Homebrewing Produced by Al Mecozzi WA8LBZ For the April 5, 2011 Meeting Of the CRES Amateur Radio Club Additional comments provided by Dave Brown K8AX
The goals of tonight's program are to: Get you Interested in homebrewing your own equipment. Explain the various steps of the homebrewing process. Provide sources of obtaining components. Outline the tools needed to homebrew.
A lot of the information provided in this program applies to kit building. Here are the basic differences between homebrewing and kit building. In homebrewing, you are responsible for all facets of the process. In kit building, all facets of the process are have been determined for you.
Homebrewing... What does homebrew mean? According to the New World Dictionary, Second College Edition Homebrew: n. an alcoholic beverage, such as beer, made at home. According to Wikipedia Homebrew: is an Amateur radio slang term for home-built, noncommercial radio equipment.
Homebrew: is an Amateur radio slang term for home-built, noncommercial radio equipment. Notice the word designed does not appear in the definition. This means that your homebrew project can be a device that you designed or a device you saw in a QST magazine or other source. It may be that you want to alter the design of a device you have seen somewhere.
Why would you want to build your own equipment? The equipment you want does not exist. The challenge of building your own equipment. To learn construction techniques. If you can build it, you can repair it. Sometimes it is cheaper to build than it is to buy. Because it is fun!
After deciding on the device you want to build, develop an outline of the steps you will follow in building the device. List the features you want the device to have.
LIST FEATURES In this example, the features listed are for an ON AIR sign a ham built. The sign must work without a direct connection to transmitter. The sign must turn on when RF is present. The sign must turn off when RF is not present. The sign must work for all modes of operation.
After deciding on the device you want to build, develop an outline of the steps you will follow in building the device. List the features you want the device to have. Make a schematic diagram of the device.
MAKE A SCHEMATIC DIAGRAM Power Supply Considerations Before making a schematic diagram of the project, the type of power supply to be used must be determined. In this example, the device requires +9 VDC unregulated and +5 VDC regulated. Is the device to be used in the shack, in the field or both? If the device is expected to draw less than 50 ma, an internal battery is a good choice for the power supply, for shack and field use. If the device is to be used in the shack, there are a number power supply choices that can be used.
MAKE A SCHEMATIC DIAGRAM Power Supply Considerations This is a very versatile power supply. The input can be supplied from... A 12 VDC battery. A 12-13.8 VDC power supply. A 120 VAC to 12 VAC wallwort (adapter).
MAKE A SCHEMATIC DIAGRAM In this example, two schematic diagrams are shown. One is hand drawn and the other is produced with a computer program. There are a number of computer programs that are designed to make schematic diagrams. Some of the programs will use the schematic diagram it produces to generate the information that can be used to get a printed circuit board (PCB) made. Some of these programs can be used to make parts lists and functional block diagram.
MAKE A SCHEMATIC DIAGRAM Hand Drawn
MAKE A SCHEMATIC DIAGRAM Computer Drawn
After deciding on the device you want to build, develop an outline of the steps you will follow in building the device. List the features you want the device to have. Make a schematic diagram of the device. Determine the wiring method to be used.
WIRING METHOD (Interconnecting Components) Dead bug construction.
DEAD BUG CONSTRUCTION Layout components
DEAD BUG CONSTRUCTION Use glue to hold components in position.
DEAD BUG CONSTRUCTION Interconnect components by soldering
WIRING METHOD (Interconnecting Components) Dead bug construction. Ugly construction.
UGLY CONSTRUCTION
UGLY CONSTRUCTION Ugly Construction Is In The Eye Of The Beholder
UGLY CONSTRUCTION Point-To-Point
UGLY CONSTRUCTION Point-To-Point K8AX
UGLY CONSTRUCTION Don't Do It This Way K8AX
WIRING METHOD (INTERCONNECTING COMPONENTS) Dead bug construction. Ugly construction. Manhattan construction.
MANHATTAN CONSTRUCTION You can also use a punch.
MANHATTAN CONSTRUCTION
MANHATTAN CONSTRUCTION Dah!
MANHATTAN CONSTRUCTION
MANHATTAN CONSTRUCTION
MANHATTAN CONSTRUCTION
MANHATTAN CONSTRUCTION
MANHATTAN CONSTRUCTION
MANHATTAN CONSTRUCTION
MANHATTAN CONSTRUCTION Various shapes and sizes of pads can be used K8AX
MANHATTAN CONSTRUCTION K8AX
MANHATTAN CONSTRUCTION
WIRING METHOD (INTERCONNECTING COMPONENTS) Dead bug construction. Ugly construction. Manhattan construction. Matrix board construction.
MATRIX BOARD CONSTRUCTION
MATRIX BOARD CONSTRUCTION
WIRING METHOD (INTERCONNECTING COMPONENTS) Dead bug construction. Ugly construction. Manhattan construction. Matrix board. Perf board.
PERF BOARD CONSTRUCTION
WIRING METHOD (INTERCONNECTING COMPONENTS) Dead bug construction. Ugly construction. Manhattan construction. Matrix board. Perf board. General purpose circuit boards.
GENERAL PURPOSE PRINTED CIRCUIT BOARD CONSTRUCTION Radio Shack has many types of these General Purpose Printed Circuit Boards.
WIRING METHOD (INTERCONNECTING COMPONENTS) Dead bug construction. Ugly construction. Manhattan construction. Matrix board. Perf board. General purpose circuit boards. Printed circuit boards, homemade or commercially made.
PRINTED CIRCUIT BOARD CONSTRUCTION Interconnection of components happens automatically when components are inserted into the board and soldered. Used for making multiple copies of a device. Use home made or commercially made printed circuit boards.
PRINTED CIRCUIT BOARD CONSTRUCTION Surface mounted devices SMD's
RF DESIGN CONSIDERATIONS Plan the layout of an RF circuit, the physical layout may not follow how the schematic is drawn. Most RF circuits have: Input Output Common ground Be aware: Real capacitors and inductors do not work well over a large frequency range.
RF DESIGN CONSIDERATIONS Layout considerations: RF signal path, avoid inputs and outputs close together. Component placement, RF components versus low frequency and DC components. Keep component leads as short as practical. Best RF ground, continuous copper ground plane which maintains low impedance ground return paths. RF bypass capacitors, use ceramic disc capacitors with short leads or, ideally surface mount capacitors.
RF DESIGN CONSIDERATIONS Concluding recommendations: Divide unit into modules. Maximize circuit ground plane area. Keep inputs and outputs well separated. Keep all connections to ground short and direct. Maximize mechanical strength with frequency determining components. Compact designs are cute, but don't overdo it. Use a mixture of construction techniques. You do not have to totally understand how a circuit works to have success in homebrewing a project.
After deciding on the device you want to build, develop an outline of the steps you will follow in building the device. List the features you want the device to have. Make a schematic diagram of the device. Determine the wiring method to be used. Make a parts list.
MAKE A PARTS LIST
After deciding on the device you want to build, develop an outline of the steps you will follow in building the device. List the features you want the device to have. Make a schematic diagram of the device. Determine the wiring method to be used. Make a parts list. Acquire the components in the parts list.
AQUIRE COMPONENTS Components can be obtained from the Junk Box. The junk box is a ham's stash of components to be used in the future. These parts are obtained: From previous purchases. From hamfests. By begging, borrowing or trading with other hams.
AQUIRE COMPONENTS Components can be obtained from stores found on the Internet and/or from brick-and-mortar stores. Some example of stores frequented by hams are: Radio Shack Most cities have one. However, the types of electronic components they carry has been dwindling over the years. Mouser Electronics An Internet store at http://www.mouser.com/ Digi-Key Another Internet store at http://www.digikey.com/ Futurlec The one I frequent the most is http://www.futurlec.com/ A radio/candy store if you are lucky enough to have one in your area.
After deciding on the device you want to build, develop an outline of the steps you will follow in building the device. List the features you want the device to have. Make a schematic diagram of the device. Determine the wiring method to be used. Make a parts list. Acquire the components in the parts list. Breadboard the device.
BREADBOARD THE DEVICE If possible, breadboard the device to be sure that it is going to work in accordance with your expectations.
After deciding on the device you want to build, develop an outline of the steps you will follow in building the device. List the features you want the device to have. Make a schematic diagram of the device. Determine the wiring method to be used. Make a parts list. Acquire the components in the parts list. Breadboard the device. Determine packaging.
DETERMINE PACKAGING Most hams would agree that the hardest part of of building your own equipment is to determine what packaging to use to house the device. Almost all of the time, the enclosure will be a box. The box can be made of wood, plastic, metal or other material of your choice. The question to be answered at this point is.. Make the box yourself, or Purchase the box.
DETERMINE PACKAGING Examples of metal boxes you can purchase
DETERMINE PACKAGING Purchased metal box The Altoids box
DETERMINE PACKAGING Home made metal box This is one of the easiest to make
DETERMINE PACKAGING Examples of plastic boxes you can purchase
After deciding on the device you want to build, develop an outline of the steps you will follow in building the device. List the features you want the device to have. Make a schematic diagram of the device. Determine the wiring method to be used. Make a parts list. Acquire the components in the parts list. Breadboard the device. Determine packaging. Labeling.
DETERMINE LABELING There are many ways to label your homebrew project. Some of these are... Use a pencil, pen or permanent marker. Use Dymo or other plastic strip labels. Use rub down or pressure sensitive lettering, words and/or symbols. Use a printer to print the desired labels on paper. Cut them out and affix them to your project. The type of labeling you use is only limited by your imagination.
DETERMINE LABELING Some examples of project labeling
DETERMINE LABELING Labeling process for one of my projects
DETERMINE LABELING Labeling process for one of my projects
After deciding on the device you want to build, develop an outline of the steps you will follow in building the device. List the features you want the device to have. Make a schematic diagram of the device. Determine the wiring method to be used. Make a parts list. Acquire the components in the parts list. Breadboard the device. Determine packaging. Labeling. Build and test your project.
SHOP TOOLS Metal drill. Electric is best but a manual drill will work. You will need various sizes of drill bits. Center punch to center drilling, but if you are careful you can do without it. Machine screw taps. A set of 4-40, 6-32, 8-32 and 10-32 taps will be helpful for certain projects. Metal saw. For thicker metals, a band saw is best but you can make do with a hack saw. Screw drivers. Various sizes of flat blade and Phillips screw drivers will be needed. Metal files for smoothing rough edges. Round reams for smoothing drill holes.
SHOP TOOLS (Continued) Metal scribe. Will be helpful for scribing drill locations and cut marks on metal parts. Ruler. For making accurate measurements. Scissors. For cutting paper and thin plastics. Pliers. A set of regular, long nose and diagonal cutter pliers will come in handy. Safety glasses or goggles. A must for eye protection when cutting and drilling metals
ELECTRONIC TOOLS Soldering iron. Used to connect electronic components. Multimeter. There are both analog and digital multimeters. Either will work. Used to measure voltage, current and resistance. This item is an absolute necessity in homebrewing your own equipment. Oscilloscope. Used to verify circuit performance. This item is not a necessity in most cases but can be very helpful and seeing circuit operation. Bench power supply. Used to test and/or power your homebrew project. This can be an electronic power supply or a battery or batteries.
ELECTRONIC TOOLS (Continued) Signal generator. Used to provide test signal inputs to circuits that will require an input to operate. Generators can provide audio or radio frequency signals.
WHERE TO OBTAIN METALS Thin gauge aluminum sheets and angle can be obtained from most local hardware stores including Home Depot and Lowes. Thicker aluminum of various types can be obtained from metal scrap yards. They usually sell the metals by the pound. The one I frequent is located is: Research Alloys Company Inc. 799 Goodale Boulevard (in the rear) Columbus, Ohio Phone: 224-4404
WHERE TO OBTAIN PLASTICS New and scrap plastics (acrylic, Lexan, etc.), thick and thin, in various shapes and forms, can be obtained from: American Plastic Distributing 1015 West Fifth Avenue Columbus, Ohio Phone: 294-5100
QUESTIONS? FURTHER DISCUSSION?