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Showing posts with label homebrew hero. Show all posts
Showing posts with label homebrew hero. Show all posts

Sunday, May 28, 2023

Jerry KI4IO (Wizard of Warrenton) Describes His ALL ANALOG Phasing Transceiver -- Bob Crane FDIM interview #3 (audio)

Wow, this one really resonated with me.  Jerry had me won over when, early in the interview, he described his decision to dispense with the Si5351/Arduino combo:  "I said the hell with this digital stuff!"  I hear you Jerry.  I feel your pain OM.  

Jerry then goes on to describe a rig with bits of circuitry from some legendary sources:  The Ugly Weekender transmitter.  SSDRA and EMRFD.  W7ZOI's 1968 Direct Conversion receiver.  

Jerry discusses the "presence" of the direct conversion receiver.  And he decries the pernicious effects of AGC.  (Indeed, real hams MANUALLY control the gain.) 

The Wizard of Warrenton then shares some important tribal wisdom:  After building that new piece of gear, leave it on the bench for a couple of weeks.  Beware of "radio infatuation" (what a great term -- we will have to include this in the lexicon).    Jerry points out that while at first, the new rig will seem just perfect, with time time the need for improvements and modifications will become apparent. 

Jerry also has connections to India and Nepal (where he helped Father Moran).  See: https://www.qrz.com/db/KI4IO

Here is W8SX's interview with Jerry: 

http://soldersmoke.com/KI4IO23.mp3

Thanks Jerry!  Thanks Bob! 

Saturday, May 27, 2023

Hans Summers G0UPL and his new QMX: The Bob Crane W8SX FDIM Interviews Part 1 (audio)

http://qrp-labs.com/qmx.html

We are very pleased and grateful to present this year's series of Four Days in May interviews by our FDIM correspondent Bob Crane W8SX.   Once again Bob did an outstanding job interviewing the FDIM participants. 

In this interview, the amazing Hans Summers talks about his latest QRP Labs kit, the QMX.  It is a combination of the QCX Mini and the QDX.  

Hans explains the M:  QMX. The M is for Marriage. Magnificent. Merger. Marvelous, many things like that. It’s what you get when you marry the mechanical and conceptual design of QCX-mini, with the SDR, multi-band digital implementation of QDX. Simply: QDX + QCX-mini = QMX. 

It has a very clever switching power supply that automatically adjust to prevent spurs and harmonics from the power supply from appearing in the band of interest. 

I was especially interested in his plans to implement an SSB option in future software updates.  Hans will use the same very complicated SSB generation scheme used in the trueSDX rig, but hopes to achieve higher performance and  improved signal quality due to the much more robust hardware of the QMX. 

Here is the interview: 

http://soldersmoke.com/G0UPL23.mp3

Here is the QRP Labs site about the QMX:  http://qrp-labs.com/qmx.html

Here is the QRP Labs web site: http://qrp-labs.com/

And here is a really wonderful and very current article by Hans on the evolution of QRP Labs and its rigs from 2010 right on up through 2023 and the QMX.  It is really interesting: 

http://qrp-labs.com/images/qmx/docs/fdim2023.pdf

Thanks to Bob Crane W8SX, Hans Summers G0UPL, and all of the FDIM organizers. 

Hans G0UPL-- Homebrew Hero

Wednesday, May 24, 2023

Farhan Speaks to Students about Satellites and Direct Conversion Homebrew Receivers (audio)


In our talks at the local high school we have frequently mentioned Ashhar Farhan, his Cubesat experience, and his use of a direct conversion receivers teach electronics to students in Hyderabad, India.  So we were really please to have the opportunity to bring Farhan himself in to speak to the students we have been working with.  

Here is the audio of Farhan's talk: 

http://soldersmoke.com/FarhanTJ.mp3

The acoustics in the room are not great, so you may have to listen carefully, but it is worth it.  Farhan dispenses a lot of tribal knowledge and wisdom about satellites and about the value of homebrewing simple radio equipment. 

Saturday, March 18, 2023

Needed: More Info on the Cuban Islander or Jaguey DSB Transceivers

CO6CBF: "I began operating on the HF bands using homebrewed radios. Mainly on CW running just 10 Watts. My very first phone transmitter was a controlled carrier AM modulator for the 160m band using tubes and components salvaged from an old TV set."

My good friend Dean KK4DAS has built a DSB rig for 10 meters and is working a lot of DX with it.  Peter Marks in Australia has also jumped into the DSB game.  A few of the students we are working with at the local high school may get their General Class licenses and convert their Direct Conversion receivers to Double Sideband transceivers. 

All of this has caused me to reminisce about the famous Cuban Double Sideband rigs. Homebrew Hero Arnie Coro CO2KK used to talk about these rigs on his "DXers Unlimited" program on Radio Havana Cuba.   But Arnie recently passed away, and with him I think a lot of the background info on the Cuban DSB rigs has also disappeared. I find very little about these rigs on the internet -- I have not been able find a single picture.  The Radio Havana Cuba archive of Arnie's shows has disappeared.  

Back in February I talked to Yulian CO6YI on 20 meters about the Cuban DSB rigs.  He said he had a lot of background info on them, and said he would try to send it to me.  I hope he is able to do this. 

The results of my initial Googling appear below.  There has to be more out there. I'm thinking that there must be a lot of background info on the Islander and Jaguey rigs sitting on the hard drives of radio amateurs.   It is time to give this info wider circulation.  Please send me any info you have on these rigs.  Of particular interest would be schematic diagrams and photos of the rigs.  

 

https://www.paara.org/newsletter/2000/graph200007.pdf



Date: Mon, 22 Mar 2004 17:48:59 -0500
From: "Prof. Arnaldo Coro Antich" 

Subject: Re: GB> 6EH7 vs. 6EJ7 as RF Amplifier

 Dear amigo Chris:
You are absolutely right !
EF184 is the best pentode for RF amplifier duty...
But, let me ask you something... have you thought
about the ECC88 and the even better ECC189 dual
triodes that were designed for TV tuner work, and
that incidentally were also about the last vacuum tubes
ever designed from ""scratch"" until Phillips and other
European manufacturers stopped from making
receiving type vacuum tubes.
The ECC189 is simply wonderful for a front end !!!
I am sure that you are aware of our limitations here at
my QTH regarding the possibility of obtaining solid
state modern devices... so we still make ""new"" ham radio rigs using mostly
vacuum tubes...
We even still make a version of "" The Islander"" a DSB transceiver with
direct conversion vacuum tube receiver...
Tube lineup is
EF184 RF amp
ECH81 product detector
ECH81 triode section not used
ECL82 triode audio preamp
ECL82 pentode audio output
6AH6  VFO ( Russian equivalent 6*5P )
Audio filter provided by good working brain of
operator !!!
Keep up the good work amigo !!!
73 and DX
YOur friend in Havana
Arnie Coro
CO2KK

http://ibiblio.org/modena/GLOWBUGSpiobaire/glowbugs.piobaire.weekly.html

Today’s first question came from a long time listener in India. Rajiv 
tells me that at this moment he is not able to pick up our station on 
the shortwave bands, and he rightly assumes that this is because of the 
very low solar activity… but Rajiv who lives in the garden city of 
India, Bangalore, the home of the nation’s electronic and other high 
tech industries, is able to read the scripts of the program that are 
made available to several short wave listeners clubs e-mail distribution 
lists. Rajiv tells me that he wants to obtain the electronic files of 
the Super Islander amateur radio transceiver to compare the circuit 
diagrams and design philosophy with a similar project that is becoming 
very popular among Indian radio amateurs.
Ok amigo Rajiv… I have already sent you all the files including some 
nice digital photos of the first prototype of the Super Islander, that 
as you will see, has two final amplifier options , one built using NPN 
RF power transistors, and the other one using two vacuum tubes that are 
very easy to find here in Cuba from recycled TV sets. The Super Islander 
is a single band transceiver that can be built for the 160, 80 or 40 
meter bands. Here in Cuba amigo Rajiv, the most popular amateur band 
nowadays is two meters, using the FM narrowband mode, and the second 
most popular band among Cuban radio amateurs is 40 meters, that’s why 
most of the Super Islanders are built for operating between 7.000 and 
7.150 kiloHertz.  The double sideband signal generated by the Super 
Islander simple circuit is very stable, and very few if any radio 
amateurs that contact stations using the Super Islander are able to 
detect that it is a double side band and not a single side band signal 
what they are hearing. One of the most outstanding features of the Super 
Islander single band amateur radio transceiver is that it is modular, so 
those who want to build it, are able to build and test each module as a 
single project, and after all the modules are fully tested, then they 
are easily wired together . The parts count, that is the number of 
components required to build a Super Islander was kept intentionally as 
low as possible, both to simplify its construction and to increase the 
reliability. I hope that amigo Rajiv in Bangolore , India will be able 
to make good use of the Super Islander’s files, and maybe even go ahead 
and build one , as the parts required are almost universally available, 
because that was one of the design requirements that I set when starting 
the  Super Islander project more than fifteen years ago….You can learn 
more about this simple amateur band transceiver by sending a request for 
the Super Islander files to arnie@xxxxxx … I will send it as a dot zip 
file and you will be able to see circuit diagrams, photos and full 
descriptions of the different modules of this nice little rig, that has 
proven itself under the most difficult circumstances, like handling 
emergency communications links during tropical storms.
http://www.hard-core-dx.com/hard-core-dx/2007/msg02587.html


Beginners generally build one of two radios; the vacuum tube Islander or the solid state Jaguey. The Islander is a DSB/CW Cuban design using a very clever low parts count circuit and a direct conversion receiver. The Jaguey, named for the Jaguey Grande Radio Club in Matanzas province, is a generic design, with a DC receiver, DSB and CW, using solid-state components. Many of its ideas are from Wes Hayward's W7ZOI's Solid State Design for the Radio Amateur. The lack of mechanical filters or quartz crystals to homebrew SSB filters made Cuban designers CO5GV, CO2JA and CO2KK choose a DSB and CW rig. Fitted with good quality capacitors for the VFO, it works quite well from a 12-volt car battery in hurricane emergencies.

Monday, December 26, 2022

A Blast from the Past: TR on Homebrewing (sort of)

 Theodore Roosevelt

"It is not the critic who counts; not the ham who points out how the homebrewer stumbles, or where the builder of rigs could have built them better. The credit belongs to the ham who is actually at the workbench, whose hands are scarred by solder and metal and glue; who strives valiantly; who errs, whose amp oscillates again and again, because there is no effort without error and shortcoming; but who does actually strive to build his rigs; who knows great enthusiasms, the great devotions; who spends himself in a worthy cause; who at the best knows in the end the triumph of homebrew  achievement, and who at the worst, if he fails, at least fails while daring greatly, so that his place shall never be with those cold and timid operators who neither know victory nor defeat.”


Saturday, May 14, 2022

Mr. Carlson's Grand Receiver Restoration Project -- Your Input Sought (video)


Mr. Carlson (VE7ZWZ) is launching a series of videos on the restoration of some old boatanchor receivers.  I have been working on an old HQ-100, so this all resonates well with me. 

He asked for viewer input on which of these receivers he should work on first.  I voted for the SP-600 because I wanted to see how difficult it really is to change out the infamous Black Beauty capacitors.  My second choice was the R-390, but I warned Mr. Carlson that he might need a chassis crane for that one.  No kidding.  Really.   

I look forward to watching the series.  Thanks in advance Mr. Carlson. 

Saturday, May 7, 2022

SolderSmoke Podcast #237 is available: TV Show! No! W9YEI's 1939 TV. 1712 Rig. HQ-100. New SDR Rig and Book. JF3HZB's VFO Digital Dial. FIELD DAY! PSSST. MAILBAG


SolderSmoke podcast #237 is available:  http://soldersmoke.com/soldersmoke237.mp3


Travelogue -- New York City!  Stickers!
And about that trip to Los Angeles for the SolderSmoke Cable TV show... 

Well, it fit in well with SolderSmoke's UNFORGETTABLE appearance on the Oprah book club.
And TechieTatts? Daughter worried about listeners rushing to get tattoos -- A risk we were willing to take.

https://in.pinterest.com/padmakumar10/techie-tatts/

This episode is sponsored by PartsCandy.  GREAT test leads: https://www.ebay.com/usr/partscandy

Bill's Bench

Tracking down Johnny Anderson's 1939 or 1940 homebrew TV receiver.

https://soldersmoke.blogspot.com/search?q=Anderson
Working with Joh DL6ID.
Jean Shepherd's January 1973 description.
FlickLives web site and Steve Glazer W2SG have lots of info on Shep and his friends.
Internet allows us to look at TV articles that were being published.
We've concluded: Probably 1939 or 1940, using an RCA 913 1 inch CRT tube. 

Lots of ideas from IRE Journal, QST, and Gernsback magazines.
Quite an achievement! Amazing how much pre-war TV progress there was.  

17-12 rig
All boxed up and working DX!
Figured out how to display both 17 and 12 on the same LED. https://www.youtube.com/watch?v=kAmmFZyFu8w
Drain protector for speaker cover. Copper tape to cover horrible cabinet making.
I think I need a Hex Beam.

Hammarlund HQ-100
Needed some maintenance.
I started to look more closely at it.
Got the Q-Multiplier to work -- it really adds a lot on CW.
Makes me feel guilty about all the QF-1s...
Using the 100kc calibrator with a 455 kc crystal as a BFO,
keeping Q multiplier below oscillation point.
Moved the BFO switch to the front panel. Helps a lot.
Need to fix the S-meter AVC circuitry.
Much more sturdy than the S-38E.
S-38E 1957-61 $54.95 5 tubes.  AC/DC.
HQ-100 1956-60 $169  10 or 11 tubes.  Power supply,  regulator.
You get what you pay for.  

Pete's Bench

Jack Purdum and Al Peter's new SDR rig and book (featured on the SS blog Amazon ad).
JF3HZB's beautiful digi VFO.
Backpack antenna for Field Day?  
Pipsqueak Disaster -- Too simple?
Peashooter Eye Candy.
Build Something Different.

MAILBAG

James W0JKG CBLA -- Others are building MMM too!
SM4WWG // Jörgen  Wonderful message.  Joined GQRP.  No longer "wrong."
Dennis WC8C Libraries for Max2870 board.
Jack NG2E  Progress on the Right to Repair movement. 
Jim K9JM  Someone cutting into our business with Solder candles!  
Chuck  WB9KZY Correctly identified the location of the IBEW sticker.  As did Dan Random.
Dave Bamford (who lives nearby) suitably impressed. 
Farhan wrote to us about a video on Don Lancaster.  Homebrew keyboards!  Yea!
Dean KK4DAS  QRP to the Field.  HB2HB 40 SSB   QRP  I feel virtuous.  
Todd K7TFC likes my ingenious use of the drain screen as the speaker protector on the 17-12 rig. 
Todd  had good thoughts on granular approach to homebrewing as seen in the Don Lancaster video.
Lex PH2LB HORRIFIED by my reverse polarity protection circuit.  This is a touchy subject! (as is WD-40!)
Rogier PA1ZZ sending great info on SWL and numbers stations.
Jesse N5JHH -- The guy who made the IBEW stickers -- Liked the NYC stickers. 
Steve N8NM has a new antenna article on his blog: https://n8nmsteve.blogspot.com/
Randy AB9GO Agrees -- Can't GIVE old 'scopes away. 
Dino SV1IRG Liked the 17-12 rig videos. 
Steve Hartley G0FUW Murphy's Law of Enclosures. 
Ralph AB1OP FB on the 17-12 Rig. 
Roberto XE1GXG --Our correspondent in Guadalajara. Petulant, irritable people on the computer scene.

Have some gear looking for a good home:   Tek 465 'scope from Jim AL7R W8NSA.   SBE Transceivers.  Windsor Signal Generator.  Let me know if you are interested and can either pick up or arrange shipping.  



John Anderson W9YEI Homebrew Hero

Thursday, September 23, 2021

Great News for Homebrewers: JF1OZL's Amazing Web Site is Back!


I was very happy to read this morning (on the G-QRP e-mail list) that the amazingly useful web site of Homebrew Hero Kazuhiro Sunamora has been resurrected after too many years in 404 status. 

Here it is:

https://www.qrp-ja.net/jf1ozl/index.html 

There is a LOT of tribal knowledge and lot of great ideas on his site.  Kazuhiro-san has apparently quit wireless, but is climbing mountains near his home.  We hope is doing well and that he will someday return to radio (perhaps for the peak of cycle 25).  

We last posted about him back in 2011.  In the comments to that post you can see the sad news about the demise of his web site (which is now back on the web): 

http://soldersmoke.blogspot.com/2011/12/homebrew-hero-kazuhiro-sunamura-jf1ozl.html

JF1OZL's bio: 

My name is Kazuhiro Sunamura. I am a 50 year old mechanical engineer, born in 1956. I am not an engineer in electronics. I have been interested in electricity and radio from the age of ten. For the last ten years, I have been active on my ham radio station JF10ZL. I have also written articles about my some of my radio projects in Japanese for the Japanese CQ Magazine. Now I have decided to get onto the internet and will take the opportunity of showing you my equipment and ideas. Please have a look at my schematics. I will be very happy if this material helps you with your own radio projects. I am a member of the J.A.R.L. affiliated Tsuchiura Club, the local ham club in my home town.


Sunday, August 15, 2021

Sam KD2ENL's Homebrew Integrated Circuit Chips


Sam Zeloof KD2ENL does some really inspirational work on the homebrewing of IC chips. We first posted about this back in 2018, when Sam was 17: 

Sam has some very impressive gear  -- I found myself wondering if that could really be a home lab. But it is.  It is apparently in his garage in New Jersey.  Hack-A-Day reports that Sam got a lot of the gear on e-bay.  And they note that living near Princeton University (great dumpsters!) also helped.  Here is some background on Sam's workshop: 
and

Sam and his brother Adam KD2MRG are students at Carnegie Mellon University in Pittsburgh. 

Thanks to Hack-A-Day for alerting us to this: 

Wednesday, May 27, 2020

Emilio's Mirror of JF1OZL's Site

JF1OZL's site was for many years a real treasure trove and source of inspiration for homebrewers around the world.  It recently disappeared from the internet.  And I find no listing for JF1OZL on QRZ.com.   I hope Kazuhiro is OK.  

Emilio in Mexico has put up a mirror site.  Thanks Emilio.  We need to protect and preserve JF1OZL's work. 

https://www.emilio.com.mx/jf10zl/

Here is a SolderSmoke blog post on Kazuhiro from 2011: 

https://soldersmoke.blogspot.com/2011/12/homebrew-hero-kazuhiro-sunamura-jf1ozl.html

Thursday, February 27, 2020

From a Student of C.F. Rockey, W9SCH

C.F. Rockey W9SCH

We have discussed the monumental work of C.F. Rockey, W9SCH, SK before.  Yesterday a comment appeared under that post that is just too good to leave buried in the comments.  It appears below.   Jeff's comment also caused me to dig up my small collection of "The Five-Watter" issues from the Michigan QRP Club.  Rockey wrote a column for that magazine.  It contains a lot of tribal knowledge.  Here is Jeff's look back:  


This turned up for me in a Google search for "Charles Rockey QRP ARRL" during a phone call with a friend of mine who was bemoaning that he never got a novice license because he could not master Morse code (he is in his mid-60s, as am I). I was taken back to the communications electronics class I had my freshman year at New Trier East in Winnetka (not Wilmette) IL in 1971. That class was taught by none other than C.F. Rockey, known to us students as The Rock. I think about him fairly often because I grew up to become a very hands-on engineer and can recall parts of his class quite clearly, even at this remove. Somewhere I still have the reports we had to write (typed on a typewriter) each week. He was a huge influence on me and I was saddened to have his passing undeniably confirmed for me. I have the little chemistry book he authored beside me now *Electrons, Atoms and The World* and am glad to be able to read his obit. One thing needs to be added to it: He won the ARRL 5000 mile-per-watt award for working Anzio, Italy from his home north of Chicago on 5W. I am very lucky to have had him as a teacher and mentor for those years. Thanks for sharing. Cheers, Jeff Mizener, DFW-TX

Monday, January 21, 2019

A Homebrew HRO Dial by DL6WD, Homebrew Hero


Take a look at that beautiful rig in the bottom of the cover pictures. (A closer shot appears below.)  That is an HRO dial, right?  Or is it?  

No, it is not.  In the picture we see the homebrew receiver designed and built during the 1960s by Rudolf Fishcer, DL6WD.  It is magnificent in every respect.  Because I have been working with the HRO dial and gearbox given to me by Armand WA1UQO, the tuning dial on this receiver caught my attention. 

Here is what DL6WD says about this part of his project:  "The main tuning gear was built around a BC-221 tuning capacitor and reduction gear. The counter dial and tuning knob are the result of four weeks of labor, The counter dial reads in tens of kHz, where the main tuning knob has a calibration of 200 Hz per division, from an HRO inspiration."  The counter is in the little window to the upper left of the tuning knob. The window to the upper right is a phase-lock indicator. (See below.)

By the way, by the time DL6WD got finished with this all solid state receiver it weighed in at 52 pounds.  Rudolf noted that "excessive shielding pays in electrical performance, but not in weight!" 

DL6WD earns the title "Homebrew Hero."




Monday, July 30, 2018

Wow. Mr. Carlson's New Old-Time Radio and Test Gear Lab. VE7ZWZ -- Homebrew Hero



It has been a while since we last visited Mr. Carlson's lab.  As always, we found it amazing.  The awesomeness just keeps increasing. Previous visits: https://soldersmoke.blogspot.com/search?q=Carlson

As was the case before, this is really almost too much.  THREE DX-100s in the shelves.  A massive collection of tubes, some sorted, some un-sorted.  But don't worry -- Paul has a good memory and remembers where everything is.  I believe him. 

For his amazing shack and workshop(s) and for his willingness to repair old-time test gear, Paul VE7ZWZ clearly deserves homebrew hero status.  

Thanks Paul. 

Friday, July 20, 2018

A Rig with Maximum Soul: The 5 Band Transceiver of Glenn KU4NO

That's the front panel.  Glenn's kids and grand kids liked sitting on his lap while he played radio and putting stickers on it

This is one of the best HB2HB contacts I've had.   I was just getting ready to sign off on 40 meters when I heard someone calling me. It was KU4NO.  I thought I'd just give the OM a quick report.  Then he said, "My rig is homebrew too."   And wow, it is indeed!  When he said this my first thought was that maybe this was a kit rig, but no, it turns out that this rig is the scratchyist of scratch-built rigs -- true hardcore hardrock homebrew. 

I checked my log.  I had worked Glenn once before, in December 2001.  I was in the Azores.  And he was using this same rig.  Glenn told me that for all these years, this has been his ONLY rig.  A friend gave him a modern commercial rig, but he prefers this one.  I understand completely.  

At first, Glenn made me promise not to share the pictures with anyone. He seemed a bit embarrassed by his creation.  I told him that SolderSmoke readers would appreciate his rig and see the value of it. I explained that we all have soldering iron scars on our fingers, and clothing that has been stained by ferric chloride.  We LIKE ugly.  It took some persuasion, but I got  him to agree to let me share this with the group.  

Glenn reports it is based on a "5 band transceiver" circuit in the 1976 or 1977 handbook. (i don't have one and can't find it on-line -- can anyone get us a copy of the schematic and article?)

So I say THREE CHEERS for Glenn KU4NO and his homebrew 5 band transceiver.   For me, the stickers are the most important feature of this rig.  Please e-mail me your comments on Glenn's rig - in an effort to let him know how much we appreciate and understand his effort, I will pass them on to him. I wish more hams would follow his example. 

Glenn wrote: 

Oh well I'm not too concerned about who sees it. 
I just wouldn't want to cause anyone to follow my example. 
Maybe you could call it "a tornado goes through a junkyard."
Just kidding around ...no restrictions...I'm sure it will be forgotten soon ..... but I will be innocent of any harm caused by it. 
Its the only rig I've ever owned when we contacted before it was with it. 

The inspiration article in the 76 or 77 handbook is worth a look.  
The VFO tuning cap and mount came from a CB "slider" one of my brother-in-laws gave me  it seems to work well
 
Glenn


Picture Above:  top view upper left power out two IRF 510s from w2eby ( I think) 30+ to 60+ watts across HF love this circuit, small board connected at right angle is 1/2 watt driver from Harrys Homebrew page 2n2222 driving 4 2n2222s beautiful circuit
lower left power transformer 
one of two wafer band switches in middle   ....  under wafer switch is hf mixer and single balanced mixer to generate ssb
 LO from progressive receiver top right ... heat sink just to left and lower unused voltage regulator
  RF amp and wafer switch lower right used for transmit and receive
 

LO tuning cap and hf mixer modulator circuit
 

 RF amp

 Crystals for mixing, BFO, old detector circuit.  Old circuit that repeated CQ call, chip from Radio Shack

Some micro relays ...... audio amp at bottom and two switchable compressor circuits one using an SL 1626 and one lifted from a President model CB radio  and some filter caps
 

New IF AGC audio detector uses three ca 3028As from 67 handbook schematic is wrong can you find the mistakes? it was printed wrong twice i use an s meter with it


Close up of power output and lower left  rf output filters  
 


Friday, June 1, 2018

INTERVIEW: Bob Crane Talks to Jack Purdum W8TEE at FDIM. Definition of "Homebrew."


Jack Purdum has been making enormous contributions to the radio art.  His background with digital technology has opened many doors for homebrewers, especially through his books on the use of the Arduino microcontroller.   I think his new "JackAl board" is really going to shake things up.  I was glad that our correspondent in Ohio, Bob Crane W8SX, caught up with Jack and interviewed him for soldersmoke: 


But I have one small disagreement with Jack.   It has to do with the definition of "homebrew."   Jack seems to define true homebrew as "designing and building your own rig from scratch."  My problem is with the "designing" part.  By this definition, those intrepid heroes of days-gone- by who saw a schematic in QST, ripped apart some old broadcast radios, and used the parts to build a 50 watt CW transmitter with a regen receiver were not true homebrewers.   I would maintain that they were.  I agree with Jack that kit building is a bit different, and of course designing the rig yourself earns you the coveted "designer" designation.  But for me, if you start with a schematic and an article, gather the parts and build the thing yourself, that is a homebrew project and you are a homebrewer.  After all, even the designers are very often making use of standard blocks of circuitry (Colpitts oscillators,  common emitter amplifiers, power supply circuits, etc.)

I think we will have to turn to our lexicon expert Steve Silverman for a ruling.  

In any case, thanks to Bob Crane and to Jack Purdum. 




Wednesday, May 16, 2018

Youngest Homebrew Hero: 17 year-old Sam Zeelof Makes His Own Integrated Circuits


Seventeen year-old Sam Zeelof, KD2ENL, is making his own integrated circuits in his garage. 

Wow.  This makes me think about another seventeen year-old -- the fellow who appears on pages 63-64 of Cliff DeSoto's "200 Meters and Down." (I have the story on page 81 of "SolderSmoke -- Global Adventures in Wireless Electronics.")   In the early days of radio that kid amazed us by making his own vacuum tubes.  Sam Zeelof is clearly following in that tradition. 

No "mysterious black boxes" for Sam!  No "appliance chips" for him!  FB OM.  

This is really amazing.  Here are the links: 

https://spectrum.ieee.org/semiconductors/devices/the-high-school-student-whos-building-his-own-integrated-circuits


One of Sam's chips
Thanks to Bruce KC1FSZ for alerting us to this amazing work. 
Designer: Douglas Bowman | Dimodifikasi oleh Abdul Munir Original Posting Rounders 3 Column