• Analog FM Video requires 20 MHz
• Analog FM can only be Down-Linked on 13 cm and higher bands.
• Analog FM can be Up-linked on 23 cm... and higher bands.
• Analog FM provides good quality Video and Audio.

• DCATV Requires 100 kHz - 500 kHz RF band width (128 - 384 KBPS).
• DCATV can be Up or Down linked on 70 cm.
• DCATV will send a lower quality image at FCIF or QCIF rates of 15 Frames per second.

• Antenna-D: 13 cm.. 20dbic $200
• Antenna-U: 23 cm.. 20dbic $200
• Amp and Preamp: $500
• Rotor System and Tower: $1000
• Radio: $1900
• Transverter: $200
• Video Converter: $200
• Approx.. Cost: $4200
• Doppler RX: 80 kHz
• Doppler TX: 45 kHz

• Antenna-D: 70 cm 12 dbic $200
• Antenna-U: 70 cm, same
• Amp and Preamp: optional
• Rotor System and Tower: $1000
• Radio: $1900
• Transverter: None
• Video Converter H.323: $1000
• Approx.. cost: $4100
• Doppler RX: 20 kHz
• Doppler TX: 20 kHz

• The costs of the two versions are very similar. It is expected the cost of the DCATV converters (H.323 protocol) will drop in price from $500 down to $100 over the next two years. This will make DCATV much less expensive than Analog TV.

• To receive Analog TV on 13 cm, will require the user to compensate for a Doppler frequency shift to 80 kHz. In one minute the Doppler error will cause an 8 kHz frequency shift. Only experienced users with computer control will be able to properly compensate for Doppler.

• To receive Analog TV on 70 cm, you will only need to compensate for a Doppler frequency shift to 20 kHz. One frequency change per minute will be required to receive a solid FM Data signal from ISS.

• Assuming a DCATV 70cm Mono simplex operation. The ISS receiver will include a Doppler correction circuit (AFC). This circuit will be able to compensate for signals errors of less than 5 kHz.
• Pass band Filters will be attached to antenna port to improve signal purity and reduce receiver interference.
• The antenna system should include a Circular polarized 3-6 dbic gain Helix.
• Transmitter output: Adjustable from 5 - 40 watts. For optimum performance the output should be at the 40 watt setting.
• Controller: A modified industrial grade Lap-Top PC will perform all of the control functions, including Video and Audio Compression and De-compression.

• Install and easy to use DCATV system on ISS.
• Design the system for easy access to experience Amateur Radio Stations.
• Video can be either Simplex or Full-Duplex configuration.

• Analog FM Satellite video will require too much Satellite band-width.
• It will be easier to find a radio frequency for DCATV.
• More experienced users will be able to access DCATV.
• DCATV is compatible with LAN.

• The DCATV project is not for beginners, however Video can be saved on Web pages for easy access to Schools.
• ISS will need other Amateur Radio Projects specifically designed for Beginners (2-Meter Mono-Band packet, etc.)

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