1. Introduction
The CABLETRONIX CT-AMM is a professional-grade, fully agile micro modulator designed for commercial headend systems. It generates an audio and video modulated RF carrier across a wide frequency range, supporting CATV channels 2 to 125 and Off-Air channels 2 to 69. This device accepts standard video sources such as satellite receivers, demodulators, VCRs, DVD players, and TV/security cameras. Its synthesized frequency control ensures high stability, and front panel access simplifies setup and tuning. The CT-AMM is engineered for flexibility in new deployments, system upgrades, and maintenance, eliminating the need for extensive inventories of fixed-frequency spare modulators.
2. Setup
Proper installation is crucial for optimal performance. The CT-AMM requires DC input power of 5V (400mA) and 12V (150mA). It is designed for use with the Cabletronix CTPS-12 power supply and CTRC-12 rack chassis, or compatible third-party power supplies and chassis.
- Video Input: Connect your video source to the F-connector input.
- Audio Input: Connect your audio source to the RCA input. Note that the CT-AMM requires a video input to function properly; it cannot be used as an audio-only modulator.
- Power Connection: Ensure the correct DC power supply is connected.
- RF Output: Connect the RF output to your distribution system.
The unit features front panel controls for easy setup and tuning, including channel selection and level adjustments.
Figure 2.1: Front panel of the CT-AMM modulator, showing the display, channel up/down buttons, and A/V controls.
Figure 2.2: Side view of the CT-AMM modulator, illustrating the F-connector video input, RCA audio input, and RF output port.
3. Operating Instructions
The CT-AMM is designed for straightforward operation. Channel frequency information, including FCC offsets, is pre-programmed at the factory. The unit features non-volatile memory, ensuring that your selected channel settings are retained even after a power loss.
- Channel Selection: Use the 'Up' and 'Down' buttons on the front panel to select the desired output channel (CATV 2-125 or Off-Air 2-69).
- Level Adjustment: Adjust the output level and Audio/Video (A/V) ratio using the dedicated controls on the front panel to achieve optimal signal quality.
- Input Requirements: Always ensure both a video and an audio signal are present at the inputs for proper modulation.
4. Maintenance
The CABLETRONIX CT-AMM is a robust device designed for long-term reliability. It requires minimal maintenance. Keep the unit clean and free from dust. Avoid exposing the modulator to extreme temperatures or humidity. There are no user-serviceable parts inside the unit. Any internal servicing should only be performed by qualified personnel.
5. Troubleshooting
If you encounter issues with your CT-AMM modulator, consider the following:
- No Output Signal:
- Verify that the power supply is correctly connected and providing the specified voltage (5V and 12V DC).
- Check all video and audio input connections. Ensure they are secure and correctly terminated.
- Confirm that both a video signal and an audio signal are present at the inputs. The CT-AMM will not modulate if only an audio signal is provided.
- Ensure the selected output channel is within the supported frequency range (CATV 2-125, Off-Air 2-69).
- Poor Signal Quality:
- Adjust the output level and A/V ratio using the front panel controls.
- Check the quality of the input video and audio signals. Distorted input signals will result in distorted output.
- Ensure proper impedance matching (75 Ohms) for all connections.
- Channel Not Changing:
- Verify that the front panel buttons are functioning correctly.
- Power cycle the unit by disconnecting and reconnecting the power supply.
If problems persist after following these steps, contact technical support.
6. Specifications
| Feature | Specification |
|---|---|
| Model Number | CT-AMM |
| Output Frequency Range | 54 – 806 MHz |
| CATV Channels Supported | 2 – 125 |
| Off-Air Channels Supported | 2 – 69 |
| Video Input Connector | F-Connector |
| Audio Input Connector | RCA |
| DC Input Power | 5V (400mA), 12V (150mA) |
| Output Level | +50 dBmV typical (20 dB Adjustable Range) |
| A/V Ratio | -12 dB to -18 dB (± 2dB) Adjustable |
| C/N Ratio | 60 dB typical |
| Broadband Noise | -78 dBc |
| Spurious Output | >60 dB |
| Frequency Accuracy | ±5 kHz |
| Output Impedance | 75 Ohms |
| Output Return Loss | 12 dB |
| Item Weight | 14.4 ounces |
| Package Dimensions | 10.6 x 4 x 1.4 inches |
| Compatible Devices | Cameras, DVD Players, TVs, Video Game Consoles |
7. Warranty Information
This product is provided as described. No additional warranties or guarantees are made beyond those specifically stated in the purchase agreement, warranty policy, and return policy provided at the time of sale. Please refer to your purchase documentation for detailed warranty terms and conditions.
8. Support
For technical assistance, troubleshooting beyond the scope of this manual, or inquiries regarding your CABLETRONIX CT-AMM modulator, please contact the seller or manufacturer directly. Refer to your purchase receipt or the product packaging for contact details.
