 80's -- Video by Mike WU2D


It is time to put aside (again!) all of the heated ideological arguments about the power level that defines "low power."  Just sit back and enjoy this wonderful trip down QRP memory lane. 

Mike's description of the simple, single-transistor QRP transmitter was really nice.   I recently made something similar: https://soldersmoke.blogspot.com/2023/02/first-qso-with-high-school-receiver-100.html  And Mike does a nice plug for our beloved Michigan Mighty Mite.  Go CBLA! 

The modular idea:  words to live by my friends. 

40673!  TT2!  And G3RJV's PW Severn - indeed, bow your heads!

Wow, the Ten Tec Power Mite (or Might!) -- I still want one.  Same for the Argonaut -- what a great name (sounds like a "magic carpet), and with SSB to boot!  I want to join the Argonaut cult! 

I have both the HW-7 and HW-8 (the HW-8 is heading to the Dominican Republic).  This video makes me want to fire up the HW-7.  Maybe on 40.  

My 40 meter homebrew rig (Digi-Tia) has in it the filter from that old Yaesu FT-7 rig.  The filter was given to me by Steve "Snort Rosin" Smith.  https://soldersmoke.blogspot.com/2015/05/bitx-digi-tia-build-update-2-installing.html  


Thanks to Mike for including me in the credit roll at the end.  What a great group of people -- it is a real honor to be listed with those folks. 

Tuesday, September 13, 2022

Great Technical Info and Tribal Knowledge from GQRP

Thanks to Tony Fishpool G4WIF for sending us this link.  

https://www.gqrp.com/tech.htm

There is a lot of great tech info and Tribal Knowledge on the GQRP page.  This is all related to our discussion of how to set up an electronic workbench or workshop. 

Thanks Tony and thanks to GQRP. 

Friday, August 5, 2022

SolderSmoke Podcast #239: Hex DX, VFO Temp Comp, DC RX, Polyakov!, DX-100, Wireless Set, Farhan's "Daylight Again" HDR rig, MAILBAG

N2CQR Hex Beam Aimed at Europe

SolderSmoke #239 is available for download: 

http://soldersmoke.com/soldersmoke239.mp3

TRAVELOGUE: 

James Webb Space Telescope.  Mars returning to opposition in early December.   

BILL'S BENCH

Hex Beam K4KIO - on roof – TV Rotor – 20-17-12  Lots of fun.  Working Japan regularly, Australia, South Africa on long path 17,000 miles.  52 countries SSB since July 11.

VFOs and Temp stabilization.  Dean KK4DAS found my ceramic resonator VFO for DC receiver drifty. He was right.  So I built a real LC Colpitts VFO.  Got me into temp stabilization.  A new hobby!  An obsession.  HT-37 and Ht-32 parts. Ovens?  WU2D’s second VFO video.  Understanding thermal drift and how to address it. Split stator caps.  Cut and try.  

Built a Polyakov DC Receiver. https://soldersmoke.blogspot.com/2010/03/polyakov-plus-dual-band-receiver-with.html  Lauser Plus.  Lauser = Imp or Young Rascal!  DK2RS.  He used a ceramic Resonator VXO at 3.58 MHz.   Mine works great on 40 with VFO running 3.5 -- 3.65 MHz. See schematic below. 

On 40 AM with DX-100 and MMMRX.  DX-100 died.  12BY7 VFO buffer went bad.  How common is failure in this tube type?  Nice QSO with Tim WA1HLR about the DX-100.

Got my Dominican license:  HI7/N2CQR!  SSSS on the way.   Thanks to Radio Club Dominicano and INDOTEL.

Getting more active in the Vienna Wireless Society.  

BOOK REVIEW:  

"The History of the Universe in 21 Stars” by Giles Sparrow.  Written during the pandemic.  Published by Welbeck, in London. https://www.amazon.com/History-Universe-21-Stars-imposters/dp/1787394654  Also:  From “Atoms to Amperes” by F.A. Wilson available for download.  See blog.

SHAMELESS COMMERCE DIVISION:   

Todd K7TFC getting ready to launch “Mostly DIY RF.”   I used his TIA boards in my 1712 rig.  He will have boards like this and much more.  Stay tuned.

I need more viewers on YouTube.  They want 4,000 hours IN A CALENDAR YEAR!  Please watch!

FARHAN’S NEW “DAYLIGHT AGAIN” RIG.  Analog.  VFO.   Comments, observations. We need to get him on the podcast.  Maybe two shows: SDR and HDR. 

PETE'S BENCH

Time very limited. But still sharing lots of tribal wisdom.

Wireless set with tubes!

Tool recommendation – Air compressor

 MAILBAG:

Farhan VU2ESE – Speaking of big antennas “Whenever I look at the huge construction cranes in Hyderabad, I always think how one could make 160m, 4 element yagi using it as a boom..

Todd K7TFC in Spain, spotting Log Periodics in Madrid.

Andreas DL1AJG:  Can Biologists fix Radios?

Janis AB2RA Wireless Girl.  Expert on Hammarlunds.  And was my first contact with the Tuna Tin 2. She too was HB!

Peter Parker VK3YE on Owen Duffy VK1OD

Lex PH2LB on homebrew radio

Would this really be homebrew?  Mail from H-A-D article on FM receiver

F4IET a DSB rig from France

Ciprian got his ticket YO6DXE    

Josh G3MOT sent us a good video about the Vanguard satellite and IGY.

Dave Wilcox K8WPE bought Chuck Penson’s Heathkit book.

Rogier -- So many great articles and links from PA1ZZ

Bill AH6FC  Aloha. Retiring.  Wants to build.  Mahalo!

Grayson KJ7UM  Working on an Si5351.  Gasp.

Mike KE0TPE viewing YouTube while monitoring 6 meters.   He will have a lot of time to watch!

Chris KD4PBJ spotted Don KM4UDX from VWS FB

Mark WB8YMV building a superhet.  Having trouble with 455 kc IF can filter.

Walter KA4KXX Great comment on the Daylight Again rig. 

Ramakrishnan Now VU2JXN was VU3RDD.  Found lost Kindle with SolderSmoke book on it. Building SDR rig from junk box.  Trouble with the LM386. 

Pete, Farhan and Tony:  Shelves of Shame

Daylight Again by Farhan

The Polyakov receiver I built yesterday (from SPRAT 110, 2002!)

Wednesday, October 13, 2021

SolderSmoke Podcast #233: PIMP, Boatanchors, Novices, MMM, Heathkits, DC Receivers, Mailbag


SolderSmoke Podcast #233 is available. 

http://soldersmoke.com/soldersmoke233.mp3

Travelogue: Cape Cod. SST. Marconi Site.

The WFSRA:   The World Friendship Society of Radio Amateurs.


Pete's Bench:

The Pimp.
The NCX rig.
The Collins.
The many DC receivers built worldwide.
The parts shortages are real! Several key radios on hold. Si5351 sub.
Talk to G-QRP convention

Bill's Bench:

FT-8. Not for me. I tried it.
Novice Station Rebuild.
Globe V-10 VFO Deluxe.
Selenium rectifier removal CONTROVERSY?
Not crazy about my Novice station. Not crazy about CW. 
Mate for the Mighty Midget. Again. 
Mike W6MAB -- Detector problems LTSPICE Check
One more mod for MMM RX. Ceramic filter at 455.
Dropped screw inside tubular cap on Millen 61455 transformer. 
Talk to the Vienna Wireless Society
Thinking of a Moxon or a Hex beam.


BOOK REVIEW Chuck Penson WA7ZZE New Heathkit Book. http://wa7zze.com


Mailbag

-- New SPRAT is out! Hooray!
-- Todd K7TFC sent me copy of Shopcraft as Soulcraft. FB.
-- Dean KK4DAS building an EI9GQ 16 W amp. FB.
-- Jack NG2E Getting close on Pete's DC receiver.
-- JF1OZL's website is BACK!
-- Tony K3DY sent link to cool books. 
-- Sheldon VK2XZS thinking of building a phasing receiver.
-- Peter VK2EMU has joined the WFSRA. FB!
-- Ned KH7JJ from Honolulu spotted the Sideband Myth in the AWA video.
-- Chris M0LGX looking at the ET-2, asks about the variometer.
-- Pete Eaton Nov 64 anti HB rant in november 1964 QST. Wow.
-- Josh Lambert Hurley spreading FMLA stickers in the UK. FB
-- Stephen VE6STA getting ready to melt solder.
-- Got a great picture of Rogier PA1ZZ back on Bonaire.
-- Farhan reading the manual of Hans's new digital rig.
-- Paul G0OER wonders if FMLA getting ready to move on 5 meters.

Friday, August 27, 2021

SolderSmoke Podcast #232 -- Mythbuster, Pete's Tube CW Rig, Pete's DC RX and Simple SSB Rig, NanoVNA and TinySA, Very FB Mailbag


SolderSmoke Podcast #232 is available -- Crank it in Robert!


Featuring a guitar intro by Pete "Bluesman" Juliano,  playing his own composition: "Juliano Blues." 

Upcoming GQRP convention and the N6QW rig
Frank Jones and the FMLA -- Possible Victory?
IBEW Stickers:  NASA, Johns Hopkins APL....
Cycle 25 Lookin Better Today:  SFI 93   SN 47
 
Pete's Bench:
Toobular!  A Tube Transmitter
SR-160
Simple SSB rigs around the world! 
KI7NSS's Pacific 40
 
Bill's Bench
The Mythbuster and the Struggle Against the Urban Legend
W2EWL's Cheap and Easy SSB
W4IMP's IMP. Articles in ER by Jim Musgrove K5BZH and Jim Hanlon W8KGI
The Spirit of Homebrew SSB. From Electric Radio K5BZH December 1991
Reduced Front End Gain on the DIGITIA
Back on 17!  HP3SS sells HBR receiver to Joe Walsh
Maybe another Moxon?
 
SHAMELESS COMMERCE DIVISION
 
Test Gear
NanoVNA -- Alan W2AEW helped solve mystery of why NanoVNA not providing accurate readout of circuit impedance.  Over driving.  Need attenuator. 
TinySA -- Limited Resolution Bandwidth.  But you can listen with it!  See video on blog.
 
MAILBAG
-- Google Feedburner to end e-mails from the blog :-(
-- Paul VK3HN -- TIA AGC? Farhan and Paul looking into options 
-- Ciprian's Romanian Mighty Mite
-- Dino KL0S SolderSmoke GIF and graphical presentation on sideband inversion
-- Allison KB1GMX helped me on 24 volts to IRF 510 issue.
-- Dave K8WPE Wabi Sabi and Martha Stewart. And thanks for parts!  40673s!
-- Steve N8NM building a 17 meter rig with 22.1184 crystals in a SuperVXO and a 4 MHz filter.  
-- Dean KK4DAS restoring an old Zenith.  One hand behind your back OM. 
-- Pete Eaton debating SSB or DSB for 17.  Go DSB Pete!
-- Richard KN7FSZ a FB HBer.  Asked about my solid-stating of Galaxy V VFO.  
-- Walter KA4KXX on benefits of no-tune BP filters like Farhan's   FB. 
-- Jack 5B4APL on Time Crystals and Homebrewing in the 4th dimension.  FB OM!  
-- Moses K8TIY listens to the podcast with his young son Robert.  Crank it in Robert! 
-- Farhan and the SBitx on Hack-A-Day
-- Also Tom's receiver from junked satellite rig on Hack-A-Day
-- Todd K7TFC sent in beautiful message about the spirit of homebrewing. On the blog.
-- Grayson KJ7UM was on Ham Radio Workbench with George Zaf
-- AAron K5ATG running a uBitx with a  homebrew tuner and antenna.  Hope I can work him 
-- Heard Mike WA3O last night on 40 DIGITIA.  Water cooled amplifier

Thursday, August 12, 2021

Grayson Evans KJ7UM on the Ham Radio Workbench Podcast

 
OM Grayson was on the HRWB podcast with George Zaf and company. This was a really informative and entertaining session.  For example, when asked if special precautions are needed when working with thermatrons, Grayson replies, "Well, try not to swallow anything... and don't sit on the thermatrons."  Words to live by my friends.  Grayson's story about cooking Tektronix scopes in a refrigerator re-purposed as an oven (after cleaning the 'scope with a Home Depot power washer) is the kind of practical advice that readers of this blog REALLY NEED!  

But seriously, I learned a lot just listening to Grayson talk about thermatrons with George and the HRWB crew.  

The interview includes nice shout-outs to SolderSmoke, SPRAT/G-QRP, and Electric Radio magazine. 


Stay to the end for some thermatron-related password management advice from George. 

Thanks to Grayson and to all the folks at HRWB. 

Tuesday, January 12, 2021

Pete N6QW and Steve G0FUW Talk to RSGB About Homebrew (Video)


Wow, what an unexpected treat!  Here we can watch Pete N6QW and Steve G0FUW talk to the Radio Society of Great Britain about homebrew radio.  Steve talks about kits and scratch-built rigs.  I really liked seeing his early rigs and his description of how building these rigs helped him become a more advanced homebrewer.  I also liked his mention of George Dobbs as a guiding light in the QRP and homebrew world. 

Pete focuses on SDR and provides a really great description of this approach to homebrew.  I was struck with how great it is that, after a lifetime of HDR building, Pete is willing to embrace this new technology. He talks about it as part of "a learning journey."  As always, he sets the example for us all.   

Thanks to Pete, Steve, and RSGB. 

Thursday, December 10, 2020

Pete Juliano's Presentation to the 2020 G-QRP Club Convention -- Building SSB Transceivers


It is a great day my friends.  G-QRP has posted on YouTube the presentations made at their 2020 convention. TRGHS! Above you can see the awesome FB contribution of Pete Juliano N6QW.  I watched it live on Zoom, but have been waiting patiently for the opportunity to share it with SolderSmoke readers and listeners. 

There are many other great videos of convention presentations on the G-QRP YouTube channel.  Here is the link to the channel: 
Be sure to subscribe and give many "thumbs up" to the presentations. 

I see that our friend Alan Wolke W2AEW has a presentation on the NanoVNA in that channel. FB Alan. 

Thanks to G-QRP for running this event and for putting these videos on YouTube. 

Saturday, September 19, 2020

SolderSmoke Podcast #225: Mars, uSDX, G-QRP, HP8640B, DX-390, Rotary Tools, Walla Walla SDR, MAILBAG

SolderSmoke Podcast #225 is available

http://soldersmoke.com/soldersmoke225.mp3

Mars,  West Coast smoke.

Pete's Activities: 
-- DC receivers.
-- CW offset
-- GQRP talk
-- The uSDX project

Bill's Bench
-- Sliding into the Vintage Test Gear Cult:  HP8640B . 
-- Fixing up and figuring out Radio Shack DX-390 receivers.  
-- 220 to 110 on a few remaining devices.     
-- Got myself a Dremel-like rotary device.  

Tech News: 
-- ARRL/TAPR Convention:  SDR project from Walla Walla University students.   Intuitive explanation for why desired and image freqs in a mixer come out with very useful phase differences.  

-- Chuck Adams' Amazing Lab Notebook.   Includes a simple circuit to measure resistance and Q in crystals.  FB. 

MAILBAG: 

-- Dino KL0S  SITSing in his shack, homebrewing 9 MHz filters  FB Dino.  Airborne! 
-- Dave NT1U sent us the famous 1968 QST Article by W7ZOI re DC RX.  
-- Ron K0EIA listening to SWBC staions with uBITX.  
-- Ted AJ8T  Korguntubes making a 12AX7 equivalent.  
-- Joel N6ALT sent me a nice DX-390 manual.  Thanks Joel
-- Bob KD8CGH alerted us to the uSDX project -- story on the blog. 
-- Craig AA0ZZ Sent a great message with insights on computer code -- I will put up on the blog. 
--Tracy KN4FHX reports on optimistic prognosis for SolarCycle 25.  Some chickens may have to be sacrificed.   
-- Stephen M0OMO Thanks SolderSmoke for rekindling interest in this hobby. 
-- Paul VK3HN  has a cool new rig -- The Prowler -- check it out
-- Steve N8NM working on his Sunbeam car -- Pete already knew about the carburetor synch problem.  N6QW knows everything. 









Saturday, November 9, 2019

SPRAT, the FETer, DLR headphones, and recent QSOs on the ET-2


Yesterday we had QSO #13 on the ET-2.  This was with Jim W1PID.  In an earlier contact Jim told me I had some chirp.  I fiddled with the coupling cap and the bias pot and am now T9!  These days, chirp is an endearing, nostalgic problem to have.  Thanks for the report and QSOs Jim! 

Contact #9 was with Fred K9SO.  He is in Wisconsin and QRZ.com put our distance at 633 miles.  That is our DX record so far.  Not bad for 92 milliwatts to a dipole on 40 meters. 

Most of my contacts come as a result of pleas for assistance on DX Summit or the SKCC Sked page.   But I did make one "random" contact: Contact #6 with N2VGA.  He just heard my CQ and gave me a call.  FB. 

I checked to see if OM Glen Yingling W2UW -- the guy who started all this with his ET-1 -- is still around.  He became a silent key in 2012.  But his ideas live on... 

SPRAT 137 (Winter 2008/09) has a great article by QRP hero G3XBM.  Roger built a version of the ET-1.  His was for 80 meters and he called it the FETer.   FB.   I was struck by his estimate of the sensitivity of the ET-1 receiver: -100 dbm.   I measured the N0WVA receiver (the one that I am using) has having a minimum discernible signal of -93 dbm.  Pretty close.  We may be at the limit of what you can expect from a single transistor receiver. 

SPRAT 137 had something else that really resonated with me.  G3YVF had an article on a minimalist rig using only one 6V6 tube.  Geoff opened the article with this warning "Don't try this unless you have a set of balanced armature type DLR 'phones as they are really sensitive."  I have a collection of old headphones that I picked up at hamfests in London years ago.  When building the ET-2, I checked all the old phones for sensitivity.  A set marked DLR was the most sensitive.  So Geoff's observation had been independently confirmed.   QRP Quarterly had an article comparing the sensitivities of old headphones -- we should dig that article up.   

SPRAT #137 is a reminder of what a great resource SPRAT -- The Journal of the GQRP Club -- really is.  As we say on SolderSmoke, if you are not a SPRAT subscriber you are just wrong!  Here is how to join GQRP and subscribe to SPRAT: http://www.gqrp.com/join.htm

Saturday, September 22, 2018

Pete's New Sudden Transceiver


Check it out!  Note the Juli-yellow front panel color.   Featuring FT-8 and WSPR capability.  Go Pete! 

http://n6qw.blogspot.com/2018/09/2018-year-of-ssb-transceivers_14.html

Sunday, September 2, 2018

SolderSmoke Podcast #206 -- GQRP CONVENTION SPECIAL EDITION


SolderSmoke Podcast #206 is now available: 

http://soldersmoke.com/soldersmoke206.mp3

-- SolderSmoke resumes after a busy summer.

-- We did a portion of #206 via Skype at the GQRP Convention.  Thanks to Steve G0FUW for setting this up.  A portion of our participation appears at the end of the podcast. 

-- Pete's SDR Rig and his new involvement with WSPR and FT-8

-- The allure of SDR and the pitfalls of complexity. 

-- Bill's 135 foot Doublet, 75 AM, 60 USB and 30 Meter CW. 

-- Plans to change the IF of Bill's HRO dial receiver. 

-- Thinking (again) about sold stateing the HW-101. 

--  Hans Summers, QCX and QSX rigs.  

MAILBAG: 

Ralph builds Pete's LBS receiver.  FB!  

Saturday, May 5, 2018

SolderSmoke Podcast #204 April 1, SPRAT Cover 2, uBITX mania, MAILBAG


SolderSmoke Podcast #204 is available! 

http://soldersmoke.com/soldersmoke204.mp3

5 May 2018

April 1 Recap -- We thank you for your support! 

Pete's Rig on Cover of SPRAT 174 

uBITX Mania

uBITX Dual Conversion Design

uBITX Gettng more out of the Arduino/Si5351 combo

uBITX KD8CEC's amazing software

uBITX Future Possibilities

uBITX On-the-Air Experiences, with CW too! 

MAILBAG

KD8CGH's Hyderabox -- THERE ARE TWO! 
QSO with N1AW's cardboard uBITX
DuWayne on QSO TODAY
Jack 5R8SV -- Radio Gods NOT Happy
Jack Purdum W8TEE -- Thanks OM
Charles AI4OT
Chris KB4PBT 15 inch telescope
John WJ0NF Reading SolderSmoke
Ken W8KTP Ordering a uBITX 
Darren KG7KOI  Listening
Gary AK4NA  New Word:  "Cabinetize" FB OM! 


Sunday, April 29, 2018

"The Thrill That'll Hit Ya..." AGAIN! Three cheers for Pete, SPRAT, and GQRP


On the cover of issue 173 of our beloved SPRAT magazine they had my little Direct Conversion receiver.  We joked on the podcast about the old song by Doctor Hook about getting on the "Cover of the Rolling Stone."  Well, on the cover of issue 174 they have one of Pete's magnificent creations.  

Thanks again to the guys who put so much work into SPRAT magazine.  They are now looking for some help.  Please subscribe, and check out page 4 of issue 174 for details on the help that GQRP is looking for.  


Wednesday, February 7, 2018

Understanding Switching Mixers (as in the Ceramic DC RX)

W3JDR's Comment on my post about the DC RX mixer got me thinking.   He was right -- my explanation of the mixer action wasn't quite complete, especially as far as switching mixers are concerned.  I remembered that I had written about this in the SolderSmoke book.  Below you can see the part of the book in which I discuss switching mixers.  Realize that the two diodes in F5LVG's mixer play the same role as the two gates in Leon's circuit.  It will be worth your while to sit down with Leon's circuit diagram, his frequency chart,  and a ruler and really go through this so you can SEE and really understand how the two gates (or switching diodes) generate sum and difference frequencies.  

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

I guess I still yearned for clarity and intuitive understanding...  Time and time again, as I dug into old textbooks and ARRL Handbooks and promising web sites served up by Google, I was disappointed. 
Then I found it.
It was in the Summer 1999 issue of SPRAT, the quarterly journal of the G-QRP Club.  Leon Williams, VK2DOB, of Australia had written an article entitled “CMOS Mixer Experiments.”  In it he wrote, “Generally, mixer theory is explained with the use of complicated maths, but with switching type mixers it can be very intuitive to study them with simple waveform diagrams.” 
Eureka!  Finally I had found someone else who was dissatisfied with trigonometry, someone else who yearned for the clarity of diagrams.  Leon’s article had waveform diagrams that showed, clearly, BOTH sum and difference output frequencies.



Switching mixers apply the same principles used in other kinds of mixers. As the name implies, they switch the mixing device on and off.  This is non-linearity in the extreme.
Not all mixers operate this way.  In non-switching mixers the device is not switched on and off, instead one of the signals varies the amount of gain or attenuation that the other signal will face. And (as we will see) it does this in a non-linear way.  But the basic principles are the same in both switching and non-switching mixers, and as Leon points out, the switching circuits provide an opportunity for an intuitive understanding of how mixers work. 

Let’s take a look at Leon’s circuit.  On the left we have a signal coming in from the antenna.  It goes through a transformer and is then applied to two gate devices.  Pins 5 and 13 of these gates determine whether the signals at pins 4 and 1 will be passed on to pins 3 and 2 respectively. Whenever there is a positive signal on gate 5 or on gate 13, signals on those gaps can pass through the device.  If there is no positive signal on these gates, no signals pass.  Don’t worry about pins 6-12.




RF A is the signal going to pin 4, RF B is the “flip side” of the same signal going to pin 1.  VFO A is a square wave Variable Frequency Oscillator signal at Pin 5. It is going from zero to some positive voltage.  VFO B is the flip side.  It too goes from zero to some positive voltage. 
Look at the schematic.  Imagine pins 5 and 13 descending to bridge the gaps whenever they are given a positive voltage.  That square wave signal from the VFO is going to chop up that signal coming in from the antenna.  It is the result of this chopping that gives us the sum and difference frequencies.  Take a ruler, place it vertically across the waveforms, and follow the progress of the VFO and RF signals as they mix in the gates.  You will see that whenever pin 5 is positive, the RF signal that is on pin 4 at that moment will be passed to the output.  The same process takes place on the lower gate.  The results show up on the bottom “AUDIO OUTPUT” curve. 
Now, count up the number of cycles in the RF, and the number of cycles in the VFO.  Take a look at the output. You will find that that long lazy curve traces the overall rise and fall of the output signal.  You will notice that its frequency equals RF frequency minus VFO frequency.  Count up the number of peaks in the choppy wave form contained within that lazy curve.  You will find that that equals RF frequency plus VFO frequency. 

Thanks Leon!  

Sunday, December 31, 2017

Ceramic DC Receiver on the Cover of SPRAT. Happy New Year to All! Straight Key Night.


G-QRP very kindly put my little DC Receiver on the cover of issue Nr. 173.   (Very sorry to see that GM3OXX has become a Silent Key. ) 

As we often say on the podcast, if you are not subscribing to this wonderful magazine, you are missing out on a lot of great ideas and circuits. Information on how to join the club and start receiving SPRAT can be found here: http://www.gqrp.com/join.htm   It is only 22 bucks! 

Reminder:  Straight Key Night is upon us.   It begins at midnight UTC 1 January.  It is a great way to begin the new year.  My HT-37 and my Drake 2-B are warming up now (and are helping to keep the shack warm on a very frigid day).   HNY to all!   73    Bill 





Tuesday, October 10, 2017

SPRAT -- The 007 Connection


The eagle eye of Brent KD0GLS spotted this frame in the 007 movie "Casino Royale."  
Wow -- I just knew those GQRP guys had to be much cooler than they seemed.  I guess there were some indications: They do seem to talk quite a bit about "Q".  There is that weird fondness for Parasets. I understand that several of the senior GQRPers drive Aston Martins.  And that Dobbs guy -- a kindly retired Anglican minister you say?  Really?  I can just hear him saying it:  "Dobbs, George Dobbs."  
Designer: Douglas Bowman | Dimodifikasi oleh Abdul Munir Original Posting Rounders 3 Column