Interface Gauges



Testing the interfaces of connectors and adapters upon incoming inspection is not only highly recommended, it is definitely a necessity. Interfaces not meeting specification will not only lead to degraded specification of the components, furthermore, these out of specification interfaces may damage the connectors of mating components or ruin the connectors of test equipment.



Spectrum Elektrotechnik GmbH manufactures a comprehensive line of connector gauges for measuring the critical interface dimensions of coaxial connectors. These connector gauges consist of an especially adapted dial indicator with appropriate bushings and pins that are designed to mate with the specific connector under test. The indicator of each gauge is zero set by a specific master gauge. When engaged to a connector, it measures the specific interface dimension from a specific reference plane. For every dimension of interest, a special gauge will be offered. This gives the most accurate results, allows easy calibration, fast testing and helps to avoid mistakes.



A number of gauges are available. The main difference between these four types of gauges is the different resolution as well as the units of measurement: inches or metric. Only the digital gauges can be switched from metric to inch and vice versa.

Interface Gauge - Type H


This gauge is available with
a resolution of
0.005 mm or 0.0001 inches.
Interface Gauge - Type K


This gauge is available with
a resolution of
0.01 mm or 0.001 inches.
Interface Gauge - Type D


This gauge employs a digital readout
and can be switched from a resolution of 0.01 mm to 0.0005 inches.
Interface Gauge - Type T


This gauge uses
a resolution of 0.001 mm
and is available in metric only.



Most Gauges shown are available as “Hand-Held” or “Thread-On”. The faster testing is possible by using the “Hand-Held” gauges, the more accurate readings will be achieved from the “Thread-On” gauges, as threading on the gauges will perfectly align them with the connector. Hand-Held means aligning gauge and connector freely, which may allow for mistakes.



Complete interface dimensions of the connectors are shown here. The important measurements are marked clearly for every connector series:

Dimensions, highlighted in an oval shape, are recommended for verification as a minimum. The connector gauges measuring these dimensions are included in the Expanded Calibration Kit and the Professional Kit as well.


Dimensions, highlighted in a rectangular shape are recommended for verification in addition to the dimensions highlighted in an oval shape. Checking all these dimensions will guarantee optimum performance of the connectors. The necessary connector gauges to measure all those dimensions are included in the Professional Calibration Kit only.



Select the correct gauge for the connector under test. Inspect the gauge and the appropriate calibration block (master) and make sure that both are in good condition and clean. (Dirt on the gauge or the master will lead to inaccurate measurements and can transfer dirt to the connectors and damage them during gauging). Attach the calibration block carefully to the gauge. Zero the gauge by moving the dial until the gauge pointer reads zero. To verify that the setting is correct and repeatable, remove the calibration block and then attach it a second time.
When testing the connectors, make sure that they are not damaged and clean. When using the “Thread-On” gauges, tighten the connection with the appropriate Torque Wrench only.

Interface Gauges
Contact Details
Spectrum Elektrotechnik GmbH
Olschewskibogen 1
80935 Munich

Mailing address:
P.O. Box 450 533
80905 Munich

+49 (0)89 / 354 804-0
+49 (0)89 / 354 804-90