Uploaded February 2013 | Updated September 2026, 3 weeks ago
How to make a portable crystal radio using a loop antenna coil and all inside a pizza box. No ground connection or long antenna needed. I go step-by-step into how to make this portable crystal radio. The coil that the tuning/variable capacitor resonates doubles as the antenna by being a very long and large coil. Radio stations are tuned into by adjusting the tuning capacitor and pointing the face of the loop at a nearby radio station. If you don't know where the radio station is, the rotate the coil until something is found.
For this circuit, the diode must be germanium. The following is a partial list of germanium diodes that should work:
1N34A, 1N60, 1N91, 1N119, 1N270, 1N277, 1N283
The following are not germanium diodes and may need a long antenna or a powerful radio station nearby to work:
1N4148 (silicon, found on a lot of circuit boards), B16 (zener diode), 1N5060 (avalanche diode)
The crystal earpiece (piezoelectric earphone) and/or 1N34 germanium diode can be orders from these sources:
scitoyscatalog.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=SC&Category_Code=R
maplin.co.uk/crystalearpiece-3256
Here's my webpage about this pizza box crystal radio:
rimstar.org/science_electronics_projects/loop_antenna_portable_crystal_radio.htm
For how to make a homemade crystal earpiece similar the one used in this video, watch
"Make Crystal Earphone/Earpiece for Crystal Radio - Homemade":
youtu.be/OVapqz4yBCY
For "Crystal Radio Troubleshooting and Tips", watch:
youtu.be/HZZmKZJrIW0
For "How a Rocket Works/Earth to Space Eg SpaceX Falcon 9 and Dragon", watch:
youtu.be/L0AMQ6kRNMA
To see how this crystal radio being played on a speaker using a homemade amplifier, see "How to Make Crystal Radio Amplifier for Speaker":
youtu.be/JtPwxbOgBHw
And for how to make a more common, tunable crystal radio, watch "How to Make/Build a Crystal Radio":
youtu.be/VqdcU9ULAlA
And to see how a crystal radio works, watch "How a Crystal Radio Works":
youtu.be/0-PParSmwtE
To follow me on Twitter:
twitter.com/#!/RimStarz
rimstar.org
Music used throughout:
The Path of the Goblin King Kevin MacLeod (incompetech.com)
Licensed under Creative Commons: By Attribution 3.0
creativecommons.org/licenses/by/3.0
ISRC: USUAN1100873
How to make a portable crystal radio using a loop antenna coil and all inside a pizza box. No ground connection or long antenna needed. I go step-by-step into how to make this portable crystal radio. The coil that the tuning/variable capacitor resonates doubles as the antenna by being a very long and large coil. Radio stations are tuned into by adjusting the tuning capacitor and pointing the face of the loop at a nearby radio station. If you don't know where the radio station is, the rotate the coil until something is found.
For this circuit, the diode must be germanium. The following is a partial list of germanium diodes that should work:
1N34A, 1N60, 1N91, 1N119, 1N270, 1N277, 1N283
The following are not germanium diodes and may need a long antenna or a powerful radio station nearby to work:
1N4148 (silicon, found on a lot of circuit boards), B16 (zener diode), 1N5060 (avalanche diode)
The crystal earpiece (piezoelectric earphone) and/or 1N34 germanium diode can be orders from these sources:
scitoyscatalog.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=SC&Category_Code=R
maplin.co.uk/crystalearpiece-3256
Here's my webpage about this pizza box crystal radio:
rimstar.org/science_electronics_projects/loop_antenna_portable_crystal_radio.htm
For how to make a homemade crystal earpiece similar the one used in this video, watch
"Make Crystal Earphone/Earpiece for Crystal Radio - Homemade":
youtu.be/OVapqz4yBCY
For "Crystal Radio Troubleshooting and Tips", watch:
youtu.be/HZZmKZJrIW0
For "How a Rocket Works/Earth to Space Eg SpaceX Falcon 9 and Dragon", watch:
youtu.be/L0AMQ6kRNMA
To see how this crystal radio being played on a speaker using a homemade amplifier, see "How to Make Crystal Radio Amplifier for Speaker":
youtu.be/JtPwxbOgBHw
And for how to make a more common, tunable crystal radio, watch "How to Make/Build a Crystal Radio":
youtu.be/VqdcU9ULAlA
And to see how a crystal radio works, watch "How a Crystal Radio Works":
youtu.be/0-PParSmwtE
To follow me on Twitter:
twitter.com/#!/RimStarz
rimstar.org
Music used throughout:
The Path of the Goblin King Kevin MacLeod (incompetech.com)
Licensed under Creative Commons: By Attribution 3.0
creativecommons.org/licenses/by/3.0
ISRC: USUAN1100873
