circuit & control system design & fabrication – proposed technical club
DESCRIPTION
Circuit & Control System Design & Fabrication – Proposed Technical Club. Room C, Saturday August 16, 2:00 – 4:00. Goals for today. Spend ~20 minutes exploring the kinds of activities such organization could support Group Discussion: Is this a good idea? - PowerPoint PPT PresentationTRANSCRIPT
Circuit & Control System Design & Fabrication – Proposed
Technical Club
Room C, Saturday August 16, 2:00 – 4:00
Goals for today
• Spend ~20 minutes exploring the kinds of activities such organization could support
• Group Discussion: Is this a good idea?
• Gather names of individuals interested in participating on a technical level
• Form a small committee to kick start the group
Albuquerque
Transmitter Hunters
Why are we here?
Why are we here?
Because we have the Knack!
Why are we here?
Because we have the Knack!
Click image to start video
We are proposing the formation of an organization to preserve and celebrate the
knack! An organization that would support learning about and the creation of custom
electronics, radio circuits, and control systems
Why are we really here?
• RF communication devices• uProcessor / FPGA based control circuits• PC Board design and manufacture• Mastering surface mount technology• Microprocessor programming• and more
What would this organization do?
Help people learn about and make -
For Example
A Reflow Oven Project
•Simplifies SMD soldering
•Improves soldering consistency
•Represents a group resource
Scott - KC5VVB
Precise Temperature Control
•Three distinct phases
Block Diagram
•Oven
•AC Relay
•Thermocouple
•PIC
Progress•Output relay working
•AC assembly to be provided
•Thermocouple on hand
To Do
•Complete prototype assembly
•Test temperature control
•Write final code
•Fab PCB
•Complete assembly
Or …
SDR TX Project for ARDFHardware / Software Update
Jerry Boyd, WB8WFK
(Hardware and FPGA VHDL )
Mike Pendley, K5ATM (PIC Software)
August 2008
The Problem
Our Current FOX Boxes are
– LARGE and heavy– Tend to fall out of sync– Limited to 2m FM MCW and 80m CW– Programming switches and radios need to be
adjusted to change frequencies and configuration.
Root Cause of Problem
•All problems can be traced to systems that are wired together using mutable connectors, cables and equipment interconnected to function as an ARDF transmitter
•RF gets into and upsets controller
•Radios are not designed for high duty cycle
•Equipment not designed for this application
•Wires can get caught in equipment duringtransport to location and interruptoperation
•Lots of opportunity for somethingto go wrong
The Solution A Software Defined Radio That can
– Dynamically change frequency and modulation modes– Conserve power during “down” time– Use “real time clock” to stay in sync and “auto recover”
if power is interrupted after sync– Phone home with state of health information– A user interface that is easy to configure– Shielded enclosure that protects all electronics– Radio designed for continuous duty cycle (homing
beacon mode)– Simple alignment that only requires a volt meter, power
meter, and receiver
Software (cont)
For Tracking People on ARDF courses
-Sport ID data packet sent while TX is off cycle
-Panic button located at each control station to request medical assistance
A PIC directly controlling a pair of DDS chips
1st Generation Prototype
2nd Generation Prototype
Signal Processor FPGA ($10 Xilinx chip). FPGA, regulators , clock and boot ROM are only features being used on eval board
Mixer
Class C RF amp
OP amp for D/A, AM Modulator & RF power control
Pre driver
Voltage regulator
2nd generation Block Diagram of today's demo hardware
Software2m (VHF) Transmission
modes to be supported– FM MCW Cont carrier– FM MCW keyed carrier– AM MCW Cont carrier– CW– AM MCW keyed carrier– FM packet (1200 baud)– APRS tracker?
145.565 VHFAM Modulation
HF Modes– 80M CW– PSK31?
HF CW 3.58 MHz
What next
• BASIC concept is verified ! I am happy with signal processor operation– Develop CPU board and User interface
– Develop SPI based interface to signal processor FPGA
– Develop SportIdent and panic button interface
– Field test prototype with all of the above functions
• Design PC boards design to include everything
Demo
• Demonstrate Generation 2 prototype system
Some Other Projects
For More Information ….Come to the club meeting
Or …
K5MJE helps KD5JAB build an Elecraft T1 QRP automatic
antenna tuner
Kit Building Support
Inventory
After Page 11
After Page 14
After Page 14 (bottom)
T1 and T2 Installed
Control Board
Toroids Installed
Control Board Installed
Installed in Case
Or …
Construction of Dale Hunt’s 80m ARDF Receiver Kit
Kevin Nichols, KA7OFR
Why 80m ARDF?
• No (well, much much less) reflections or multipath
• Small antenna & receiver
• Simple to build as a kit
• Transmitters are small
• Fits well with Orienteering
Dale Hunt’s (WB6BYU) 80m ARDF
• Fairly small, hand-held 80m (3.5MHz) ARDF receiver
• Single stage direct conversion type receiver
• Easy alignment
• Described in QST, September 2005
• PCB available from FAR Circuits
80m ARDF Kit Parts
PCB, Silk Screened
Some Helpful Items
Schematic - +5v Reg
Schematic – Audio Amp
+5v Regulator and Audio Amp
Schematic - VFO
VFO
Right on Frequency
Winding Torroid TransformerPCB Almost Finished!
A Metal Case
Wooden Loop Antenna Holder
Schematic – Loop Antenna
Threading the Loop
Schematic – Sense Antenna
Sense Antenna
Sense Antenna
Wiring the Front Panel
Ready to Close ‘er Up
The Finished Product!
• Hold a minimum (perhaps no) business meetings
• Periodic formal meetings that would feature one or several technical talks given by members on current or proposed projects
• Support group buys of components and kits
• Be a source of shared resources
• Coordinate classes on various technologies – e.g. microprocessor programming, schematic capture, PCB layout, antenna design, etc.
What would this organization do?
Goals for today• Spend ~20 minutes exploring the kinds of activities the
organization could support
• Group discussion: Is this a good idea?
• Gather names of individuals interested in participating on a technical level
• Form a small committee to kick start the group
– Group structure – independent or a SIG associated with an existing club
– Name of the group
– Frequency and location of meetings
– Other unavoidable administrative stuff
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