Test set T-111; manufactured by Zellweger AG, Uster.

With the T-111, Zellweger, Uster, developed a multifunctional modular test set in the late sixties. This provided the Uem Ger Mech (Signal mechanic) with the necessary tools for diagnosing, repairing and calibrating radio equipment, even in an improvised workshop environment.

The T-111 test set, which combines a tube voltmeter, an R.F. generator, an A.F. / tone generator and a small oscilloscope in one cabinet, also is of excellent value in many a hobby room; the signalling test set for checking ETK and STG-100 (teleprinter CCiTT No.2) is probably not used so often.\

• Principle: Modular test set
• Operation modes
  • Voltage & resistance measurements
  • A.F. generator, frequency range: 20 Hz - 20 kHz
  • R.F. generator, frequency range: 165 kHz - 56 MHz
  • Oscilloscope, 0 - 2 MHz
  • Impulse generator for ETK / STG

• Mains operation: 220 V AC mains supply

• 453 x 380 x 310 mm; 35 kg

• Test cables and probes are located in the accessories compartment in the lid

The T-111 test set is primarily designed for working on military high power radio stations and is built into a metal case similar to the accessory box for the SE-222 / SE-415. With its dimensions of 45.3 x 38 x 31 cm, it has a weight of 35 kg.

The T-111 consists of five components:

• A cathode ray oscilloscope (CRT) with a frequency range of 0 - 2 MHz to display all types of signals on its small screen.
• A tube voltmeter / electronic voltmeter to measure voltages up to 300 V DC and 600 V AC; voltages up to 3000 V can be measured with a high-voltage probe. It can also be used as an ohmmeter.
• A RF generator provides R.F. signals from 165 kHz to 56 MHz, stable reference signals of 1 and 10 MHz are also provided.
• The AF / tone generator generates audio signals from 20 Hz to 20 kHz.
• A impulse generator can provide all characters of the ETK and also the STG-100 with different pulse sequences for test purposes.

For operation, the chassis carrying the measurement instruments must be slightly pulled out of the transport case after pushing in and turning two big metal knobs on both sids; better air circulation prevents the set from overheating during operation.

The cables and measuring probes required for the various measurements are stored in a compartment under the hinged cover on the top of the set.

At the request of the KTA to develop a universal test and measuring set, Zellweger developed the T-111 test set in 1967/68 to carry out the most important repair and maintenance work on the SE-222 and SE-415 radio stations and the associated teleprinters.

The 110 test set which were acquired and delivered to the troops in 1970/72 and were used by the Uem Ger Mech (signal mechanics) until the previous high power stations were replaced by the SE-430 with its multiple self-test functions and modular design (in which repairs were replaced by replacing defective modules).

T-111

T-111

T-111

• T-111: Test and measuring device T-111, Volume 1, Description and operating instructions
• T-111: Test and Measuring Device T-111, Volume 2, Technical Manual and Revision Instructions

• T-111 at www.armyradio.ch
• T-111 on the website of www.radiomuseum.org