Heathkit IM-5228 User Manual

Details DC voltage measurement ranges, input resistance, circuit type, and accuracy.

Details AC voltage measurement ranges, frequency response, circuit type, and accuracy.

Details ohmmeter ranges, meter type, probe details, tubes, and battery specifications.

Explains the VTVM's intended use for servicemen, engineers, and maintenance personnel.

Discusses the VTVM's high input impedance and its advantage over VOMs for loading effects.

Refers users to the 'Kit Builders Guide' for detailed assembly and wiring instructions.

Explains how DC and AC voltages are processed through the circuit for measurement.

Describes the ohmmeter function, utilizing a battery and resistor network for measurement.

Explains the bridge circuit and how the meter movement indicates readings based on cathode potential.

Lists various resistors and capacitors with their part numbers, values, and descriptions.

Lists potentiometers, controls, and switches used in the VTVM assembly.

Lists vacuum tubes, neon lamp, diodes, terminal strips, jacks, and plugs.

Lists parts for the test probe, wire, and sleeving used in the instrument.

Lists cabinet, chassis, front panel, hardware, and miscellaneous items.

Presents a basic battery eliminator circuit using an LM317 adjustable voltage regulator.

Shows a battery eliminator circuit with added protection diodes for enhanced stability.

Advises inspecting wiring, components, and removing debris before powering on the unit.

Instructs to turn on, check pilot lamp, and observe initial meter behavior during warm-up.

Guides on checking the ZERO ADJ control for stable zero across DC modes.

Details preparing the probe insert insulator and assembling the 1 megohm resistor with rivets.

Instructs on soldering resistor leads to rivets and probe tips for the test probe assembly.

Details adjusting the mechanical zero position of the meter pointer using a screwdriver.

Instructs on calibrating the DC measurement scale using a flashlight battery.

Guides on checking the ohmmeter function and setting infinity on the scale.

Provides steps for AC calibration using an adapter for 2-wire outlets.

Provides steps for AC calibration for 3-wire outlets without an adapter.

Details securing the instrument in the cabinet using sheet metal screws.

Explains mounting the gimbal bracket and selecting desired VTVM positions.

Guides on installing the plastic feet onto the gimbal bracket for stability.

Discusses the benefits of leaving the VTVM on continuously during daily work.

Outlines essential safety rules for operating the VTVM, especially with high voltages.

Explains how to use the combined AC-OHMS-DC test probe for convenience.

Explains how to read voltage scales for different ranges by adjusting decimal points.

Explains how to read resistance scales and apply multipliers for RX1, RX10, etc.

Details connecting common lead, setting OHMS function, and adjusting OHMS ADJ control.

Advises against leaving the VTVM in OHMS position to preserve battery life.

Details DC accuracy (2% meter, 1% multipliers) and AC accuracy (5%).

Lists factors affecting ohmmeter accuracy, including battery voltage and internal resistance.

Recommends checking wiring, connections, and soldering quality for proper function.

Advises checking tube illumination, substitution, and verifying component values.

Offers tips like checking debris, foreign matter, and comparing voltage readings.

Lists causes for completely inoperative, DC balance, AC inoperative, and AC balance problems.

Covers potential causes for inaccurate AC readings and calibration issues.

Lists causes for inaccurate DC readings and inoperative/inaccurate ohmmeter functions.

Advises against repairing the delicate meter movement to maintain warranty coverage.

Explains how to correct static charge buildup on the meter cover using detergent.

Details checking meter coil continuity safely and potential test lead issues.

Describes an optional probe for high voltage measurements up to 30,000 volts.

Describes an optional probe for RF measurements up to 30 volts.