Crystal Radio, History, Design, Contesting

[@carlcleary548]

I remember crystal radio my friend and I used to build a radio i love to listen to it back in my days when i was younger back in my early 40s😊

[@TravisTellsTruths]

Best video on crystal radios I've found so far. Amazing stuff. I'm working with wireless electricity.

[@craigcampbell7638]

Mr Day, this video was exceptional and demystified crystal radio systems very well. It has inspired me to build one myself

[@jamesmiller4184]

Gee-whiz !! Never knew all this crystal set excitement and competition existed ! The history and present goings-on of it seem just past-splendid ! One thing I see here is missing (!?!) tho, and that I can supply ! This next transformation 'phase' seems promising plus novel ! This channel is just 'the bees' knees' plus 'the cat's meow' combined, so as of this moment at least, I am its new sub ! Thanks a bunch for it, Mr. David Day !

[@australischemediengemeinschaft]

Für diesen wertvollen Filmbeitrag vergeben wir von maximal 10 erreichbaren Bewertungspunkten: 10. Sehr geeignet für Bildungseinrichtungen.

[@thierrycopuse9889]

Thanks for the video. It reminds me the hours of fun listening to self built receivers when I was a teen and, why not, builing a crystal set again!

[@johnwest7993]

A very well done presentation. Thank you. I now live about 40 miles from NIST station WWVB, but when I lived in MI I built a 3' diameter Styrofoam coil form that I wound with 35 lbs of 8 gauge copper wire coupled with a very large air-variable capacitor to act as a high Q antenna for WWVB. To reduce noise, I put the coil in a basement that lacked electrical wiring. It received WWVB beautifully. Extremely high Q resonant circuits are an almost magical thing, as Nick Tesla learned many years ago.

[@tucker934]

This is also what most seem too not check out, my first crystal set worked but not well at all with the 2 kohm Brandes matched tones I got. I skipped the most important part really, I didn’t even shot for the highest Q I could have gotten just went for it. It works with a high gain amplifier so I was happy with just that! Soon I plan to push for High Q

[@maikerumine]

Only at 11 min and loving this enough to share! Thank you so much for your time and love for XTAL RF. :)

[@trailingfrog]

Ok, thanks very much for your reply and results of your experiments.

[@Steven-re7xt]

Crystal radio was a right of passage. When I got to my army classes. I got as sack w/ parts. Radio So as i waited for the classes. I was to assemble this kit. And be creative. So as I advanced to microwave and multiplex modes I grew out of my kit. But it taught me about soldering, coil winding, and antenna math. A good return for students. Still have one around and at ft hood Texas I got wjr Detroit Michigan and listened to several foot ball games over the years tks om good show. odn-1

[@gunnarisaksson8677]

🎉😂😂😂😂😂😂😂😂

[@RadioHist]

VERY nicely done presentation.... 50+ years ago I could have fun with some crystal set DXing. The local station on 1060 went off at sunset. Eventually two other stations came on the air and run 24/7 except for Sunday at midnight once a month. My house is 0.9 and 1.6 miles between 4 & 5 KW stations on 1060 and 1190.... Tried dual traps and a few other things, but the stations still are deal killers.... Consider yourself lucky.... For those in a more RF friendly environment that have never given crystal set building a try and then graduate to higher performance, I can testify that it can be a fun challenge....

[@erikburman530]

Thank you! Fantastic introduction!

[@ingussilins6330]

Thanks! Very interesting crystal radio circuits. I made TRF receiver with earth battery - earth spike antenna. Circuit runs with 0,6V.

[@trailingfrog]

Thank you for the concise and clear explanations.

[@baikushex0et682]

Hello You can view my simple crystal radio from my small apartment in Bishkek kyrgyzstan Just click my user name

[@joeblow8593]

Really good presentation. I had a Remco crystal radio years ago

[@AymanFakri-ou8ro]

very interesting, thank you!

[@trcwm]

Great video! Hope you have some more of these in the pipeline 🥳

[@maikerumine]

16:00 is the BEST idea, man! KUDOS!!!!

[@andrewandrosow4797]

Hello! I achieved the best sensitivity - when I used a RF mosfet, for example BF998 as a synchronous detector. A gate was connected to "hot" wire of coil (antenna), a drain to 1/4-1/5 part of windings. A drain connected to RF block capacitor 0.02micro Farads, and to 250Ohm earphone - through an electrolytic capacitor.

[@Srinathji_Das]

Awesome video!! 👍 ❤

[@maikerumine]

30:00 was another banger! This is great!

[@0zebede]

Thank you for sharing.

[@joeblow9126]

Great video dave !

[@kenschmidt6522]

Grounding through a water pipe was much more reliable back in the day. Now even if the house has metal pipes, the supply up to the house might be PVC or pex.

[@Dark_Matter2]

Thanks 👍. Great Video

[@chuckmaddison2924]

The small improvements in crystal radio do make a big difference. Unlike hifi.

[@greggaieck4808]

David Day I had a cystatal set radio Receiver when I was a kid

[@keithtaylor6259]

I have picked up shortwave with just a simple crystal radio with just a coil variable capacitor crystal germanium diode and crystal earphone

[@acestudioscouk-Ace-G0ACE]

Very thorough and informative, thank-you! 🖕

[@Chiavaccio]

👏👏👏👏👍

[@maikerumine]

42:09 ...... Amazing.

[@ВолодимирМорозов-е2у]

😊

[@greggaieck4808]

David Day this instresing about cystatal seat radio reciver histotory this cool

[@greggaieck4808]

David Day my hobbys are painting pictures and lisining to shortwave and ssb iam thinking about getting my ham license I have 4 shortwave receivers

[@greggaieck4808]

David Day when I had crystal set radio Receiver I hear shortwave on my crystal seat radio Receiver

[@franzliszt3195]

One would think that if you can bias the diode fairly in a contest, then all designs would have bridge rectifiers.?

[@franzliszt3195]

Oh, yes, this is a super great video!

[@greggaieck4808]

David Day when my mom and dad wore alive my dad me and dad build a shortwave radio Receiver from a kit from radio shack

[@trailingfrog]

I've been doing some research on the Selectivity Enhancement Circuit (SEC) mentioned in this video. On this page: www.theradioboard.com/rb/viewtopic.php?t=2989 Dave from "Dave's Crystal Radio" mentions that the 27mH value is not critical. On this page www.hobbytech.com/Practical%20Tips%20for%20Crystal%20Radios.htm Jim suggests a 10mH-27mH choke, and on this page www.hobbytech.com/crystalradio/crystalradio.htm he mentions it should be between 7.5mH - 10mH for maximum performance at the low end of the band. Have you found that 27mH is the ideal value for the choke?

[@baikushex0et682]

10 is more than enough I've tried it and didn't see much if any change with or without rfc

[@daveschmarder-1950]

The 27mH value is not critical. You should be able to use anywhere from 10mH to 47mH. Shortwave chokes such as 2.5mH are not suitable at broadcast band frequencies.

[@trailingfrog]

@@daveschmarder-1950 Thanks Dave. I have learnt a lot from your website. Regards Grant

[@baikushex0et682]

@@daveschmarder-1950 Dave really appreciated all your work Wonderful talent you have I miss your web sites

[@daveschmarder-1950]

@@baikushex0et682 Thanks for the nice comment. My radio websites might not be gone forever. I don't want to be involved in the. hosting of websites anymore. If someone offered to host the sites, I would be interested in uploading them.

[@maikerumine]

40:00 my stylr._ :) The Franken Class

[@y_x2]

Good technical level😅.

[@joeblow9126]

His best was Hawaii to turks and caicos 5600 miles ...

[@KrishnaKrishna-bj7nf]

15:12 my placeholder, i will delete it

[@toml.8210]

Makeradio.com is now gone.