Announcement -- ARRL Homebrew Challenge
We are pleased that the $50 Homebrew Challenge, announced
in Aug 2006 QST and updated in October, has spurred many readers to consider
moving forward to provide an entry. We have received many comments, suggestions
and requests for rules clarification. This Web site will provide the latest
update on decisions taken. In addition, all rules are compiled in this location
for easy reference.
Changes beyond the original posting of this page will be
in bold text.
The Concept
We believe that one impediment for many considering
amateur HF operation is the cost. While in most respects, today's equipment is
a real value compared to commercial equipment of a generation ago, there is not
the alternative of easily adaptable low cost military surplus gear that got
many of us started with HF operation back in the fifties.
One solution is building our own gear. A challenge for a
new ham is finding a design that will be easy to reproduce, work well for a new
operator, be constructed from available parts with available tools and test
equipment and be of reasonable cost. Thus this challenge -- we would like a
member to design and build a complete HF voice and CW station that can be
successfully reproduced for under $50. The winner of this challenge will have
the station described in a QST article and receive a $100 prize, in
addition to the usual payment for our articles.
The Conditions are as Follows:
1. Original Stand-Alone System
- The station must include a transmitter and receiver
that can operate on the CW and voice segments of 40 meters.
- It must meet all FCC regulations for spectral
purity.
- It must have a power output of at least 5 W PEP.
- It must operate from either 120 V ac mains or a
13.8 V dc power supply.
- It can be constructed using ordinary hand tools.
- It must be capable of operation on both voice and CW.
- Voice modulation can be AM, SSB or DSBSC.
- Parts must be readily available either from local
retailers or by mail order. No "flea market specials" allowed.
- Any test equipment other than a multimeter or radio receiver must
either be constructed as part of the project or purchased as part of the
budget.
- Equipment need only operate on a single band, 40
meters. Multiband operation is acceptable and encouraged.
- Frequency control can be by VFO or crystal control.
Some method of variable tuning is encouraged. If crystal controlled, only a
single crystal must be included in the $50.
- The total cost of all parts, except for power
supply, mic, key,
headphones or speaker,
and usual supplies such as wire, nuts and bolts, tape, antenna, solder or glue
must be less than $50.
- Any potentially dangerous voltages or currents must be contained within an enclosure.
2. Additional Computer Operated Option
The other option will allow for a computer and
sound card to be used either as part of the radio processing or display systems
as well as test equipment for alignment and calibration
or programming programmable circuits.
The software must run
on a Windows based PC platform although multi platform support is
encouraged. If sound processing is employed, it must operate with standard Windows
sound hardware. If it works even better with special high-performance sound
cards, that may be noted but we will not include it as part of our evaluation.
The use of standard serial, parallel and USB interface connections is
considered part of the PC, while any special connection hardware must be
provided from the $50 budget.
Common Rules for either category.
- There will be a $100 prize for the winner in each
category.
- The full cost of parts purchased must be included
in the $50. That means that parts should be purchased for single unit price,
unless multiple parts of the same type are used. For example, if seven 0.01 µF
capacitors are used and it makes sense to purchase 10, the price for 10 can be
used.
- The design may include elements from published designs if properly credited.
- To equalize purchase options, parts cost need not
include shipping, handling or sales tax.
- Each entrant must submit a sample of the station
with documentation indicating the source and price of each part used in the
construction. A draft QST article will also be provided including a discussion
of the design with schematic diagram and description of the construction, test
and alignment steps. All portions of the entry must be received at ARRL
Headquarters before Aug 1, 2007.
- The station will first be evaluated by the ARRL
Laboratory in a manner similar to a Product Review of HF transceivers. Entries
determined by the Lab to be acceptable on the basis of FCC spectral purity
requirements will be evaluated by the QST Technical Editorial Staff
based on:
- On the air operability and capability.
- Ease of use by a beginner.
- Elegance and originality of design.
- Success at meeting the spirit of the above
objectives.
- Additional successful entries may be posted to the
ARRL Web site. All winners and runners-up will be required to execute our usual
author agreement providing publication rights to ARRL including any object code for software used.
- Check back frequently for any updates or rule
clarifications. Send questions or suggestions to the undersigned.
- Many thanks to members George Kuehn, N4AUP/9, for
his suggestion and Dave Brainerd, WB6DHW, for the
idea of the computer option.
-- Joel Hallas, W1ZR, QST Technical Editor, w1zr@arrl.org.
Page last modified: 04:28 PM, 24 Oct 2006 ET
Page author: w1zr@arrl.org
Copyright © 2006, American Radio Relay League, Inc. All Rights Reserved.
