Transcript Class 9 - Reocities

Class 10
et198B
ET 198B
Commercial and Amateur (Ham)
Radio
FCC license Preparation Course.
Bill Croghan
WB0KSW
PG-15-6818
Special modes
• Beacons – transmission for the
observations of propagation and/or
reception. Might be from a balloon, hidden
transmitter, or other devices.
• Beacons must still ID, but may be in
automatic operation.
• Maximum Beacon power is 100 watts.
• Beacons are or may be one way
transmissions
EME
• Earth Moon Earth. Also called moon
bounce.
• Typically CW. Rare SSB
• Requires tremendous antennas with high
gain on both TX and RX.
• The moon must be visible.
• Antennas are often “bore sighted” with TV
cameras.
Satellites
• Any class of Ham may use the satellites
• The satellites are not Geostationary.
• As the satellite approaches, Doppler shift
cause the frequency to be higher.
• As the Satellite recedes, the Doppler
makes the frequency lower.
• Apogee is the most distance point from
earth
• Perigee is the closest distance from earth.
International Space Station
• Most if not all of the astronauts are Hams.
• They operate during their free time
• The space station is in orbit and you will only
have 4-6 minutes per pass to communicate.
• They may have many different listening
frequencies but usually only one transmit
frequency.
• The schedules and frequencies are published in
QST magazine.
Telecommand
• A one way transmission to initiate, modify or
terminate functions of a remote device.
• Control of model boats, airplanes, cars etc.
• Control of repeaters, beacons, coffee pots, etc.
• Transmitter must be labeled with call sign and
the station licensee’s name and address.
• Specific frequencies are recommended and
coordinated for large meets and club get
together
Telecommand cont.
• For non- model control.
• Must have a wireline or radio control link.
• A photocopy of the station license must be
posted in a conspicuous place
• The station must be protected do
unauthorized transmissions may not be
made.
Autopatch
• A device that allows amateurs to connect with the
commercial telephone system.
• May be part of a repeater, or a simplex patch.
• Somebody is paying the phone bill.
• Careful to let the other party know they are on the radio.
• The usual rules about commercial use, bad language
and id’s apply.
• If you get put on hold and there is music on hold, hang
Up!
• Remember, the autopatch is not private. Don’t try
special codes, i.e. voice mail passwords.
• Some repeaters cover the tones with other things.
•
Amateur TV
• Fast scan
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6 MHz or more bandwidth.
Like normal TV.
Requires more bandwidth, thus 430 MHz and above
Requires higher power.
• Slow scan
– One new picture every minute or so.
– Can be done at frequencies as voice width channels.
CTCSS
• Continuous Tone Coded Squelch
• Also known as PL (Private Line), Sub
Audible tones
• Must be on the signal into many
transmitters.
• Keeps the receiver quiet unless it’s
present.
• You would not know anyone was on
channel and might transmit over them.
Duplex / cross band operations
• Simplex – Two way on one frequency, one
at a time
• Half Duplex - Two way on two frequencies,
one at a time
• Full duplex – Two way on two frequencies,
simultaneously.
• Cross band – linking from one band to
another. Often full duplex.
Safety
• Electrical danger
• ANY voltage, but especially higher voltages and
higher sources of current.
• Discharge capacitors
• Disconnect mains, NOT just power switch off.
• Use three pin AC plugs whenever possible.
• NEVER cut off the ground pin.
• One hand in the pocket
Main power plug
• Know where your circuit breakers are in
your home
• If you use power strips, utilize the switches
to kill power to the unit.
• NEVER over fuse anything
• Have a good station ground for safety as
well as performance.
Lightning protection
• Assume your antenna will be hit by
lightning
• Assume your AC will bring in lightning
• Assume your telephone will bring in
lightning
• Use surge protection devices.
• $4.00 strips are usually useless, but some
$20 strips even come with insurance.
• Blitz bugs,
Antenna structure installation
• Follow the manufacturers recommendations
• Obey the local zoning/building codes
• Do not run anything through the concrete into
ground.
• Don’t over load
• Examine used tower carefully.
• Consider where it will fall if it falls.
• “LET IT GO !!!!!”
Tower climbing safety
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Generally DON”T
Never climb alone
ALWAYS three point of contact
Use good OSHA approved climbing harnesses
Inspect your harnesses and belts before leaving the
ground.
100% tether.
When working below, hard hat and safety glasses.
If working on the tower with someone else, announce to
the other when you are going to move and what you are
going to do.
Use the safety belts for protection, NOT support.
Next week
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RF exposure and environmental safety
Compliance distances
Biological effects and potential hazards
Routine station evaluations
Midterm test to cover all the questions in
the pool 15-20 questions.
• Following week, Commercial license and
introduction to commercial shortwave and
VHF\UHF monitoring.