Optimod-FM 8700i
Optimod-FM 8700i

2017 NAB Introduction!

Optimod-FM 8700i: Specifications

Frequency Response (Bypass Mode; Analog Processing Chain): Follows standard 50µs or 75µs pre-emphasis curve ±0.10 dB, 2.0 Hz - 15 kHz. Analog left/right output and Digital output can be user configured for flat or pre-emphasized output.

Sample Rate: 64 kHz to 512 kHz, depending on processing being performed.

Noise: Output noise floor will depend upon how much gain the processor is set for (Limit Drive, AGC Drive, Two-Band Drive, and/or Multiband Drive), gating level, equalization, noise reduction, etc. It is primarily governed by the dynamic range of the A/D converter, which has a specified overload-to–noise ratio of 110 dB. The dynamic range of the digital signal processing is 144 dB.

Total System Distortion (de-emphasized, 100% modulation): <0.01% THD, 20 Hz - 1 kHz, rising to <0.05% at 15 kHz. <0.02% SMPTE IM Distortion.

Total System Separation: > 55 dB, 20 Hz - 15 kHz; 60 dB typical.

Polarity (Two-Band and Bypass Modes): Absolute polarity maintained. Positive-going signal on input will result in positive-going signal on output when HD Polarity and FM polarity controls are set to POSITIVE.

Peak Control at HD Output: The peak limiter is oversampled at 256 kHz, yielding a worst- case overshoot of 0.5 dB at the analog output and for all output sample rates. (To achieve this performance at 32 kHz output sample rate, it is necessary to set the 8700i’s HD lowpass filter cutoff frequency to 15 kHz.)



Defeatable Analog FM Diversity delay: 0.27 to 16.384 seconds, adjustable in one-sample increments at 64 kHz sample rate to allow the delays of the analog and digital paths in the HD Radio system to be matched at the receiver output. The relative delay between the HD and analog FM outputs stay constant regardless of the structure in operation. The delay can be changed via 8700i PC Remote software, via SNMP, and via Telnet-style (terminal control) commands through the serial and Ethernet ports. Several manufacturers make HD Radio monitors that can adjust the 8700i’s diversity delay via terminal control to compensate for changes in HD delay that might occur elsewhere in the transmission system.

Minimum Processing Delay: Processing structure dependent. Typically 17 ms for normal latency Five-band, 13 ms for low-latency Five-band, 3.7 ms for ultra-low-latency Five- band, and 17 or 22 ms for 2-band, depending on crossover structure chosen. MX presets have approximately 270 ms delay. The multipath mitigator adds 146 ms of additional delay, and can be bypassed in situations like outside broadcasts where talent needs to monitor off-air.  

Analog Audio Input

Configuration: Stereo.
Impedance: > 10kΩ load impedance, electronically balanced1.
Nominal Input Level: Software adjustable from –4.0 to +13.0 dBu (VU).
Maximum Input Level: +27 dBu.
Connectors: Two XLR-type, female, EMI-suppressed. Pin 1 chassis ground, Pins 2 (+) and 3 electronically balanced, floating and symmetrical.
A/D Conversion: 24 bit 128x oversampled delta sigma converter with linear-phase anti- aliasing filter.
Filtering: RFI filtered, with high-pass filter at 0.15 Hz.

Analog Audio Output

Configuration: Stereo. The analog output can emit the analog FM processed signal, the digital radio processed signal, or the low-delay monitor signal. The FM processed signal can be flat or pre-emphasized (at 50µs or 75µs), software-selectable.
Source Impedance: 50Ω, electronically balanced and floating.
Load Impedance: 600Ω or greater, balanced or unbalanced. Termination not required or recommended.
Output Level (100% peak modulation): Adjustable from –6 dBu to +24 dBu peak, into 600Ω or greater load, software-adjustable.
Signal-to-Noise: > = 90 dB unweighted (Bypass mode, de-emphasized, 20 Hz - 15 kHz bandwidth, referenced to 100% modulation).
Crosstalk: <= –70 dB, 20 Hz - 15 kHz.
Distortion: <= 0.01% THD (Bypass mode, de-emphasized) 20 Hz - 15 kHz bandwidth.
Connectors: Two XLR-type, male, EMI-suppressed. Pin 1 chassis ground, Pins 2 (+) and 3 electronically balanced, floating and symmetrical.
D/A Conversion: 24 bit 128x oversampled.
Filtering: RFI filtered.

Digital Audio Input

Configuration: Stereo per AES3 standard, 24 bit resolution, software selection of stereo, mono from left, mono from right or mono from sum.

Sampling Rate: 32 kHz, 44.1 kHz, 48 kHz, 88.2 kHz, and 96 kHz automatically selected.

Connector: XLR-type, female, EMI-suppressed. Pin 1 chassis ground, pins 2 and 3 transformer balanced and floating, 110Ω impedance.

Input Reference Level: Variable within the range of –30 dBFS to –10 dBFS.
J.17 De-emphasis: Software-selectable

Filtering: RFI filtered.

Digital Audio Outputs

Configuration: Two outputs, each stereo per the AES3 standard. The outputs can be set independently to emit the analog FM processed signal, the digital radio processed signal, or the low-delay monitor signal. The FM processed signal can be configured in software as flat or pre-emphasized to the chosen processing pre-emphasis (50µs or 75µs). The HD processing chain receives the output of the multiband limiter and processes it through a look-ahead peak limiter that operates in parallel with the main FM peak limiting system. The HD and FM signals are always simultaneously available. Each output can apply J.17 pre-emphasis if desired.

Sample Rate: Internal free running at 32 kHz, 44.1 kHz, 48 kHz, 88.2 kHz, or 96 kHz, selected in software. (Use 44.1 kHz or higher for best peak control.) Can also be synced to the AES3 SYNC input or the AES3 digital input at 32 kHz, 44.1 kHz, 48 kHz, 88.2 kHz, and 96 kHz, as configured in software.

Word Length: Software selected for 24, 20, 18, 16 or 14-bit resolution. First-order highpass noise-shaped dither can be optionally added, dither level automatically adjusted appropriately for the word length.

Connector: XLR-type, male, EMI-suppressed. Pin 1 chassis ground, pins 2 and 3 transformer balanced and floating, 110Ω impedance.

Output Level (100% peak modulation): –20.0 to 0.0 dBFS software controlled.

Filtering: RFI filtered.

Frequency Response (Digital Audio Output driven by HD Processing Chain):
For output sample rates of 44.1 kHz and above, the frequency response from input to HD-configured output is ±0.10 dB, 2.0 Hz - 20 kHz; flat or with J.17 pre-emphasis applied. The user may specify lowpass filtering to constrain the bandwidth to 15, 16, 17, 18, or 19 kHz.

Ravenna Audio-Over-IP I/O

Compatibility: 100% AES67-compliant.

Configuration: Two L/R stereo inputs and two L/R stereo outputs. The outputs have the same configuration options as the AES3 outputs (above) except for the sample rate.

Sample Rate: Inputs and outputs support 44.1 kHz, 48 kHz, 88.2 kHz, and 96 kHz. Input locks automatically to the incoming sample rate; out sample rate is software-selectable.

Connector: RJ45, dedicated solely to the audio-over-IP connection.

Digital Sync Input

Configuration: Used for synchronization of either or both AES3 signals to an external reference provided at this input.

Sampling Rate: 32 kHz, 44.1 kHz, 48 kHz, 88.2 kHz, and 96 kHz, automatically selected.

Connector: XLR-type, female, EMI-suppressed. Pin 1 chassis ground, Pins 2 and 3 transformer balanced and floating, 110Ω impedance.

Filtering: RFI filtered.

Wordclock/10 MHz Sync Reference Input

Configuration: Accepts 1x wordclock or 10 MHz reference signals, automatically selected. The DSP master clock can be phase-locked to these signals, which in turn phase-locks the 19 kHz pilot tone frequency, facilitating singe-frequency network operation. The digital output sample frequency can also be locked to these signals.

Level: Unit will lock to 1x wordclock and 10 MHz squarewaves and sinewaves having a peak value of 0.5 V to 5.0 V.

Connector: BNC female, grounded to chassis, non-terminating to allow reference signals to be looped through via an external BNC “tee” connector (not supplied).

Composite Baseband Outputs

Number of Outputs: 2 x analog; 1 x AES3 (MPX hardware only)

Subcarrier Modulation Mode: Standard double sideband mode or compatible single sideband/vestigial sideband mode with SSB/VSB crossover at 150 Hz. SSB/VSB mode adds approximately 12 ms of delay to the composite output signal.

Configuration: Two outputs, each with an independent software-controlled output level control, output amplifier and connector.

Source Impedance: 0Ω voltage source or 75Ω, jumper-selectable. Single-ended, floating over chassis ground.

Load Impedance: 37Ω or greater. Termination not required or recommended.

Maximum Output Level: +12.0 dBu (8.72 Vp-p).

Minimum Output Level: –12 dBu (0.55 Vp-p) for 0.5 dB adjustment resolution.

Pilot Level: Adjustable from 6.0% to 12.0%, software controlled.

Pilot Stability: 19 kHz, ±0.5 Hz (10 degrees to 40 degrees C).

D/A Conversion: 24-bit

Signal-to-Noise Ratio: <= 85 dB (Bypass mode, de-emphasized, 20 Hz - 15 kHz band- width, referenced to 100% modulation, unweighted).

Distortion: <= 0.02% THD (Bypass mode, de-emphasized, 20 Hz - 15 kHz bandwidth, referenced to 100% modulation, unweighted).

Stereo Separation (analog outputs): At 100% modulation = 3.5Vp-p, > 60 dB, 30 Hz - 15 kHz. At 100% modulation = 1.0 - 8.0 Vp-p, > 55 dB, 30 Hz - 15 kHz.

Crosstalk-Linear: <= –80 dB, main channel to sub-channel or sub-channel to main channel (referenced to 100% modulation).

Crosstalk-Non-Linear: <= –80 dB, main channel to sub-channel or sub-channel to main channel (referenced to 100% modulation).

38 kHz Suppression: > = 70 dB (referenced to 100% modulation).

76 kHz & Sideband Suppression: > = 80 dB (referenced to 100% modulation).

Pilot Protection: 60 dB relative to 9% pilot injection, ±250 Hz (up to 2 dB composite processing drive).

Subcarrier Protection (60-100 kHz): > = 70 dB (referenced to 100% modulation; with up to 2 dB composite limiting drive; measured with 800 line FFT analyzer using “maximum peak hold ” display).

57 kHz (RDS/RBDS) Protection: 50 dB relative to 4% subcarrier injection, ±2.0 kHz (up to 2 dB composite processing drive)

Analog composite outputs.

Connectors: Two BNC, floating over chassis ground, EMI suppressed.

Maximum Load Capacitance: 0.047µF (0Ω source impedance). Maximum cable length of 100 feet / 30 meters RG–58A/U.

Filtering: RFI filtered.

AES3 Composite Output

Connector: One XLR-type, appearing on breakout cable

Sample Frequency: 192 kHz

Extension to Interim Industry Standard: The composite baseband is internally sampled at 384 kHz and alternate samples are placed on the left and right audio channels. With compatible receiving hardware, this allows the entire baseband frequency range (0 to 99 kHz) to be accommodated without aliasing. If the frequency range of the SCAs applied to the digital output is limited to less than 96 kHz, this is fully compatible and interoperable with the existing system adopted by the industry, which uses only the left channel at 192 kHz.

Subcarrier (SCA) Inputs

Non-Digitized Inputs: 2 x non-digitized analog are summed into the analog composite outputs but do not appear at the digital composite outputs.
Connectors: 2 x BNC, unbalanced and floating over chassis ground, EMI suppressed.

Number of Inputs: 2 x digitized analog. These are summed into the digital composite but do not appear on the analog composite outputs.
Resolution: 16-bit conversion
Connectors: 2 x BNC, appearing on breakout cable.
Impedance: > 600Ω

SCA Sensitivity (all inputs): Variable from 220 mV p-p to > 10 V p-p to produce 10% injection. Sensitivity of analog inputs is screwdriver-adjustable by trim pots that are accessible through holes in the rear panel. Sensitivity of digitizing inputs is adjustable in software.
19 kHz Pilot Reference: Analog SCA2 input jack can be jumpered to provide a 19 kHz pilot reference output or to serve as a second analog SCA input. The phase of the reference signal can be set to 0°, 90°, 180°, or 270° with respect to the pilot tone appearing at the composite output. The default is 0°.

Remote Computer Interface
Supported Computer and Operating System: IBM-compatible PC running Microsoft Windows® Vista/7/8/8.1/10.

Configuration: TCP/IP protocol via direct cable connect, modem, or Ethernet interface. Modem and other external equipment is not supplied.

Serial Connectors: RS–232 port (3) DB–9 male, EMI-suppressed. Serial Connector 1 uses PPP to provide for direct or modem connection to the 8700i PC Remote application. Serial Connector 2 supports communication to a computer or remote control system via simple ASCII commands for administration and recalling presets. Serial Connector 3 is reserved for future developments.

Ethernet Connector: Female RJ45 connector for 10-100 Mbps networks using CAT5 cabling. Native rate is 100 Mbps. Provides for connection to the 8700i PC Remote application through either a network, or, using a crossover Ethernet cable, directly to a computer.

Ethernet Networking Standard: TCP/IP.

Remote Control (GPI) Interface.

Configuration: Eight (8) inputs, opto-isolated and floating.

Voltage: 6 - 15V AC or DC, momentary or continuous. 9VDC provided to facilitate use with
contact closure.
Connector: DB-25 male, EMI-suppressed.

Control: User-programmable for any eight of user presets, factory presets, bypass, test tone, stereo or mono modes, analog input, digital input.

Filtering: RFI filtered.

Tally Outputs (x2)

Configuration: NPN open-collector

Maximum Voltage: 30 VDC positive. Protected against reverse polarity by a diode; do not exceed 50 mA through this protection diode.

Maximum Current: 30 mA; current must be limited externally.


Voltage: 100–264 VAC, automatically selected, 50–60 Hz, 50 VA.

Failover: Two hot-swappable supplies are included with automatic failover.

Connector: IEC, EMI-suppressed x 2. Detachable 3-wire power cord supplied.

Safety Standards: ETL listed to UL standards, CE marked.


Operating Temperature: 32° to 122° F / 0° to 50° C for all operating voltage ranges.

Humidity: 0–95% RH, non-condensing.

Dimensions (W x H x D): 19” x 5.25” x 15.5” / 48.3 cm x 8.9 cm x 39.4 cm. Depth shown indicates rack penetration; overall front-to-back depth is 17.75” / 45.1 cm. Three rack units high.

Humidity: 0–95% RH, non-condensing.

RFI / EMI: Tested according to Cenelec procedures.

Shipping Weight: 40 lbs. / 18.1 kg

Five Years, Parts and Service: Subject to the limitations set forth in Orban’s Standard Warranty Agreement

Because engineering improvements are ongoing, specifications are subject to change without notice.

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