130

The Tektronix Type 130 is a self-contained instrument, designed by Cliff Moulton and introduced in 1959, that measures inductance and capacitance.

There are at least two versions of Type 130. Early units (SN 101-5000) have a narrow boxy case that slides off the chassis, backlit meter, and are marked "TYPE 130 L,C METER". At some point between SN 101 and SN 842, the case color changed from brown to blue. Later units (SN 5001-Up) have a wider, rounded case with side panels that pop off, blue paint, non-backlit meter, and are marked "TYPE 130 L-C METER".

Key Specifications

Ranges	3, 10, 30, 100 or 300 pF / 3, 10, 30, 100 or 300 μH full scale
Accuracy	3% FS, 1% FS with "careful" calibration using S-30 Delta Standard
Measurement voltage	<1 V for capacitors, <0.25 V for inductors, 120-140 kHz
Guard output	250 Ω source impedance, can drive 200 pF
DUT connection	UHF connector (DUT) + 4 mm jack (guard)

Manuals

Tektronix 130 Manual 070-231 (PDF) / 070-231 Manual Restored by Alan Hampel (PDF @ vintagetek.org, includes redrawn schematics)
Tektronix 130 Manual 070-231-01 (PDF, covers both cabinet types)
Tektronix 130 Factory Calibration Procedure (PDF)

Links

Q+A: Type 130 L-C Meter and S-30 Delta Standards. Service Scope No. 18, Feb 1963.
Silicon Chip, June 2020 - Vintage Workbench - Tektronix T-130 LC Meter: Part 1 / Part 2 / Part 3 (PDFs @ vintagetek.org)

Internals

The 130 contains an LC oscillator with a tank circuit formed by the device under test and a capacitor or inductor internal to the 130. The oscillator's frequency is measured by mixing it down using a fixed reference frequency, generating a pulse at each zero-crossing, and integrating (low-pass filtering) the pulse train. This produces a voltage that is proportional to the frequency difference between the LC oscillator and the reference oscillator. This voltage is displayed on a d'Arsonval (moving coil) meter on the front panel of the 130.