|Home:||Projects:||Crystal Shortwave Radio|
|1||Diode||1N34A 1||Radio Shack 276-1123||$ 1.19 pkg 10|
|1||Variable capacitor 2||Dual-range: 40-460 pF/30-156 pF||AES CV300-145||$3.50|
|1||Trimmer capacitor||6-40pF||All Elect. VCAP-14||$1.50|
|1||Ceramic capacitors 3||10 pF, 22 pF, 50 pF||Radio Shack 272-801||$2.49 pkg 100|
|2||Phone jacks||1/8-inch diameter||Radio Shack 274-251||$2.49 pkg 3|
|1||Speaker terminal strip 4||Spring-loaded||Radio Shack 274-315||$ 1.29|
|4||Rotary switches||2-pole, 6-circuit||Radio Shack 275-1386||$1.69|
|1||Slide switch||DPDT||Radio Shack 275-407||$ 1.29 pkg 2|
|1||Enameled wire 5||#22 and #26||Radio Shack 278-1345||$3.99 pkg 3|
|3||Knobs||1.0-inch diameter||Radio Shack 274-416||$2.29 pkg 4|
|2||Knobs||0.75-inch diameter||Radio Shack 274-415||$ 1.89 pkg 4|
|1||Project box||7.5" x 4.33" x 2.22" plastic||Radio Shack 270-224||$ 3.49|
|1||Cardboard tube||From paper towel roll|
|1||Epoxy glue 6||JB Weld or similar|
|1||Household glue 7||Elmer's Glueall or similar|
|1||Rubber feet 8||Heavy-duty self-stick||Radio Shack 64-2342||$ 1.49 pkg 8|
|1||Amplified speaker 9||Battery powered||Radio Shack 277-1008||$11.99|
|1||Antenna||6-foot telescoping||Radio Shack 270-1408B||$4.99|
|1||Fuse holder clips 10||(for antenna swivel)||Radio Shack 270-739A||$ 1.19 pkg 2|
1 Any type of germanium diode will work.
2 A variable air capacitor can be scrounged from any old AC/DC superheterodyne AM radio. Use the RF section for the wide range (40-460 pF) and the oscillator section for the narrow range (30-156 pF)
3 Bags of ceramic capacitors are available in large quantities from Antique Electronic Supply and Radio Shack. These capacitors will work fine, but if you buy them in bulk, you may need to identify them using their markings or by reading them with a capacitor meter.
4 The speaker terminal strip is used for the ground and antenna connections, as explained in the building instructions.
5 Enamel-coated wire is available from Radio Shack and other suppliers. Radio Shack part no. 278-1345 is a package of three spools of enameled wire in the following sizes: #22 (gold enamel), #26 (green enamel), and #30 (red enamel), all for $3.99. If you don't see it on display, find it in the catalog and point it out to the clerks so they will order it for you.
6 It's not critical which type of glue you use to fasten the metal frame of the tuning capacitor to the plastic surface of the instrument panel. Epoxy glue (JB weld or similar) will work, and so will silicon-based glues and perhaps others.
7 Elmer's Glueall will work to coat the coils as you wind them. Or, you can use polyurethane varnish to seal the coils.
8 Use four rubber feet to support the cabinet and two rubber feet to fasten the coil to the inside panel of the cabinet.
9 If you choose to use an amplified speaker (highly recommended), use a short coaxial cable terminated with 1/8" plugs on both ends to connect the EconOceanic output to the speaker.
10 One of the fuse holder clips is modified to form a swiveling support for the antenna mast, as explained in the building instructions. To fasten the antenna mast assembly to the cabinet, you'll also need a small screw, rubber washer, metal washer, lockwasher, and nut. If you don't have those items lying around somewhere, your house is cleaner than ours!
Copyright 1997 Walter Heskes and Philip I. Nelson, all rights reserved. This radio construction project, including all descriptions, diagrams, photos, and the underlying electronic design, is published here for the noncommercial use of radio hobbyists. You may print and reproduce these project instructions for your personal use. Commercial use of this material is strictly forbidden.