WCARC - DIY Development

Mostly directed to Radio Modules, Weather
and other Sensors, Control and Related Matters

My objective here is to suggest a collection of Basic Building Blocks (B³s) or Units, each as individual as is practical, that can be grouped as desired for a particular project or testing procedure. Then, they can be available at a later date for another project. My 'units' have small rare-earth magnets (usually 1/8 x 1/8 ") glued to their undersides, and the units can be arranged or moved around where needed inside or on the bottom of a cookie baking sheet. And they stay where you want them to be. It is better to buy a new cookie sheet, rather than to steal one from the kitchen. That way you have a nice clean one to work with, and also you don't get into trouble with the 'staff'. For interconnections among units, I use male headers on individual units, and wires with female connectors (cut from female headers) on each end. If you use this approach, you will need to make or buy a considerable bunch of connecting wires of various lengths. The potential for building or acquiring individual units for development and testing flexibility 'on your bench' is enormous. Most experimenters will need only a selection of the units listed here, plus some others as well. This list may appear too inclusive - but when your interests range to weather and environmental instruments, security, control, radio links, communication and recording of data, well ..... Where do you stop ? There is, in fact, no end to the possibilities, but your needs and interests will determine what units will help you to prototype dependable, working systems. My units will be shown as they become available with circuit diagrams and photographs as needed - click on the B³ Links under 'Example' in the table below. I would be pleased to have your comments or your suggestions for other units that might be listed here. Graham VE3BYT
Function	Unit	Notes	Example
GENERAL
Master Control	Microcontroller on Carrier/Programming Board	Such as the carrier board for the Basic Stamp II (Parallax, HVW Technologies, etc.) , or for your preferred PIC or other controller. You might have a separate programming unit.	.
Prototyping	Circuit Prototyping Boards - plug-in type	For temporary circuit assemblies. Several of different sizes may be desirable.	.
Primary Power	Wall-Wart, Regulated DC Power Supply, or Battery Pack	You could use a 9 or 12 volt DC plug-in supply. I prefer to use a gel-cell pack with a built-in charger. If you use an AC-sourced supply, you may need to filter the DC output.	.
Batteries	9 Volt Batteries	Holders (clips) for 9 v batteries on a wood or circuit board. A board with 2 batteries will be useful for OP-AMPs requiring both + and - 9 volts.	.
Power for Remote Site	Solar Power System	Solar panel, charge controller, battery.	.
Lots of Juice	DC Voltage Regulator	7805 circuit for 5 volts DC output, with male headers for + and - connections to other boards. You might need + and - 12 volts as well - 7812 and 7912 regulators.	.
Control signals, data, dialing	DTMF Transceiver (dual tone, multi-frequency)	8880 IC on pcb. This could be a daughter board on the microcontroller carrier board.	.
Telephone Access	Telephone Line Interface	For sending control signals, data, alarms, even slow-scan TV pictures on the phone line, and access to the Internet.	.
Internet Access	Server (preferably small)	Formatting information on HTML pages for uploading to the Internet.	.
Data Transmission	Modem	Sending/receiving data.	.
APRS Access	Terminal Node Controller or equivalent	Sending data packets to the amateur radio APRS network.	.
Connecting Remote Circuits	Screw Terminals	12 Terminal Strip on circuit board with male header - for connecting external security circuits, sensors, Dallas Semiconductor 1-Wire network, etc.	.
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INPUT DEVICES
Control Inputs	Switches - momentary pushbuttons, plus slide, toggle or DIP switches	4 of each would be useful, possibly with LEDs to indicate their state, if needed, and pull-up resistors.	.
Commands, Data	Keypad - 4x4 or 4x5	Keypad with encoder - 74C922 or 74C923	.
Audio	Audio Amplifier A	For audio input to radio transmitter, etc.	.
Time, Duration, Alarms	Pocket Watch B Module	Real time clock with time, calendar and alarm functions.	.
Analogue Voltage Measurement	LTC 1298 2 channel 12-bit A/D Converters	Two on pcb, for 4 channels. For HP II receiver RSSI measurement and for certain weather sensors/transducers.	.
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OUTPUT DEVICES
Visual Display	Liquid crystal Display	The 'serial' type uses fewer controller I/O lines and is easy to program.	.
Printer	Interface to Thermal or other Printer for hard copy	Radio Shack TP-10 thermal printer is compact, if you can find one.	.
Audio	Audio Amplifier B	For radio receiver or other audio output.	.
Indicators	LED Indicators	8 or more LEDs with headers and suitable dropping resistors.	.
Control	Relays	Small relays with by-pass diodes, and headers; buffered input if necessary.	.
Power Control	Solid State Relays	For control of motors, lamps, fans, etc., with headers for control inputs.	.
X 10 Control	Powerline Interface TW513 or 523	For X 10 control of lamps and appliances	.
Stepper Motor Control	Interface/Buffer to Stepper Motors	.	.
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RADIO RELATED DEVICES
Milliwatt RF Power	Radio Transmitter Module	Such as the Linx HP II for 902 - 928 MHz, on carrier board with antenna connection, bypass capacitor on Vcc, and DIP switch for frequency selection.	.
More RF Power	Radio Power Amplifier	Such as Linx BBA 519A - 50 milliwatt 902 MHz amplifier - if you need extra range or more power to drive a following amplifier.	.
Radio Receiver	Radio Receiver Module	Such as the Linx HP II for 902 - 928 MHz, as above for transmitter module.	.
Interface - The Radios to the Ether and the Universe	Antennas	Depending on purpose - short or long range, directional or omnidirectional, horizontal or vertical polarization. See the Antennas file on this site. If you are not on the 902 Band 'frames' site, use the link below at the bottom.	.
Indicator for Received Signal Strength	DC Voltmeter 0-3Vdc	Received Signal Strength Indicator meter for HP II receiver. The output voltage response on the RSSI pin is logarithmic, so an A/D converter is needed for more meaningful measurement.	.
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REPRESENTATIVE SENSORS AND TRANSDUCERS
Atmospheric Pressure	Motorola MPX4115AP	Analogue output voltage to LTC1298	.
Relative Humidity	Honeywell HIH3610	Analogue output voltage to LTC1298	.
Wind Speed	Anemometer - test unit	Magnet rotating over reed switch or Hall Effect device - count the pulses in time period.	.
Temperature	.	.	.
Thermostat	.	.	.
Warm Body Intrusion ( for 2 and 4 legged skunks )	Passive IR Detector.	.	.
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