Circuit & Control System Design & Fabrication – Proposed Technical Club

1. Circuit & Control System Design & Fabrication – Proposed Technical Club Room C, Saturday August 16, 2:00 – 4:00

2. 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

3. Albuquerque Transmitter Hunters

4. Why are we here?

5. Why are we here? Because we have the Knack!

6. Why are we here? Because we have the Knack! Click image to start video

7. Why are we really here? 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

8. What would this organization do? Help people learn about and make - • RF communication devices • uProcessor / FPGA based control circuits • PC Board design and manufacture • Mastering surface mount technology • Microprocessor programming • and more

9. For Example

10. A Reflow Oven Project Scott - KC5VVB • Simplifies SMD soldering • Improves soldering consistency • Represents a group resource

11. Precise Temperature Control • Three distinct phases

12. Block Diagram • Oven • AC Relay • Thermocouple • PIC

13. Progress • Output relay working • AC assembly to be provided • Thermocouple on hand

14. To Do • Complete prototype assembly • Test temperature control • Write final code • Fab PCB • Complete assembly

15. Or …

16. SDR TX Project for ARDFHardware / Software Update August 2008 Jerry Boyd, WB8WFK (Hardware and FPGA VHDL ) Mike Pendley, K5ATM (PIC Software)

17. 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.

18. 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

19. 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

20. 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

21. 1st Generation Prototype A PIC directly controlling a pair of DDS chips

22. 2nd Generation Prototype Class C RF amp Voltage regulator OP amp for D/A, AM Modulator & RF power control Signal Processor FPGA ($10 Xilinx chip). FPGA, regulators , clock and boot ROM are only features being used on eval board Pre driver Mixer

23. 2nd generation Block Diagram of today's demo hardware

24. Software 2m (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? HF Modes • 80M CW • PSK31? 145.565 VHF AM Modulation HF CW 3.58 MHz

25. 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

26. Demo • Demonstrate Generation 2 prototype system

27. Some Other Projects

28. For More Information ….Come to the club meeting

29. Or …

30. Kit Building Support K5MJE helps KD5JAB build an Elecraft T1 QRP automatic antenna tuner

31. Inventory

32. After Page 11

33. After Page 14

34. After Page 14 (bottom)

35. T1 and T2 Installed

36. Control Board

37. Toroids Installed

38. Control Board Installed

39. Installed in Case

40. Or …

41. Construction of Dale Hunt’s 80m ARDF Receiver Kit Kevin Nichols, KA7OFR

42. 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

43. 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

46. 80m ARDF Kit Parts

47. PCB, Silk Screened

48. Some Helpful Items

49. Schematic - +5v Reg

50. Schematic – Audio Amp