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My first experience hearing local AM stations was using an actual
chunk of geranium crystal mounted in a blob of lead, that you'd traded some of your best agate marbles for, You used the point of a fine safety pin to scratch around on that chunk of geranium to find the sweat spot, where the station (s) came in the best into your headphones. It didn't seem to be the same spot night after night ! You tried to use the longest wire that you could sneak out your window and up to near the top of the tallest tree in your back yard. Later if you wanted to separate KVOA (1290) ad KTUC (1400), here in Tucson, you had to wind a big coil on an empty round oatmeal box, and try and tune it with a variable capacitor that you'd "rescued" from a defunct radio. This was all mounted on a "bread board", generally a short section of a 1x 6" or a 1x 8"pine or redwood board. Terminal points were metal screws into the board (preferably brass) that the wires were wrapped around ! Gee, that was well over 70 years ago ! Time sure flies when you are having fun ! Chuck,. W7CS ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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Actually, I'm pretty sure the crystal set you are referring to used a piece of galena (a lead sulphide compound), not germanium (and not geranium, which is a flower). Early crystal sets used a piece of springy wire called a "cat whisker" to contact the galena at a sometimes difficult-to-locate crystal, in essence forming a crude point contact (i.e., Schottky) diode. The crystals are small but naturally occurring in the galena. My dad had such a set and I remember using it when I was about six or seven years old (60 years ago for me), but by that time actual germanium diodes were available and my first "real" radio used one of those. 73, Dave AB7E On 7/25/2013 12:22 AM, Chuck Smallhouse wrote: > My first experience hearing local AM stations was using an actual > chunk of geranium crystal mounted in a blob of lead, that you'd traded > some of your best agate marbles for, You used the point of a fine > safety pin to scratch around on that chunk of geranium to find the > sweat spot, where the station (s) came in the best into your > headphones. It didn't seem to be the same spot night after night ! > You tried to use the longest wire that you could sneak out your window > and up to near the top of the tallest tree in your back yard. > > Later if you wanted to separate KVOA (1290) ad KTUC (1400), here in > Tucson, you had to wind a big coil on an empty round oatmeal box, and > try and tune it with a variable capacitor that you'd "rescued" from a > defunct radio. This was all mounted on a "bread board", generally a > short section of a 1x 6" or a 1x 8"pine or redwood board. Terminal > points were metal screws into the board (preferably brass) that the > wires were wrapped around ! > > Gee, that was well over 70 years ago ! Time sure flies when you are > having fun ! > > Chuck,. W7CS ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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When I lived in Africa, Galena was used in the crystal sets which some of my
friends and I built during the very early 1940s. Galena could be found in some outcrops of rock, many of which were present in our garden. Finding the "sweet" spot for the cats whisker could be difficult. Although at home in Nyasaland (now 7Q7) the crystal sets could not receive any signals (no local BC stations), they were responsible for my obtaining a ham licence in 1946. Around 1941 a friend and I used to practice "morse" using a buzzer. We soon discovered that when the key was closed, a raspy buzzing sound could also be heard from a crystal set placed near the buzzer. One discovery led to another, leading to two-way buzzer contacts without interconnecting wires over distances of tens of feet. All came to a rapid halt when the source of strange noises on the family's SW BC receiver was found to be two cub scouts practicing morse! 73, Geoff LX2AO On July 25, 2013 at 9:52 AM, David Gilbert wrote: > Actually, I'm pretty sure the crystal set you are referring to used a > piece of galena (a lead sulphide compound), not germanium (and not > geranium, which is a flower). Early crystal sets used a piece of springy > wire called a "cat whisker" to contact the galena at a sometimes > difficult-to-locate crystal, in essence forming a crude point contact > (i.e., Schottky) diode. The crystals are small but naturally occurring in > the galena. My dad had such a set and I remember using it when I was > about six or seven years old (60 years ago for me), but by that time > actual germanium diodes were available and my first "real" radio used one > of those. > > 73, > Dave AB7E > > > > > On 7/25/2013 12:22 AM, Chuck Smallhouse wrote: >> My first experience hearing local AM stations was using an actual chunk >> of geranium crystal mounted in a blob of lead, that you'd traded some of >> your best agate marbles for, You used the point of a fine safety pin to >> scratch around on that chunk of geranium to find the sweat spot, where >> the station (s) came in the best into your headphones. It didn't seem to >> be the same spot night after night ! You tried to use the longest wire >> that you could sneak out your window and up to near the top of the >> tallest tree in your back yard. >> >> Later if you wanted to separate KVOA (1290) ad KTUC (1400), here in >> Tucson, you had to wind a big coil on an empty round oatmeal box, and try >> and tune it with a variable capacitor that you'd "rescued" from a defunct >> radio. This was all mounted on a "bread board", generally a short >> section of a 1x 6" or a 1x 8"pine or redwood board. Terminal points were >> metal screws into the board (preferably brass) that the wires were >> wrapped around ! >> >> Gee, that was well over 70 years ago ! Time sure flies when you are >> having fun ! >> >> Chuck,. W7CS > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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In reply to this post by David Gilbert
When I was 10 years old (55 years ago), I found a child's picture book
in the library that showed a copper penny, a safety pin, and a wire coil mounted on a piece of wood. I had no particular interest in radio or science at that time but this book appealed to me. I borrowed the book, went home and built the radio. My antenna was just a piece of wire on the floor. The darn thing worked! Now, several decades later I realize that living across the street from the WALL transmitter helped out a lot ;) But that little book and a single afternoon started me off on the greatest hobby in the world. I have since tried reconstructing such a set and never had any luck. It's got to be a real copper penny, the older and more beat up the better, and the safety pin has to find exactly the right spot and make contact "just right." Except if you live across from the transmitter tower in which case you can probably just go outside and listen to your gutter and downspout junction! Stan WB2LQF On Thu, Jul 25, 2013 at 03:52 AM, David Gilbert wrote: > > Actually, I'm pretty sure the crystal set you are referring to used a > piece of galena (a lead sulphide compound), not germanium (and not > geranium, which is a flower). Early crystal sets used a piece of > springy wire called a "cat whisker" to contact the galena at a > sometimes difficult-to-locate crystal, in essence forming a crude > point contact (i.e., Schottky) diode. The crystals are small but > naturally occurring in the galena. My dad had such a set and I > remember using it when I was about six or seven years old (60 years > ago for me), but by that time actual germanium diodes were available > and my first "real" radio used one of those. > > 73, > Dave AB7E > > > > > On 7/25/2013 12:22 AM, Chuck Smallhouse wrote: >> My first experience hearing local AM stations was using an actual >> chunk of geranium crystal mounted in a blob of lead, that you'd >> traded some of your best agate marbles for, You used the point of a >> fine safety pin to scratch around on that chunk of geranium to find >> the sweat spot, where the station (s) came in the best into your >> headphones. It didn't seem to be the same spot night after night ! >> You tried to use the longest wire that you could sneak out your >> window and up to near the top of the tallest tree in your back yard. >> >> Later if you wanted to separate KVOA (1290) ad KTUC (1400), here in >> Tucson, you had to wind a big coil on an empty round oatmeal box, and >> try and tune it with a variable capacitor that you'd "rescued" from a >> defunct radio. This was all mounted on a "bread board", generally a >> short section of a 1x 6" or a 1x 8"pine or redwood board. Terminal >> points were metal screws into the board (preferably brass) that the >> wires were wrapped around ! >> >> Gee, that was well over 70 years ago ! Time sure flies when you are >> having fun ! >> >> Chuck,. W7CS > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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In reply to this post by W7CS
I had an aunt that lived with my grandma. They slept in the same bedroom and she wanted a radio to listen to without bothering her mother. We got a crystal set from Burstein Applebee and I hooked it up for her -- It worked. I think I was in the 6th or7th grade. I seem to also remember a Gillette Blueblade/pencil lead arrangement -- I think it was called a "Foxhole radio." |
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Fox Hole radio... I helped a pre med student build the radio for one of her science projects a few years ago... It worked! And she got an A for her project. She is now a fine Doc with 3 great kids!
Non judgment day is near. On Jul 25, 2013, at 8:27 AM, artus <[hidden email]> wrote: > > I had an aunt that lived with my grandma. They slept in the same bedroom > and she wanted a radio to listen to without bothering her mother. We got a > crystal set from Burstein Applebee and I hooked it up for her -- It worked. > I think I was in the 6th or7th grade. > > I seem to also remember a Gillette Blueblade/pencil lead arrangement -- I > think it was called a "Foxhole radio." > > > > > -- > View this message in context: http://elecraft.365791.n2.nabble.com/OT-Cristal-Sets-tp7577122p7577127.html > Sent from the Elecraft mailing list archive at Nabble.com. > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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When I taught physics, it was a requirement that all my students build a
crystal radio ... great fun by all and a couple went on to get a ham ticket! When I was in 5th grade I built the "Fox hole radio" and never got it to work. An old time gave me this tiny glass tube with two wires sticking out of each end and said, "try this." Worked FB and I hid it under the razor blade ... got a "A" on my science fair project! 73, WA5POK -------------------------------------------------- From: "Philip Townsend Lontz" <[hidden email]> Sent: Thursday, July 25, 2013 10:39 AM To: "artus" <[hidden email]> Cc: <[hidden email]> Subject: Re: [Elecraft] OT: Cristal Sets > Fox Hole radio... I helped a pre med student build the radio for one of > her science projects a few years ago... It worked! And she got an A for > her project. She is now a fine Doc with 3 great kids! > > Non judgment day is near. > > On Jul 25, 2013, at 8:27 AM, artus <[hidden email]> wrote: > >> >> I had an aunt that lived with my grandma. They slept in the same bedroom >> and she wanted a radio to listen to without bothering her mother. We got >> a >> crystal set from Burstein Applebee and I hooked it up for her -- It >> worked. >> I think I was in the 6th or7th grade. >> >> I seem to also remember a Gillette Blueblade/pencil lead arrangement -- I >> think it was called a "Foxhole radio." >> >> >> >> >> -- >> View this message in context: >> http://elecraft.365791.n2.nabble.com/OT-Cristal-Sets-tp7577122p7577127.html >> Sent from the Elecraft mailing list archive at Nabble.com. >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:[hidden email] >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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Hello,
I would like to say thank you to Chuck for the initial e-mail and all the other guys with their comments. I also would like to thank the Elecraft Monitor for allowing the thread to go thru the system. This has brought a lot of memories flooding back to me from my earlier years. I actually have a Crystal Radio which is a Steven Caney design. I purchased this a few years ago when the wife and I were visiting the Science Museum in Baltimore, MD. Unfortunately it was made in China and not a USA produced. But it will still bring back all the fond memories of my early years on when I first became interested in radio. The first radio station I ever copied on the homebrewed crystal radio I made was from Florida. Not bad since I live in Eastern PA. 72 and Thanks, Ron Polityka WB3AAL www.wb3aal.com www.n3epa.org/ K1 - SN 01011 K2 - SN 01392 ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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