The manual for the Sencore Mighty Mite tube checkers provides detailed instructions for setting up and operating models TC114, TC130, TC136, TC142, and TC154, including how to test tubes for shorts, emission, and grid leakage. It also includes troubleshooting tips, such as performing a life test to identify filament-sensitive cathodes and checking magnoval-based tubes without damaging the socket.
Manual Overview
The Sencore Mighty Mite tube checker models TC114, TC130, TC136, TC142, and TC154 are designed for testing over 3,000 types of tubes. For setup, controls A, B, C, and D should be adjusted according to the set-up chart, and the tube should be inserted into the indicated socket. Calibration is achieved by setting the FUNCTION switch to CAL and adjusting the CAL control for full scale on the meter. For the TC154, the SHORTS function is used to adjust the METER ZERO control. The SHORT TEST checks for shorts or excessive leakage by rotating the D switch; any unexpected shorts should lead to immediate tube rejection to prevent damage. The EMISSION test involves switching to the EMISSION position and reading the meter scale to determine tube viability. A LIFE TEST is recommended to identify filament-sensitive cathodes by reducing the filament voltage and observing meter changes. GRID LEAKAGE is checked by reading the bottom scale. Special care is needed for magnoval based tubes to avoid socket damage. This comprehensive testing ensures reliable tube performance and prevents potential issues in electronic circuits.
Quick Issues Covered
- Diagnose tube shorts using the SHORT TEST function.
- Adjust CAL control for accurate meter calibration on TC142.
- Use schematics for circuit tracing and troubleshooting.
Overview
The product is a series of tube checkers known as the Mighty Mite models TC114, TC130, TC136, TC142, and TC154, manufactured by Sencore. These devices are designed to test over 3,000 tubes for emission at full rated cathode current, grid leakage, and shorts. The manual provides operating instructions, including setting controls according to a set-up chart, performing shorts and emission tests, and conducting a life test for filament-sensitive cathodes. It also includes specific instructions for handling magnoval based tubes and emphasizes the importance of checking certain tubes in television receivers to prevent damage and ensure proper function.
Specifications
- Checks over 3,000 tubes
- Checks emission at full rated cathode current
- 100 megohms grid leakage test
- Stethoscopic shorts test
- Portable, rugged all steel case
Controls & Indicators
Refer to the PDF for details.
Installation / Setup
Refer to the PDF for details.
Operation
Set controls A, B, C, and D according to the set-up chart and insert the tube in the socket indicated. Use the cap lead if the tube has a top cap connection. For Mighty Mites up to TC142, set the FUNCTION switch to CAL and adjust the CAL control for a full-scale meter reading. For the TC154, press the SHORTS function pushbutton and adjust the METER ZERO control to position the meter pointer to the extreme left of the scale.
Switch to the SHORT TEST or SHORTS function and rotate the D switch through all positions. The SHORT IND. or SHORTS light will glow if a tube is shorted or has excessive leakage. Tubes marked with an asterisk in the set-up chart have internal connections that will show up as a short on certain D switch positions. The H-K setting is for heater to cathode leakage or short test. Reject any tube showing a short not indicated as normal to avoid damage to the Mighty Mite transformer.
Switch to the EMISSION position and return the D switch to the setting indicated in the set-up book. Read the top BAD ? GOOD scale on the meter, and reject any tube that reads in the BAD area.
For tubes with a FILAMENT SENSITIVE cathode, perform a LIFE TEST by switching the FILAMENT (A) switch down one step after testing for emission. A good tube will not change or will change only slightly, but a filament sensitive tube will drop quickly to the BAD area. Replace any tube that drops to the BAD area.
Switch to the GRID LEAKAGE function and read the bottom GOOD ? BAD meter scale. Reject any tube that reads in the BAD area.
When replacing a costly horizontal output tube in a television receiver, check the horizontal oscillator tube for emission, filament sensitive cathode, and warm-up time. Ensure the oscillator tube warms up as fast or faster than the output tube to avoid shortening the output tube’s life.
For magnoval based tubes, check them in socket number 12 on the Mighty Mite V and in socket number 5 on the Mighty Mite II, III, and IV. Do not insert the tube fully into the socket to avoid damage. Hold the tube for firm contact during the test.
Troubleshooting & Error Codes
Refer to the PDF for details.
Safety & Warnings
The manual contains the following safety warnings and precautions:
1. Any tube that shows a short not indicated as normal should be rejected immediately to prevent possible damage to the Mighty Mite transformer from checking a shorted tube for emission.
2. When checking magnoval based tubes, do not insert the tube fully into the socket to avoid spreading the contacts and causing damage. Instead, hold the tube while making firm contact between the tube pins and socket contacts for the test.
Download 2 Manual (PDF – 4.5 MB)
Sencore TC142 Mighty Mite Model 2 manual assists technicians in setting up and referencing tube charts for efficient troubleshooting.
- Brand: Sencore-tc142-mighty-mite-set-up-book-tube-chart
- Model: 2
- Type: Manual
- File size: 4.5 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
Sencore TC142 Mighty Mite Set-Up Book Tube Chart – Overview
The Sencore TC142 Mighty Mite is a specialized electronic test instrument designed primarily for servicing and testing vacuum tubes in vintage radios, amplifiers, and other tube-based equipment. This compact and portable device provides technicians and hobbyists with essential data and setup information to accurately measure tube parameters, ensuring optimal performance and reliable operation of tube circuits.
Main Features and Specifications
- Comprehensive tube chart covering a wide range of vacuum tube types
- Compact, lightweight design for easy portability
- Accurate tube testing parameters for quick diagnostics
- Clear and easy-to-read setup instructions included
- Durable construction suitable for workshop environments
- Compatible with various Sencore Mighty Mite tube testers
Basic Usage and Operation Tips
To use the TC142 tube chart effectively, first identify the tube type in your equipment. Refer to the chart to find the correct setup information, including pin connections and test settings. Always ensure the tube tester is powered off before inserting or removing tubes. Use the chart as a guide to adjust the tester controls for accurate measurement of tube parameters such as emission, mutual conductance, and shorts. Regularly consult the manual to familiarize yourself with the specific test procedures for different tube types.
Troubleshooting and Maintenance Notes
If you encounter inconsistent or inaccurate readings, verify that the tube is properly seated and that the tester’s contacts are clean and free of corrosion. Periodically clean the socket contacts with appropriate electronic cleaner to maintain reliable connections. If the device fails to power on or shows erratic behavior, check the power supply and fuse. Refer to the manual for detailed troubleshooting steps and contact Sencore support for advanced repairs.
Safety Reminder
Always handle vacuum tubes and electronic equipment with care. Ensure the tester is disconnected from power before servicing or changing tubes to avoid electric shock. Avoid touching hot tubes immediately after testing, as they can cause burns. Follow all safety guidelines outlined in the manual to protect yourself and your equipment.