Introduction to Microwave Amateur Radio

1
Introduction to Microwave Amateur Radio

• Steve Kavanagh, VE3SMA
• John Watson, VE3EZP
• 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
Microwave Ham Bands

• 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

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
• Repeater Control and Linking
• 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

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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 gt 30 dB

15
What Kind of DX is Possible ?

• Here are my results with modest gear (CW or SSB)

16
World DX Records
17
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)

18
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)

19
3.4 GHz (9 cm) 5.7 GHz (6 cm)

• 3.4 GHz
• Currently only VE3OIL (Freelton) , VE3TFU
  (Waterford) and VE3SMA (Cambridge) 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)
• VE3OIK has worked over 500 km (West Virginia) on
  this band

20
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

21
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
• above plus VE3VXO (Waterloo), VE3CRU (Whitby),
  VE3EZP (London)
• Water vapour absorption makes 24 GHz more
  difficult.

22
LASER (470,000 GHz !)

• Optical communication is not strictly amateur
  radiobut 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)

23
Simple Wideband FM Gear

• Block Diagram

24
Lake Erie Propagation Magic
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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

26
Lake Erie Propagation Magic

• Some paths worked around Lake Erie

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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)

28
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/Ont
  VHFAssoc_reflector/
• Meetings
• OVHFA Annual Do
• Microwave Update Conference in USA

29
Worldwide Community

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