Thor Broadcast F-RF-1550-Tx-8mW 1550 nm CATV RF over Fiber Transmitter | Direct Modulated with AGC | EDFA Compatible

A 1550 nm CATV Transmitter

Operating in the C-band changes what a transmitter can do, because 1550 nm signals can be amplified optically. The Thor F-RF-1550-Tx-8mW is a directly modulated transmitter for television RF that works at 1550 nm, making it compatible with erbium-doped fiber amplifiers. A signal can therefore be boosted and fanned out to many receivers, which suits larger FTTH and campus CATV networks rather than single point-to-point links.

Direct Modulation with Gain Control

The unit converts incoming RF directly into optical RF, with automatic gain control holding levels stable as the headend output varies. Line width is under 1 MHz FWHM, extinction ratio above 20 dB and equivalent noise intensity below -160 dB/Hz. Link performance is specified at CNR above 50 dB over 10 km of fiber, CTB below -63 dB and CSO below -57 dB, with SBC restraint above 17 dBm for stable long-haul operation.

RF Connection and Band Flatness

RF input is a single 75 ohm Type-F connector at an AGC-managed level of 11 to 29 dBmV, and optical return loss is above 55 dB. Flatness is held within 0.75 dB from 45 to 862 MHz. Thor stresses that the optical port should be connected using SC/APC angle-polished connectors, and fiber terminated in flat PC connectors needs a PC to SC/APC jumper before the amplifier chain is brought into service.

Rack Format and Operating Limits

The transmitter occupies a 19 by 10 by 1.75 inch chassis and weighs 2.5 kg, mounting in a standard headend rack beside the EDFA it feeds. Operating temperature is 0 to 45 degrees C, so a ventilated or cooled equipment room is assumed. Where the output drives an amplifier, keep the patch between transmitter and EDFA short and clean, since connector loss at this point affects the entire downstream split.

Output Options in the Series

Thor lists the 1550 nm series as F-RF-1550-TX-2mW at +2 dBm, F-RF-1550-TX-4mW at +4 dBm, F-RF-1550-TX-8mW at +8 dBm and F-RF-1550-TX-16mW at +14 dBm output, so output power can be matched to the link budget and amplifier design. Pair the transmitter with a Thor EDFA where high split counts are needed, and choose the output level once the loss budget for the network is known.