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Crystal Radio Building Contest

Contest Objectives

The objectives of this contest are:

1. To stimulate interest in the design, construction, and building of crystal radios.

2. To provide an opportunity for crystal radio enthusiasts to compare crystal radios.

3. To further the technical development of no-power radio receivers.

4. To have fun.

General Building Category - Radios Entered in the General Building Category may be made in any manner, using any parts desired. It is a certainty that radios made from restored vintage parts will garner a few more points than one made with modern parts, but an ingeniously designed and well made radio using modern parts will hold its own in the scoring. See the guidelines for scoring.

100% Homebrew Building Category - Entries in the 100% Homebrew category radios must not use manufactured radio parts. This does not include the earphone(s). The builder must fabricate the radio parts from household items or raw materials that can be found at the local hardware supply store, or builders emporium, and are not normally thought of as electronic or radio parts. There are no "disqualifying" parts, but more points are awarded for ingenious use of common materials as well as craftsmanship. For example, use of Fahnestock clips would not disqualify a radio as 100 homebrew, but an identical entry that differed only in the fact that the clips were hand made, would win out. Scrounging for parts, like, the wire, or coil core, would help. It is safe to say that a 100% Homebrew entry has little chance of winning if it does not have homemade Capacitors, Resistors, and sports a Home made detector. Scoring criteria for this category is the same as for the General building Category.

Free Style Category The Free Style Category is meant to promote unusual, imaginative, and even bizarre designs. This category is unabashedly inspired by the Australian Crystal Radio Contest, and is meant to encourage the entry of more offbeat, crazy and even downright ugly designs.

General Rules

1. The Crystal Radio Building Contest is open to anyone, anywhere. Multiple entries are permitted. There is no entry fee and no application to fill out. Radios must not have been entered in any other building contest.

2. Entrants may enter their radios in either of two Contest Classes:

a. General Class. This class is for those who don't have the tools and facilities of Argonne National Laboratories or significant hand skills and must use a judicious mix of ingenuity and jury rigging to build their radios. A typical entrant in this Class is an apartment dweller with simple hand tools and small power tools.

b. Master Class. This class is for experienced craftspersons. Typical entrants are persons who make their livings with their hands, such as machinists and cabinetmakers. Serious hobbyists with extensive craftmanship experience also fit into this class.

Each entrant should use his/her best discretion in choosing which class in which to enter.

3. Entries submitted by anyone 18 years old or younger will be judged with all entries and also separately, with an "Under 18" prize being awarded for the entrant under 18 years of age with the highest score. Dad or Grampa can give unlimited advice and critique. They may also help by teaching safe and effective use of tools, but must not touch the radio or radio parts.

4. An entry package should include digital files of the following:

a. A photo or several photos of the crystal radio receiver.

b. An electrical schematic.

c. A written description of the radio including a short story on how the radio took shape. That is, what was the entrant's inspiration to build this particular type of radio, and perhaps some information on how the entrant obtained the parts used in it.

d. Drawings are encouraged but optional.

5. Each entry package may consist of electronic files with text and digital photos.

6. The workmanship of entrants' radios will be judged on merits clearly displayed in their photos and provided in written descriptions and drawings. It is, therefore, important for entrants to submit high quality digital photos with sufficient detail to demonstrate workmanship, and write clear detailed descriptions of the construction methods used. Entrants are permitted to get help from others in photographing and/or digitizing photos of their radios for posting to the Crystal Radio Building Contest Web Site . If you do not have facilities for submitting your entry electronically, and cannot get someone locally to help you, contact Charlie McGinnis at He will scan your photos and post them.

7. Contest entry packages should be sent via e-mail to Charlie:

8. Entries may be submitted any time after the start of the contest and will be posted to the Contest Web site at . Entries must be received no later than the end of February 2001. Early entries are encouraged, because they should inspire more participation. You may improve your entry after you first submit it but must resubmit no later than the end of February 2001.

9. The Judging Committee (listed on the Contest page) will examine entries for adherence to the rules set forth herein.

10. Each judge on the Judging Committee will award points to each entry according to judging criteria listed further on. The highest score an entry can be awarded is 160 points. The entry with the highest number points is the winner. In the event of a tie, the tied entries will be rejudged by the Judging Committee. All decisions of the Judges are final.

Judging Criteria

A. INNOVATION IN RADIO ELECTRONICS DESIGN. An entry having completely new and innovative design involving radio electronics will be awarded up to 20 points.

B. INNOVATION IN MECHANICAL DESIGN. An entry having a completely new and innovative design involving mechanical construction details will be awarded up to 20 points.

C. INNOVATION IN USE OF MATERIALS: Up to 20 points will be awarded to each entry for innovative uses of materials. Entries that are reproductions of existing designs and therefore and may not score high in A. can make up the points here. Use of vintage parts can also add points for this criterion.

D. GENERAL LAYOUT. Each entry will be judged and awarded up to 20 points for tidiness of component layout, ease of access to parts, and ease of adjustment of controls.

E. WORKMANSHIP. Each entry will be judged as carefully as can be reasonably done with the entrant's submitted materials. Judges will be looking closely at the quality of construction of each crystal radio entry with attention paid to woodworking, metalworking, wiring, fabrication, assembly, tidiness of layout, adaptation of materials and parts, finishing/painting. Up to 50 points will be awarded for workmanship as presented in photos submitted by entrants.

F. QUALITY OF SUBMISSION PACKAGE. Each entrant's submission package, including photos, write-up, and drawings will be judged for presentation quality and will be awarded up to 20 points. The more interesting and entertaining the entrant's story, the more points that will be awarded.

G. OVERALL AESTHETIC APPEARANCE. Each entry will be judged and awarded up to 10 points for overall aesthetic appearance. This is a very subjective category and can serve as a tie breaker.

H. PERFORMANCE. Performance is somewhat hard to judge in a contest such as this. This is a BUILDING contest, so most points are determined by how the radio looks and is made. However, the judges will consider performance capability as a factor in A, B, and G. So, if the Radio performs really well, be sure to say so, and give examples. It can't hurt.

Total possible points for all criteria above -- 160


Prizes may be donated by anyone but must be in the hands of a third party, (preferably one of the judges) before its availability can be listed. A list of prizes will be maintained on the Crystal Radio Building Contest page.


This contest has no commercial sponsorship, and any prizes awarded (perhaps only Bragging Rights) will have only token value. Decisions of the sponsor, an unofficial club with no charter, officers, assets, political agenda, dues, scheduled meetings, and which exists only in cyberspace, are final.