• Mouser Electronics at www.mouser.com
• Digi-Key Corporation at www.digikey.com
• Anchor-Electronics at www.anchor-electronics.com
• Jameco Electronics at www.jameco.com
• Amazon at www.amazon.com; almost types of electronic parts and kits as well
• Joe Knows Electronics at http://www.joeknowselectronics.com; other types of electronic parts as well
• Frys Electronics at www.frys.com
• AliExpress at http://www.aliexpress.com
• Linear Integrated Systems, Inc. at www.linearsystems.com
• Mouser Electronics at www.mouser.com
• Digi-Key Corporation at www.digikey.com
• Anchor-Electronics at www.anchor-electronics.com
• Jameco Electronics at www.jameco.com
• Frys Electronics at www.frys.com
• AliExpress at http://www.aliexpress.com
• Amazon at www.amazon.com
• eBay at www.ebay.com
• Mouser at www.mouser.com
• Digi-Key Corporation at www.digikey.com
• AliExpress at http://www.aliexpress.com
• Mouser Electronics at www.mouser.com
• Digi-Key Corporation at www.digikey.com
• Anchor-Electronics at www.anchor-electronics.com
• Jameco Electronics at www.jameco.com
• Mouser Electronics at www.mouser.com for Xicon transformers and coils
• Centerpointe Electronics at www.cpcares.com for Xicon transformers and coils. For IF transformers, search under Xicon I.F. Transformer.
• Mike’s Electronic Parts (Hard to Find Electronics Parts) at https://www.mikeselectronicparts.com for ferrite antenna coils, variable capacitors, and crystal earphones.
• AliExpress at http://www.aliexpress.com search for “diy AM/FM magnet coil,” or ferrite rod or bar (use insulated magnet wire to wind your coil).
• eBay. Search under “ferrite bar” or “ferrite rod”. These blank rods or bars can be wound with wire such as Litz wire to the desired inductance. Typically, the length is at least 2 inches or at least 50 mm.
• Mike’s Electronic Parts (Hard to Find Electronics Parts) at https://www.mikeselectronicparts.com for variable capacitors, antenna coils, and crystal earphones.
• eBay. Search under the terms “polyvaricon”, “variable capacitor”, “tuning capacitor”, or “crystal radio parts”. Note that some of the variable capacitors on eBay are timer capacitors (e.g., < 100 pf).
• AliExpress at http://www.aliexpress.com search for “polyvaricon” or “radio variable capacitor” and some come in two or four sections.
• Amazon at www.amazon.com
• Evil Mad Scientist Laboratories, http://www.evilmadscientist.com/; components such as resistors, LEDs, displays, and also many DIY (do-it-yourself) kits including a discrete transistor version of the 555 timer and 741 op amp by Eric Schlaepfer.
• Elenco, http://www.elenco.com/product/educational; all sorts of educational kits.
• Amazon at www.amazon.com
• Jameco Electronics at www.jameco.com
• AliExpress at http://www.aliexpress.com search for “DIY kits” or “electronic kits”
18.223.106.100