How to push a crystal radio well beyond its extremes ?

Thread Starter

Externet

Joined Nov 29, 2005
2,201
Hi.
How to push a crystal radio design for superb sensitivity, selectivity, and audio output...

What can be done nearing the absurd to achieve extremes, like massive ferrite rods of what kind and dimensions, diametre of coils, selected diode, perhaps a piezo speaker...

Within reality, a truck size coil can be beyond the scope, but hey!, if it justifies having such, worth keeping in mind.
 

Reloadron

Joined Jan 15, 2015
7,501
When I was a kid growing up on Long Island, NY we lived a few miles from the WHLI transmitter site. Using a single 1N34 Germanium diode with a set of WWII surplus headphones and a wet noodle (folded diapole) antenna I could hear WHLI as clear as you could want in my headphones. I thought it was amazing that with no power supply or much anything I could actually listen to a radio station. Never thought about things like tank circuits or tuning around 8 to 10 years old. :) I saw the 1N34 as like a magic rock, like a Cat's-whisker detector.

Ron
 

joeyd999

Joined Jun 6, 2011
5,234
When I was a kid growing up on Long Island, NY we lived a few miles from the WHLI transmitter site. Using a single 1N34 Germanium diode with a set of WWII surplus headphones and a wet noodle (folded diapole) antenna I could hear WHLI as clear as you could want in my headphones. I thought it was amazing that with no power supply or much anything I could actually listen to a radio station. Never thought about things like tank circuits or tuning around 8 to 10 years old. :) I saw the 1N34 as like a magic rock, like a Cat's-whisker detector.

Ron
My first exposure to electronics was a Radio Shack crystal set radio kit when I was 5. Exciting as hell and it got me hooked on electronics for life. From that point forward, if anyone asked me what I was going to be when I grew up, the answer was "electrical engineer".

Unfortunately, I could only pick up one station.
 

joeyd999

Joined Jun 6, 2011
5,234
Oh, and to answer OPs actual question, as stated in the title: "How to push a crystal radio well beyond its extremes?"

Add a JATO to it and light it off...
 

OBW0549

Joined Mar 2, 2015
3,566
When I was a kid growing up on Long Island, NY we lived a few miles from the WHLI transmitter site. Using a single 1N34 Germanium diode with a set of WWII surplus headphones and a wet noodle (folded diapole) antenna I could hear WHLI as clear as you could want in my headphones.
I grew up about 5 miles from the WABC NY broadcasting tower. IIRC at the time, WABC was the most powerful AM station on the East coast. With a setup similar to yours, the sound from the headphones was so loud that I had to unplug them at night so I could get to sleep.
 

MaxHeadRoom

Joined Jul 18, 2013
28,617
One station we had was Rugby Radio transmission facility, Its was a very large, very low frequency (VLF) transmitter, purported to be able to be received 6ft under water anywhere in the world. It came into service on 1 January 1926 and was originally used to transmit telegraph messages to the British Commonwealth, anywhere in the world.
Max.
 

Reloadron

Joined Jan 15, 2015
7,501
I grew up about 5 miles from the WABC NY broadcasting tower. IIRC at the time, WABC was the most powerful AM station on the East coast. With a setup similar to yours, the sound from the headphones was so loud that I had to unplug them at night so I could get to sleep.
Getting off topic but growing up LI NY just a stones throw from "The City" as we referred to it we had three radio stations as kids we listed to. WMCA 570 on your AM dial, WABC 770 on your AM dial, and lastly WINS 1010 on your AM dial. Jones beach was a 15 min thumb ride on the Meadowbrook Parkway. The beaches consisted of thousands of AM transistor radios all tuned to whatever of the three stations the blanket beside you on the beach was tuned to. Growing up LI NY was priceless in the day. We really did have it all. :)

Ron
 

philba

Joined Aug 17, 2017
959
When I was a kid on the Rhode Island shore I had a cat's whisker and hunk of galena that could pick up WABC - it was a straight shot across the LI Sound. My mom was always complaining about the long wire antenna I had hanging out of my window. I probably spent more time trying to find a good contact point on the galena then actually listening to the radio.
 

DickCappels

Joined Aug 21, 2008
10,153
Yes, the MK484 makes a pretty good TRF reciever/IF amp and detector. I have used is as both a receiver in its own right and as a an IF amplifier/detector.

The man who wrote the book on crystal radios was Ben Tongue, of Blonder-Tongue fame (for those from the U.S. who are old enough to remember). Unfortunately Mr. Tongue passed away in 2015 and his website is gone, but luckily it is preserved in the Internet Archive.

https://web.archive.org/web/20161114165001/http://www.bentongue.com/xtalset/xtalset.html
 
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