"A Three-Transistor Receiver for the Beginner" ARRL 1968 -- Build

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MARTIN MARRIS:
Greetings all,

You are going to laugh, but I am building "A Three-Transistor Receiver for the Beginner" from the book, "How To Become a Radio Amateur," 1968 edition. After which, I will build its companion transmitter, "A Simple Two-Tube Transmitter," about 10 watts input. I have no illusions as to the performance of this modest and antediluvian station; hopefully I will be able to conduct a handful of QSOs so that I can feel I have finally had the "Novice experience" that I never achieved 45 years ago. After which, I am moving rapidly on to some much beefier homebrew projects that are already partially under way (the "Novice Q5er" tube-based ham converter for the BC-453 military receiver, and the "65 Watts at Low cost" ARRL tube transmitter from the same era).

Pictures of "Chapter One" of my transistor receiver building effort are available at the URL below. This chapter describes the project, prior to build start. For the full effect, click on the first photo, then click the "Full Screen" button at the top left of the screen:

http://tinyurl.com/ktylgzn

New chapters will appear on this thread as I proceed with the project. As a total beginner, I am following exactly the instructions in the ARRL book. I'm sure lots of you will provide advice as to how I should improve this dinosaur, but that comes later, after completion of these first baby steps.

Note: I am not posting the circuit diagram because I need to ask for ARRL permission first. If permission is granted, I will post it.

73 de Martin, KB1WSY

MARTIN MARRIS:
Update: the ARRL has graciously given permission to post the schematic. I've inserted it into the photo gallery, near the beginning of the sequence.

73 de Martin, KB1WSY

James K.Allen:
I don't think anybody will be laughing,many hams started out home brewing their own gear out of sheer necessity and many of  the new appliance operators of today probably wish they had the ability to make some of their own gear and envy those that do.Once you get your receiver built  consider building a cheap HyperMite audio filter kit,I put one on my old Halicrafters S-38 and now can pick out 3 or 4 stations where I could only hear one before.Your Novice type xtmr. will put out a cw note just as well as any QRP type rig today although you may have to spend some time experimenting with the tuning and getting rid of possible chirp.GL and keep us posted.

Peter Chadwick:
Martin,

You are likely to learn far more from building and getting working a discrete transistor (or tube device) than something with one or two integrated circuits.

Go for it!

MARTIN MARRIS:
Quote from: W1JKA on May 31, 2013, 12:10:03 PM

Once you get your receiver built  consider building a cheap HyperMite audio filter kit,I put one on my old Halicrafters S-38 and now can pick out 3 or 4 stations where I could only hear one before.


Thank you for the kind words. One of my projects is the one-tube "Audiofil" from the ARRL book, "Understanding Amateur Radio," 1963. A quote from the book: "The Audiofil has a nominal pass band of 500 to 900 cycles [eds' note: Hertz]; that is, tones above 900 and below 500 will be reduced considerably in amplitude. The pass band is wide enough so that your receiver tuning is not made critical, but the selectivity is such that you'll be able to pull through many signals that otherwise would be hard to copy through interference created by other signals near the same frequency."

Possibly the only challenge is the inductors for that project. It uses a pair of tube audio output transformers, but only their primaries, to function as chokes. "In order to increase the Qs of the chokes, their iron mounting frames should be removed. This is easily done by bending back the small tabs and then slipping the frames off the cores. Cardboard strips replace the frames, to provide a nonmetallic clamp for the cores." As is fairly typical in ARRL publications of the period, no further details are provided except for a photo where -- if you look closely -- you can see that the iron frames have been replaced with cardboard!

Once again, you might ask why I bother with a relatively cumbersome circuit from 50 years ago, but it's a lot of fun and I hope to learn a lot. But it's for later. Having, as yet, built nothing from scratch, I need to focus on one thing at a time!!! (I've built lots of kits and restored several pieces of old equipment, but that doesn't really count!)

73 de Martin, KB1WSY

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