The ETA-3A
ISA’s Premiere Telephone Analyzer

ETA-3A - Telephone Analyzer

The ETA-3A is specifically designed to test single line and electronic telephones, frequently used worldwide, in addition to fax machines. With an ETA-3A, the operator can test voltages both on and off hook, conduct multi-tone sweeping, listen to all wire combinations and check current flow in any combinations of wires. The ETA-3A displays voltages and currents on an easy-to-read digital panel meter.

The ETA Innovation

The ETA-3A is compatible with all types of electronic telephone systems and can safely test both digital and hybrid telephones. By use of an innovative multiple tone sweep generating system, the ETA-3A can simultaneously generate a main tone sweeping between 300Hz and 4,000 Hz in combination with a series of smaller range sweeping oscillators that overlap in their coverage. This technique assures the triggering of any multiple tone infinity transmitter that may be on the line.

High Voltage Testing

The high voltage test of the ETA-3A, is used to detect eavesdropping attacks utilizing Silicon Controlled Rectifiers (SCR’s), diodes, neon bulbs, etc. The voltage amplitude can be adjusted from the front panel and is monitored by the digital panel meter. When testing sensitive electronic systems, the ETA-3A will not produce any damaging voltages.


Power: Gel Cell Battery, 110/220 volt charger supplied
Size: 12” W x 10” D x 5”H
Weight: 12 lbs
Accessories: (2) 8 wire Extender Cable/ Clip Leads
Tone Generator