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Author Topic: "A Three-Transistor Receiver for the Beginner" ARRL 1968 -- Build  (Read 107150 times)

G3EDM

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RE: "A Three-Transistor Receiver for the Beginner" ARRL 1968 -- Build
« Reply #30 on: June 19, 2013, 05:04:53 AM »

I've found that clear nail varnish is very good.

Peter, you know that strange feeling when you think you've had the same conversation before, sometime in the past? I remember someone saying exactly the same thing some time last year (perhaps you!) with the additional quip: "Plus, it reminds you of your mother."

73 de Martin, KB1WSY
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G3EDM

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RE: "A Three-Transistor Receiver for the Beginner" ARRL 1968 -- Build
« Reply #31 on: June 26, 2013, 06:01:26 AM »

Time for Chapter Eight. I was very surprised how good the performance of this little receiver was. But there was a big problem: this was limited to the 40m band. On 80m all I got was heavily overloaded CW and SSB with no detection. On 20m the regeneration was uncontrollable "motorboarding." And so on. With a lot of help from this forum,these problems on 80 and 20 were solved by:

--Building new coils with looser coupling (fewer turns on the primary, and a much bigger space between primary and secondary).
--Drastically altering the value of C9, the detector source capacitor.
--Varying the antenna coupling by adjusting the (ceramic) antenna trimmer with a screwdriver.
--It was also suggested that I should add an RF stage in front of the detector (not done yet).

So I decided to do a major upgrade of my receiver, to incorporate what I had learned and replace the experimental rat's nest of improvised alterations with permanent ones. But I faced the dilemma that it would "ruin" my "authentic" museum-piece ARRL receiver. I found a "non-destructive" solution ... and the receiver is now a good performer on four bands (160, 80, 40, 20) without losing any of its "basic" charm. The remaining two bands (15 and 10) are still dead but that's not a major concern right now.

http://tinyurl.com/q5vcls5

73 de Martin
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G3EDM

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RE: "A Three-Transistor Receiver for the Beginner" ARRL 1968 -- Build
« Reply #32 on: June 26, 2013, 07:11:08 AM »

Drat, I did paste in the link to the new photo gallery but I forgot to bring it to people's attention. Let's try again: Chapter Eight of the receiver build can be found here:

http://tinyurl.com/q5vcls5

73 de Martin, KB1WSY

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KQ6EA

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RE: "A Three-Transistor Receiver for the Beginner" ARRL 1968 -- Build
« Reply #33 on: June 26, 2013, 08:17:11 AM »

Amazing work, Martin!

73, Jim
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W6MZ

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RE: "A Three-Transistor Receiver for the Beginner" ARRL 1968 -- Build
« Reply #34 on: January 25, 2014, 09:15:32 PM »

I made my first QSO as WN6GZS in October or November 1970 using this receiver, with W6MJO and WN6ICQ about a mile away. 

Many of the parts were scrounged from WW2 surplus in the junk room at Marin Radio Supply in San Rafael, CA, and the rest were painstakingly acquired over about a year's time, using the few dollars I was able to earn doing yardwork and as a substitute paperboy.  The transistors were not in the junk room, of course, and the owner, Dan Olivet, did not stock them, but he special ordered RCA "SK series" replacements for me.  The transmitter was an Ameco AC-1 (6V6 crystal oscillator, 8 watt output) into a 40 meter dipole, the dummy load was a ~ 10 watt light bulb, and the antenna TR switch was a double-throw knife switch.  I remember using the output of the transmitter as a "calibration marker" for the receiver.

Making that first radio contact was probably the high point of my childhood.

Thank you for posting this homebrew project, and your extraordinary photo documentation.

-- Paul AA6AJ
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G3EDM

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RE: "A Three-Transistor Receiver for the Beginner" ARRL 1968 -- Build
« Reply #35 on: January 26, 2014, 05:34:58 AM »

I made my first QSO as WN6GZS in October or November 1970 using this receiver, with W6MJO and WN6ICQ about a mile away.  

[snip...]

Making that first radio contact was probably the high point of my childhood.

Thank you for posting this homebrew project, and your extraordinary photo documentation.

-- Paul AA6AJ

Thank you for the kind comments!

It's great to hear from someone who actually conducted QSOs with this equipment.

Coming up in the next few months: I will be building the 2-tube transmitter that ARRL matched with that receiver. I will try to document that building process in the same way.

I'm also working on my first "proper" antenna (a monoband 40m dipole probably).

And still working on learning Morse ... it's going quite well but fairly slowly.

Then, it will be time for my first-ever QSO, which could turn out to be a high point of my middle age, eh?

73 de Martin, KB1WSY


« Last Edit: January 26, 2014, 05:37:10 AM by KB1WSY »
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AA7EE

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RE: "A Three-Transistor Receiver for the Beginner" ARRL 1968 -- Build
« Reply #36 on: June 29, 2014, 12:36:58 PM »

Wow Martin - there aren't many people around constructing radio equipment like this these days. Your dedication, commitment, and workmanship are outstanding. Thank you so much for taking the time to document this, and to post all the really detailed and well-taken photos.

Have you thought about contacting the author of the original article? He's still listed in QRZ.  I bet he'd be as pleased as punch to know that someone faithfully followed his original design, 46 years later.

Truly great stuff - I now pronounce you a true ham!

Dave (another ex-Brit)
AA7EE (formerly G8RYQ and G4IFA)
« Last Edit: June 29, 2014, 12:47:12 PM by AA7EE »
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G3EDM

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RE: "A Three-Transistor Receiver for the Beginner" ARRL 1968 -- Build
« Reply #37 on: June 29, 2014, 05:03:24 PM »

Wow Martin - there aren't many people around constructing radio equipment like this these days. Your dedication, commitment, and workmanship are outstanding. Thank you so much for taking the time to document this, and to post all the really detailed and well-taken photos.

Thank you!

Have you thought about contacting the author of the original article? He's still listed in QRZ.

Yes, but there is no email, from what I remember. So I wrote him a snail-mail letter, last summer. Didn't hear back, unfortunately.

73 de Martin, KB1WSY
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VU2NAN

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RE: "A Three-Transistor Receiver for the Beginner" ARRL 1968 -- Build
« Reply #38 on: June 30, 2014, 12:16:47 AM »

Hi OM Martin,

Hats off to you for your dedication. The results speak for themselves.

73,

Nandu.

W7UUU

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RE: "A Three-Transistor Receiver for the Beginner" ARRL 1968 -- Build
« Reply #39 on: July 07, 2014, 10:50:32 AM »

Hi Martin - only just now found this thread... WONDERFUL workmanship!
I do hope  that we can meet up when I come out to Boston soon - I'd
really love to see that in person and hear it on the air!

Dave
W7UUU
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My site: www.W7UUU.net - "it's not all about yew, ewe, you!"

G3EDM

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RE: "A Three-Transistor Receiver for the Beginner" ARRL 1968 -- Build
« Reply #40 on: July 07, 2014, 10:56:46 AM »

Hi Martin - only just now found this thread... WONDERFUL workmanship!

Thank you Dave. That receiver is my little joy (well, my second-ranking little joy; mustn't get into trouble here). It's as wide as a barndoor, but very sensitive and just immense fun to operate. Mind you, it's pretty much the only receiver I've got, and it's probably just as well I don't have a "better" one for comparison, at least not yet! By now, I've probably logged a hundred hours monitoring the ham bands with this primitive set.

Of course, it isn't "finished'" yet. I built a cabinet because there was a hum issue in my shack, and the cabinet solved that problem 100 percent. Then I started adding a speaker and an extra audio amplifier so that I could "show off" the radio to non-hams without headphones, but just sorta got stuck in the middle of that project.

When is a homebrew project "finished"?

73 de Martin, KB1WSY
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G3RZP

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RE: "A Three-Transistor Receiver for the Beginner" ARRL 1968 -- Build
« Reply #41 on: July 07, 2014, 12:51:23 PM »

>When is a homebrew project "finished"?<

Something between 'sometimes' and 'never'.
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KJ6ZOL

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RE: "A Three-Transistor Receiver for the Beginner" ARRL 1968 -- Build
« Reply #42 on: July 13, 2014, 06:15:59 PM »

I looked up this book on Ebay, and apparently 1968 was the first year of the three transistor rx discussed in this thread. Somebody is selling the 1967 book, and that book apparently has a two tube rx in it. I was thinking of buying a copy of the book the OP has and making a run at putting together the rx, albeit with modern parts. I wonder if the 1971 or 1974 editions would have this same rx in there.
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G3EDM

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RE: "A Three-Transistor Receiver for the Beginner" ARRL 1968 -- Build
« Reply #43 on: July 13, 2014, 06:53:19 PM »

I looked up this book on Ebay, and apparently 1968 was the first year of the three transistor rx discussed in this thread. Somebody is selling the 1967 book, and that book apparently has a two tube rx in it. I was thinking of buying a copy of the book the OP has and making a run at putting together the rx, albeit with modern parts. I wonder if the 1971 or 1974 editions would have this same rx in there.

I think you are right. In the years immediately before 1968, the "station" included in the book appears to have been all-tube, including the 1964 and 1967 editions.

As for the three-transistor receiver, it was first published in QST, March 1968 issue. The article is: "A Three-Transistor Receiver: The FET as a Regenerative Detector" by Walter F. Lange, W1YDS -- so that particular solid-state design could not have been published in any books before 1968.

I have the 1956 edition which has a nice all-tube station, including a regenerative receiver and a transmitter, both operating on a single power supply.

The book had long production run. The first ones were in the early 1930s. It looks like the last one was in 1974:



I don't think the "3-transistor regen" lasted very long in that series of books. You can tell from the covers of later editions, which you can view here: http://www.n4mw.com/ARRL/arrl08.htm.

My interest in that receiver is that this particular edition of the book (1968) is the one that got me interested in ham radio, as a 12-year-old!

73 de Martin, KB1WSY
« Last Edit: July 13, 2014, 06:56:38 PM by KB1WSY »
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G3EDM

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RE: "A Three-Transistor Receiver for the Beginner" ARRL 1968 -- Build
« Reply #44 on: August 01, 2014, 06:56:58 PM »

Bump. Imminent project: speaker grille, non-headphone audio monitoring.

73 de Martin, KB1WSY
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