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Introduction to Microwave Amateur Radio

Introduction to Microwave Amateur Radio. Steve Kavanagh, VE3SMA April 2008. What are Microwaves ?. Just radio waves with short wavelengths Definition is imprecise, but usually means frequencies above 1 GHz (1000 MHz) Hams sometimes include 902 MHz band Microwaves are fun !. 902-928 MHz

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Introduction to Microwave Amateur Radio

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  1. Introduction to Microwave Amateur Radio Steve Kavanagh, VE3SMA April 2008

  2. What are Microwaves ? • Just radio waves with short wavelengths • Definition is imprecise, but usually means frequencies above 1 GHz (1000 MHz) • Hams sometimes include 902 MHz band • Microwaves are fun !

  3. 902-928 MHz 1240-1300 MHz 2300-2450 MHz 3300-3500 MHz 5650-5925 MHz 10.0-10.5 GHz 24.0-24.25 GHz 47.0-47.2 GHz 76.0-81.5 GHz * 122.25-123.0 GHz * 134-141 GHz * 241-250 GHz * = change in Table of Frequency Allocations – not yet in RIC-2 Microwave Ham Bands

  4. Types of Activity • DXing and Contests • Mostly CW/SSB, some FM on 10/24 GHz, some digital modes • Portable activity is popular • Moonbounce • FM Repeaters • Somewhat rare • 902 MHz & 1.2 GHz • Amateur Television • Lots of bandwidth available • Activity on 902 MHz, 1.2, 2.3 & 10 GHz • Satellites • 1.2, 2.4 & 24 GHz, so far • High Speed Data

  5. Propagation Modes • Line of sight • For gains that do not vary with frequency signal is much lower at shorter wavelengths - repeater/mobile operation works poorly above 2 GHz • But for fixed antenna size signal is proportional to f2 - long distance point-to-point links with directional antennas work at virtually any frequency • Need to avoid blockage by buildings, trees • Reflection paths • Tropospheric scattering, ducting • Rain (and snow) scatter • Moonbounce • No ionospheric propagation, aurora, meteor scatter (so far !)

  6. Equipment • Commercially built transceivers • Kenwood TS-2000X & Icom IC-910H (with optional module) cover 1.2 GHz (multi-mode) • 1.2 GHz FM-only transceivers (and multi-band FM handhelds covering 1.2 GHz) have been made but I am unaware of any current models • ATV gear : PC Electronics makes TV transmitters & receivers for 902 MHz, 1.2 & 2.3 GHz • Advanced Receiver Research TR-10GA & TR-24GA 10 & 24 GHz wideband FM radios (discontinued)

  7. Equipment • Commercially available transverters • Convert a lower frequency rig (usually 28 or 144 MHz) to operate at a higher frequency • 902 MHz to 47 GHz transverters available fully built or as kits from • Down East Microwave Inc. (Florida) • Kuhne Electronic (Germany)

  8. Equipment

  9. Equipment • Homebrew & Surplus • Plenty of scope for the homebrewer who wants a challenge • But often much easier than you might think ! • Some fairly easily converted commercial gear • Possibility of using 902 MHz, 2.4 GHz and 5.8 GHz wireless equipment – a good example is the “Wavecom Jr” 2.4 GHz TV transceiver.

  10. Antennas • Mobile and other omnidirectional verticals • Available from Comet (902 MHz), Diamond (multiband incl. 1.2 GHz) • Yagi • OK for 902 MHz, 1.2 GHz, performance hard to maintain at higher bands

  11. Antennas • Helix • Circularly polarized • Used for satellite work at 1.2 GHz

  12. Antennas • Loop Yagi • Good for 902 MHz to 3.5 GHz • Available from Directive Systems in Maine

  13. Antennas • Horn • Useful from 3.3 GHz up • 10 & 24 GHz horns available from Advanced Receiver Research (CT) • Easy to make

  14. Antennas • Dish • Useful from 1.2 GHz up • Gain often > 30 dB

  15. What Kind of DX is Possible ? • Here are my results with modest gear (CW or SSB):

  16. Canadian DX Records

  17. World DX Records

  18. 902 MHz (33 cm) • 902-928 MHz shared with ISM and unlicensed consumer equipment (mostly cordless phones) – QRM is a reality ! • SSB/CW stations in this area: • VE3BFM (nr. Alliston), VE3CRU (Whitby), VE3OIL (Freelton), VE3NPB (Toronto), VE3TFU (Waterford), VE3SMA (Cambridge) • Propagation similar to 70 cm (430 MHz)

  19. 1.2 GHz (23 cm) • 1240-1300 MHz shared with radar • I occasionally get radar QRM • 1296 MHz SSB/CW stations in this area: • NP4B/VE3 (Hamilton), VE3BFM (nr. Alliston), VE3TFU (Waterford), VE3OIL (Freelton), VE3NPB (Toronto), VE3SMA (Cambridge)

  20. 2.3 GHz (13 cm) • 2.3-2.45 GHz shared with various services. QRM from WLAN and cordless phones to satellite downlinks at 2401 MHz is common. • Can use WLAN (e.g. IEEE 802.11) equipment in amateur service with higher power/bigger antennas than permitted without a licence. • 2304 MHz SSB/CW stations in this area: • VE3CRU (Whitby), VE3OIL (Freelton), VE3NPB (Toronto), VE3TFU (Waterford), VE3SMA (Cambridge) • At least 70 identified stations recently active across Canada (all modes)

  21. 3.4 GHz (9 cm) & 5.7 GHz (6 cm) • 3.4 GHz • Currently only VE3OIL (Freelton), VE3SMA (Cambridge) and VE3TFU (Waterford) active in this area (CW & SSB at 3456 MHz). • 5.7 GHz • Currently only VE3SMA (Cambridge) active in this area (CW & SSB at 5760 MHz). VE3TFU will be on soon. • VE3OIK has worked over 500 km (West Virginia) on this band

  22. 10 GHz (3 cm) • One of the most popular microwave bands • A few dozen southern Ontario hams have been active over the past 20 years on both wideband FM and SSB/CW • Currently active on 10.368 GHz SSB/CW in this area: • VE3CRU (Whitby), VE3NPB (Toronto), VE3FHM (Georgetown), VE3TFU (Waterford), VE3SMA (Cambridge) • Several others on WBFM

  23. 24 GHz • Shared with various services but no QRM problems observed • 24.192 GHz SSB/CW stations in this area: • VE3SMA (Cambridge) • VE3TFU (Waterford) • VE3FHM (Georgetown) is under construction • 24 GHz WBFM activity: • VE3SMA, VE3FHM, VE3VXO (Waterloo), VE3CRU (Whitby), VE3EZP (London) • Water vapour absorption makes 24 GHz more difficult.

  24. 47 GHz • Highest frequency for which commercial equipment is available • Only activity in Ontario has been by visiting Rochester NY area hams • VE4MA was the first ham anywhere to hear a signal on this band reflected from the moon (from RW3BP), and has now made a 2-way contact with him

  25. 76 GHz & Up • Homebrew equipment only ! • No activity yet in Canada, but VE4MA is collecting parts • New allocations shared with radio astronomy – do not expect any QRM !

  26. LASER (470,000 GHz !) • Optical communication is not strictly amateur radio…but it is interesting to play with • Because all frequencies above 300 GHz are allocated to amateurs in the USA it is considered a ham band in the USA and counts in ARRL VHF/UHF/Microwave contests • Gear can be very simple • Transceiver kits available from Ramsey • Must be very careful with safety (potential for eye damage, distracting drivers and pilots)

  27. Simple Wideband FM Gear • Block Diagram

  28. Lake Erie Propagation Magic

  29. Lake Erie Propagation Magic • Long Point (6 ft)-Morpeth (15 ft)...113 km • VE3OIK-VE3NPB/SMA ( 10 GHz SSB) • VE3OIK-VE3CRU (10 GHz WBFM) • Long Point (6 ft)-Wheatley (12 ft)…172 km • Barely able to make contact on 2m CW (25 W each, 5-7 el beams at 10-18 ft) • VE3OIK-VE3NPB/SMA (10 GHz SSB, S-meters pinned !) • Clarke Rd (60 ft)-Morpeth(15 ft)…91 km • Much weaker signals

  30. Lake Erie Propagation Magic • Some paths worked around Lake Erie

  31. Awards and Contests • ARRL VHF/UHF Century Club (VUCC) • Available for each VHF/UHF/Microwave band for working specified number of grid squares (2 longitude x 1 latitude) • Contests involving microwaves: • ARRL VHF Sweepstakes (January) • SBMS 2 GHz & Up Contest (May) • 902 MHz & Up Sprints (May/October) • ARRL VHF QSO Parties (June/September) • ARRL UHF Contest (August) • ARRL 10 GHz & Up Contest (August/September)

  32. Worldwide Community • Internet discussion groups: • WA1MBA Microwave Reflector • See www.wa1mba.org • Ontario VHF Association • www.ovhfa.com , http://home.cogeco.ca/~ovhfa/ • Email reflector: http://groups.yahoo.com/group/OntVHFAssoc_reflector/ • Meetings • OVHFA Annual “Do” • Microwave Update Conference in USA

  33. Worldwide Community • Microwave operators are a fairly small group, and always keen to have more people to work on the microwave bands • I’ve found microwavers are usually helpful and generous with their time, expertise and even equipment • Remember: help is always available to get you going !

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