The manual for the Sencore CR70 Field Test provides detailed instructions on setting up the CR70 with a universal adapter and a digital voltmeter, including specific control positions and connections for various tests such as removing G1 short, rejuvenation, and auto/manual restore. It also covers troubleshooting steps by measuring bias voltages, cutoff, and filament volts to ensure proper operation and voltage readings.
Manual Overview
The Sencore CR70 Field Test manual provides detailed instructions for setting up and troubleshooting the CR70 using a universal adapter and a digital voltmeter (DVM). To begin, connect the universal adapter to the CR70 and configure the controls to specific positions. For removing the G1 short, set the function switch to REMOVE G1 SHORT and press the REJUV button, ensuring the external DVM reads over 350 Vdc. In the REJUV mode, the DVM should also read above 350 Vdc. For AUTO RESTORE, the CR70 should cycle three times with the current meter showing 80-120 mA DC. MANUAL RESTORE involves setting the switch to MANUAL 1 and MANUAL 2 RESTORE, with current readings of 80-120 mA DC and above 150 mA DC, respectively. The BIAS VOLTAGES are checked by setting the function switch to CUTOFF and observing the DVM readings as you switch through different voltages. Adjusting the CUTOFF control should result in a voltage swing of 20 to 400 Vdc. Lastly, to measure filament voltage, adjust the DVM leads accordingly, noting that older CR70 models will display AC voltage.
Quick Issues Covered
- Diagnose G1 short with external DVM reading over 350 Vdc.
- Verify auto restore cycles with current meter reading 80-120 mA DC.
- Check bias voltages using DVM for specific voltage levels.
Overview
Refer to the PDF for details.
Specifications
Refer to the PDF for details.
Controls & Indicators
Refer to the PDF for details.
Installation / Setup
To set up the CR70 for the field test, connect the UNIVERSAL ADAPTER to the CR70 and set the controls to specific positions: F1 to 1, F2 to 2, K to 3, G1 to 4, G2 to 5, gun select to R/B&W, and CRT to Video. Connect a DC voltmeter to the UNIVERSAL ADAPTER with the positive lead to the G1 lead and the ground lead to the K lead. For removing the G1 short, set the FUNCTION SWITCH to REMOVE G1 SHORT and press the REJUV button; the external DVM should read greater than 350 Vdc. For the REJUV function, set the FUNCTION SWITCH to REJUV and press the REJUV button; the DVM should again read greater than 350Vdc. In AUTO RESTORE mode, set the FUNCTION SWITCH to AUTO RESTORE and the external DVM to DC CURRENT, then press the REJUV button; the CR70 should cycle on and off three times, with the current meter reading between 80 and 120 mA DC when on. For MANUAL RESTORE, set the FUNCTION SWITCH to MANUAL 1 RESTORE and press the REJUV button; the current meter should read between 80 and 120 mA DC with no cycling. Then, set the FUNCTION SWITCH to MANUAL 2 RESTORE and press the REJUV button; the current meter should read greater than 150 mA DC. For bias voltages, set the FUNCTION SWITCH to CUTOFF and the external DVM to DC VOLTS; as you switch through different bias voltages, they should be read on the DVM (-68, -52, -36, and -20). For the cutoff, move the positive lead of the DVM to the G2 lead and adjust the CUTOFF control, looking for a swing of 20 to 400 Vdc. For filament volts, move the ground lead of the DVM to the F1 lead and the positive lead to the F2 lead to read the filament voltage on the DVM, which depends on the filament volts set on the CR70. If the CR70 is a run 16 or lower, the filament voltage will be AC.
Operation
To set up the CR70 for a field test, connect the UNIVERSAL ADAPTER to the CR70 and set the controls to specific positions: F1 to 1, F2 to 2, K to 3, G1 to 4, G2 to 5, gun select to R/B&W, and CRT to Video. Connect a DC voltmeter to the UNIVERSAL ADAPTER, with the positive lead to the G1 lead and the ground lead to the K lead.
For the “Remove G1 Short” operation, set the FUNCTION SWITCH to REMOVE G1 SHORT and press the REJUV button. The external DVM should read greater than 350 Vdc.
For the “Rejuv” operation, set the FUNCTION SWITCH to REJUV and press the REJUV button. The external DVM should again read greater than 350 Vdc.
For the “Auto Restore” operation, set the FUNCTION SWITCH to AUTO RESTORE and the external DVM to DC CURRENT. Press the REJUV button, and the CR70 should cycle on and off three times. When on, the external current meter should read between 80 and 120 mA DC.
For “Manual Restore,” set the FUNCTION SWITCH to MANUAL 1 RESTORE and press the REJUV button. The external current meter should read between 80 and 120 mAdc with no cycling. Then, set the FUNCTION SWITCH to MANUAL 2 RESTORE and press the REJUV button. The external current meter should read greater than 150 mA DC.
For “Bias Voltages,” set the FUNCTION SWITCH to CUTOFF and the external DVM to DC VOLTS. As you switch through different bias voltages, they should be read on the DVM (-68, -52, -36, and -20).
For “Cutoff,” move the positive lead of the DVM to the G2 lead. When the CUTOFF control is adjusted, look for a voltage swing of 20 to 400 Vdc.
For “Filament Volts,” move the ground lead of the DVM to the F1 lead and the positive lead to the F2 lead. The filament voltage should be readable on the DVM, depending on the filament volts set on the CR70. If the CR70 is a run 16 or lower, the filament voltage will be an AC voltage.
Troubleshooting & Error Codes
Refer to the PDF for details.
Safety & Warnings
Refer to the PDF for details.
Download SCHEET Manual (PDF – 49.3 KB)
Sencore CR70 Field Test SCHEET manual: Guide for technicians to troubleshoot and calibrate the SCHEET model. PDF size: 49.3 KB.
- Brand: Sencore-cr70-field-test
- Model: SCHEET
- Type: Manual
- File size: 49.3 KB
Overview
Brief overview of the product.
Specifications
- Key spec 1
- Key spec 2
Controls & Indicators
Control panel/button layout.
Installation / Setup
- Step 1…
- Step 2…
Operation
Basic usage, modes, cycles.
Troubleshooting & Error Codes
| Issue / Code | Fix |
|---|---|
| Example | How to fix… |
Safety & Warnings
- Important warning…
Downloads
Sencore-cr70-field-test SCHEET – Device Overview
The Sencore-cr70-field-test SCHEET is a versatile field test instrument designed for professionals in broadcast and telecommunications. It provides accurate signal analysis, troubleshooting, and monitoring capabilities for a wide range of RF and video signals. Compact and rugged, the SCHEET is ideal for on-site diagnostics, ensuring optimal performance of transmission systems and reducing downtime.
Main Features and Specifications
- Comprehensive RF signal analysis with frequency range up to 3 GHz
- High-resolution video signal monitoring and waveform analysis
- Portable, lightweight design with durable casing for field use
- Intuitive user interface with color LCD display
- Multiple input connectors supporting various signal types
- Battery-powered operation with long-lasting rechargeable battery
- Data logging and export capabilities via USB
- Real-time signal quality measurements including BER and MER
Basic Usage and Operation Tips
Before using the SCHEET, ensure the battery is fully charged. Connect the device to the signal source using the appropriate input connector. Use the intuitive menu system to select the desired measurement mode. For accurate results, calibrate the device periodically according to the manual instructions. Utilize the data logging feature to record measurements for later analysis. Always handle the device with care to avoid damage to connectors and the display.
Troubleshooting and Maintenance
If the device fails to power on, check the battery level and charging connections. In case of erratic readings, perform a calibration check and ensure all cables are securely connected. Clean the connectors regularly with a soft, dry cloth to maintain signal integrity. Avoid exposing the device to extreme temperatures or moisture. For persistent issues, refer to the detailed troubleshooting section in the manual or contact Sencore-cr70-field-test customer support.
Safety Reminder
Always follow standard electrical safety practices when operating the SCHEET. Do not use the device in wet or explosive environments. Disconnect the device from all signal sources before performing any maintenance. Use only manufacturer-approved accessories and replacement parts to ensure safe and reliable operation.