DVB-C FBC: configure eight cable tuners together

An eight-demodulator DVB-C FBC block needs one cable TV feed and one shared configuration. It requires neither SCR numbers nor satellite planes nor eight individual LNB configurations.

Connect the cable correctly

One coaxial feed supplies the block. Numbers 1–8 represent its demodulators, not eight external sockets. Enlarge wiring diagram ↗

Connect the cable TV outlet to CABLE IN / ANT IN. Exact labels depend on the receiver. A LOOP OUT, if fitted, can pass the RF signal to another device. It is not an additional input and does not increase this receiver’s reception capacity. Loop-through operation when powered off depends on the hardware.

HDMI connects the receiver to the television and carries processed video and audio. It does not require an additional RF loop-through cable to the TV. Do not enable power for an active terrestrial aerial on a cable TV connection.

Configure once

Menu → Setup → Reception → Tuner configuration

1. Select the first tuner of the DVB-C FBC block. If eight satellite tuners precede it, this may be I; an independently installed cable block may begin at A.
2. Enable DVB-C or choose Configuration mode = Enabled, where offered.
3. Select the scan method for the cable network: Provider with the correct operator profile, or suitable frequency bands/steps.
4. Adjust network scan, frequency steps, modulations and symbol rates according to the cable operator’s specifications.
5. Save. The other demodulators inherit the block’s shared configuration. Normal tuner selection therefore does not configure them as eight separate reception installations.
6. Start a suitable automatic or manual cable scan. The resulting channel list is shared by the block.

In this mixed installation the cable block follows eight satellite tuners. Its letters are examples, not required names on other receivers. Open original image ↗

The selected cable provider belongs to the example installation. Use your actual operator; there is no need to repeat configuration eight times. Open original image ↗

Which scan option should I use?

Option / method	Purpose
Network ID	Cable-network identifier supplied by the operator; 0 means all networks in the dialog shown. This is neither an IP address nor an SSID.
Country / region	Selects the relevant regional provider profile. The example operator is not a default for other installations.
Force Legacy Signal stats	Uses older driver signal statistics instead of the newer API when specifically required. This display option improves neither signal quality nor tuner capacity.
Provider	Uses frequency definitions for the selected cable network
Frequency bands / steps	Searches ranges when no suitable provider profile exists; extensive searches may take longer
Modulation / QAM	Describes the modulation, such as QAM64 or QAM256; follow the operator’s specification
Symbol rate	Must match the network or individual multiplex
Network scan	May discover additional frequencies from transmitted network information
Automatic scan	Scans using the prepared cable configuration
Manual scan	Checks one known multiplex using its frequency, symbol rate and modulation
CableScan	Separate scan method/plugin with provider-specific parameters; FBC alone does not require it

For detailed dialogs, see DVB-C, automatic scan, manual scan, CableScan and the scan option reference. Scanning once per virtual tuner does not create additional reception paths.

Eight multiplexes are not eight channels

The cable feed contains many frequencies simultaneously. Eight demodulators can process up to eight different QAM multiplexes. Each may carry several services. Another service on an already received multiplex may share its demodulator; another distinct multiplex needs a free one.

This differs from conventional satellite reception: DVB-C does not switch H/V or low/high planes per cable. Shared limitations involving decryption, demux, storage, streaming and playback decoders still apply. Even a normal single DVB-C tuner may receive several services on one multiplex; FBC increases the number of simultaneously received multiplexes.

Check reception and parallel recordings

First check one free-to-air service and its signal quality. Then record free-to-air services on different cable frequencies simultaneously. Only eight different multiplexes test all eight reception paths. Different services on the same multiplex are insufficient.

For interruptions, check cable/outlet condition, level and quality on affected frequencies, provider parameters and decryption limits. An overloaded input can fail despite a high indicated level. This screenshot series shows the genuine configuration of an eight-way cable block; it does not claim a completed eight-way RF/recording test on the cable connection.

Sources: OpenATV visibility and shared cable configuration, NimManager cable-FBC root configuration, Broadcom on cable FBC and multiple QAM demodulators.