The manual for B&K Precision Models 480 and 490 Video Display Testers provides detailed instructions for setting up, operating, and troubleshooting the equipment, including safety warnings about the risks of electrical shock when testing cathode-ray tubes. It covers features such as the control panel design for efficient testing, rejuvenation capabilities, and maintenance procedures like fuse replacement and field calibration.
Manual Overview
The B&K Precision Models 480 and 490 Video Display Testers are designed for testing and rejuvenating cathode-ray tubes (CRTs) in various devices. They feature a user-friendly control panel that guides technicians through the testing process, minimizing errors and time. The Model 490 incorporates digital multiplexing for simplified procedures. Troubleshooting involves a sequence of tests including emission, leakage, and shorts removal, with specific controls for adjusting heater, G1, and G2 voltages. The testers provide a rejuvenation function to restore cathode performance, with automatic timing to prevent damage. Calibration is field-adjustable, ensuring accurate measurements. Error diagnostics are facilitated by indicators for shorts and emission levels. Board-level guidance includes detailed control functions and voltage adjustments, essential for precise testing and maintenance. Safety precautions are emphasized due to the high voltage risks associated with CRT testing, advising technicians to disconnect power and treat all equipment as potentially hazardous. The testers are housed in durable cases with storage for accessories, enhancing their portability and convenience in various testing environments.
Quick Issues Covered
- Diagnose CRT power-up failures with Model 480/490 testers.
- Field calibration adjustments for accurate CRT testing.
- Schematics for circuit tracing and troubleshooting.
Overview
The B & K-Precision Models 480 and 490 Video Display Testers are designed to test and rejuvenate a wide range of cathode-ray tubes (CRTs), including both color and monochrome types. The manual covers safety warnings, specifications, controls, operating instructions, theory of operation, maintenance, and warranty service instructions. The testers feature a control panel for guided testing, variable voltage settings, a color tracking feature, and a patented rejuvenation capability. The Model 490 includes additional features such as three precision meters and a simplified life test.
Specifications
- Types of CRT's Tested:
- – Most monochrome, color and projection TV CRT's, video monitor CRT's, and computer terminal CRT's.
- Tests Performed:
- – Emission.
- – Leakage.
- – Tracking (color tubes).
- – Life.
- – Focus continuity (Model 490 only).
- – Shorts removal.
- Restoring Functions:
- – Gun cleaning and balancing.
- – Cathode rejuvenation.
- Meter(s):
- – Model 480: one, 4-1/2", D'Arsonval movement.
- – Model 490: three, 2-1/2", D'Arsonval movement.
- Meter Indications:
- – Emission: 0 to 2 mA.
- – Restoring Current: 0 to 2 scale.
- – Heater Voltage: 0 to 15 V.
- – G1 Bias Voltage: 0 to 100 V (Model 480), 30 to 100 V (Model 490).
- – Power Line Voltage: Good/bad indication (Model 480 only).
- Test Voltages:
- – Heater: 7 to 14V @ 600 mA.
- – G1 Bias: 0 to -100 VDC (Model 480), -30 to -100 VDC (Model 490).
- – G2 Supply: 0 to 450 VDC (Model 480), 0 to 350 VDC (NORMAL on Model 490), 180 to 530 VDC (HIGH on Model 490).
- Accessories:
- – CRT Socket Adapters: Six supplied; optional adapters available for most common TV and monitor CRT's.
- – Set-up Chart: Shows adapter number and heater test voltages.
- Power Requirements:
- – 117 VAC, 60 Hz, 40 Watts.
- – 117/230 VAC, 50/60 Hz versions available for both models.
- Case:
- – Heavy-duty polyethylene with metal frame and removable lid. Storage space provided for cords and adapters.
- Dimensions:
- – 14-3/4 x 11-1/2 x 7" (375 x 292 x 178 mm).
- Weight:
- – Model 480: 11-3/4 lbs (5.3 kg).
- – Model 490: 14-1/2 lbs (6.5 kg).
Controls & Indicators
The front-panel controls and indicators for the Model 480 include:
1. Function Switch: Selects the main operating mode, such as OFF/HTR RANGE, SET HTR, LEAKAGE, SET Gi, SET CUTOFF, READ EMISSION, SET TRACKING, REMOVE SHORTS, CLEAN-BALANCE, and REJUVENATE.
2. RESTORE Pushbutton: Applies restoring voltage between G1 and cathode, and interrupts heater voltage. It is also used for CLEAN-BALANCE and REMOVE SHORTS procedures.
3. TRACKING Control: Varies emission readings of all guns proportionally from zero to full value.
4. G2 Control – BLUE: Adjusts the value of G2 voltage (blue gun) to SET CUTOFF condition of the test.
5. G2 Control – GREEN: Adjusts the value of G2 voltage (green gun) to SET CUTOFF condition of the test.
6. G2 Control – RED/B&W: Adjusts the value of G2 voltage (red gun or B&W (monochrome) tube) to SET CUTOFF condition of the test.
7. Meter: Indicates heater voltage, leakage, G1 volts, emission, tracking, cleaning, balancing, and rejuvenation, depending on the operating mode.
8. POWER Lamp: Indicates power is “on”.
9. Gun Selector Switch: Selects red/B&W, green, or blue gun.
10. G1 VOLTAGE Control: Adjusts control grid bias voltage; range: 0 to -100 VDC.
11. SET HEATER Control: Fine adjustment of heater voltage +2 VAC.
12. HTR RANGE Control: Coarse adjustment of heater voltage with various ranges for different voltages and currents.
Installation / Setup
Refer to the PDF for details.
Operation
Refer to the PDF for details.
Troubleshooting & Error Codes
Refer to the PDF for details.
Safety & Warnings
There is a certain amount of danger from electrical shock if this equipment is used improperly, or from contacting high voltage in the television set, video monitor, computer terminal, etc. in which the cathode ray tube being tested is installed. This instrument is intended for use only by qualified electronics technicians who are trained to work safely in the presence of high voltage. Be alert to the following hazards when using the Model 480/490 CRT Tester/Rejuvenator:
1. An electrical shock causing 10 milliamps of current to pass through the heart will stop most human heartbeats. Higher voltages pose a greater threat because they can more easily produce a lethal current. However, voltage as low as 35 volts de or ac rms should be considered dangerous and hazardous since it can produce a lethal current under certain conditions.
2. Many television sets and other devices with CRT’s are transformerless “hot chassis” powered, where one side of the ac power line is connected directly to the chassis. If such equipment does not have a polarized power plug to prevent insertion the “wrong” way, a serious shock hazard exists if the chassis is touched. Additionally, damage to the CRT tester/rejuvenator or the TV set or monitor could result. Unplug any “hot chassis” TV set or monitor from its ac outlet before attempting to access the CRT (just turning off the set does not eliminate the hazard). To be on the safe side, treat all equipment as “hot chassis” type unless you are sure it has a floating or earth ground chassis.
3. When testing any CRT that is installed in a chassis, first disconnect the chassis power plug from the ac line outlet. Do not apply power to the TV or monitor chassis at any time during the test of a CRT.
Download MANUAL Manual (PDF – 2.4 MB)
Bk-precision-480-490-instruction manual: 2.4 MB PDF for troubleshooting and calibrating Bk-precision models 480 and 490.
- Brand: Bk-precision-480-490-instruction
- Model: MANUAL
- Type: Manual
- File size: 2.4 MB
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
Bk-precision-480-490-instruction Overview
The Bk-precision-480-490 series is a versatile line of precision measurement instruments designed for accurate electrical testing and diagnostics. Ideal for both professional technicians and hobbyists, these devices offer reliable performance in a compact form factor. The series is widely used in laboratories, manufacturing, and field service applications to measure voltage, current, resistance, and other electrical parameters with high accuracy.
Main Features and Specifications
- Wide measurement range: DC/AC voltage up to 1000V, current up to 10A
- High accuracy with up to 0.05% basic DC voltage accuracy
- Multiple measurement functions including resistance, capacitance, frequency, and continuity
- Backlit LCD display for easy reading in low-light conditions
- Data hold and auto-ranging capabilities for convenience
- Robust build with overload protection and durable casing
- Compact and lightweight design for portability
Basic Usage and Operation Tips
Before using the device, ensure the test leads are properly connected and in good condition. Select the appropriate measurement mode using the rotary switch. For DC measurements, connect the test leads to the circuit and observe polarity. When measuring AC signals, ensure the device is set to AC mode. Use the data hold function to freeze readings for easier documentation. Always start with the highest range setting to prevent damage and then adjust downward for more precise readings.
Troubleshooting and Maintenance
If the device does not power on, check the battery and replace it if necessary. Ensure that the test leads are not damaged or loose. In case of inaccurate readings, recalibrate the instrument according to the manual instructions or consult a professional service center. Keep the device clean by wiping it with a soft, dry cloth and avoid exposure to moisture or extreme temperatures. Store the instrument in a protective case when not in use.
Safety Reminder
Always observe proper safety precautions when working with electrical equipment. Do not exceed the specified input limits to avoid electric shock or damage to the device. Use insulated test leads and wear appropriate personal protective equipment. Disconnect power before connecting or disconnecting the instrument to the circuit. Follow all local electrical safety regulations and guidelines to ensure safe operation.