Active Combiner
The Contemporary Research QCA9-33, is an active RF combiner that incorporates 8 high-level inputs and 1 low-level input, combining with high isolation as well as amplifying up to a 33 dBmV output level. Created for QMOD HDTV applications, the eight RF inputs typically receive 29 dBmV RF from QMOD HDTV modulators. The ninth input is for up to 19 dBmV RF signals, such as incoming cable feed, a control channel from an ICE-HE Head End control modulator, or any other QMOD or QCA9-33. Up to 8 QCA9-33 combiners can feed a single combiner to deliver up to 76 channels. The extremely low-noise, wideband 860 MHz amplifier compensates for combining losses and adds 3 dBmV of gain, typically supplying a total output of up to 33 dBmV. Employing new RF technology, the QCA9-33 delivers higher isolation, quality, and noise performance over analog-era components; the noise factor is a very low 1.8, four or more times less than other active combiners.