CMA-100 Countermeasures Amplifier

Research Electronics International, LLC (REI) is one of the world’s leading manufacturers of Electronic Detection and Testing Equipment for Security Applications.

Based in Cookeville, Tennessee, USA, REI specializes in Radio Frequency (RF) Detectors, Non-Linear Junction Detectors (NLJDs,) Telephone & Line Inspection Equipment, Audio Security Equipment (including Acoustic Noise Generators,) Video Inspection and Physical Inspection Equipment to locate Electronic Bugs or Eavesdropping Devices.

CSSPakistan in proud association with REI LLC brings you CMA-100 Countermeasures Amplifier.

High Gain Audio Amplifier

CMA-100 Countermeasures Amplifier is a high gain audio amplifier used to detect and identify certain types of surveillance devices attached to building wiring such as telephone wiring, LAN and server systems, AC power, and alarm wire. The CMA-100 Countermeasures Amplifier functions employ a sophisticated automatic gain control circuit that is superior to most audio amplifiers.

Efficiency: large signals can be monitored with minimal distortions and adjustable bias voltage can activate devices that are voltage or current sensitive

Usability: balanced input impedance can withstand being attached to live power lines with voltages up to 250V

Portability: contains a built-in AC/DC digital voltmeter, select-able audio filters, and a wide dynamic range

CMA-100 Countermeasures Amplifier Pics

Technical Specifications

1. Features

  • Balanced input impedance of 50K ohm, can withstand being attached to live power lines with voltages up to 250V, and provides up to 115dB of gain
  • Unique AGC that has 105 dB of control
  • Signals as large as 31V peak-peak can still be monitored with minimal distortions
  • Manual gain control can be set to 0, 25, 50, 75, or 100 dB
  • Filters can be positioned to FLAT, LOW PASS, HIGH PASS, or BAND PASS.

2. Applications

  • Technical Surveillance Countermeasures (TSCM)
  • Counter Surveillance
  • Audio Amplification
  • Wiring Testing
  • Eavesdropping Detection
  • Intelligence Protection
  • Executive Protection
  • Surveillance Equipment Detection
  • Electronic Surveillance Detection

3. Specifications


50k Ω balanced
Common mode rejection: >75dB
Maximum usable input: 31 Vp-p
Preamp auto attenuator: 0 to -40 dB (with overload warning LED)


0 to +/-14.5V DC, 5mA max (over current protected, input impedance is reduced to 3.6k ohms when bias is active)


250V AC/DC
Leakage resistance to case: >10M Ω


Manual gain control: 0, 25, 50, 75, 100 dB
Headphone gain control: 0 – 15 dB
Maximum system gain: 115 dB Manual mode, 120 dB in Auto mode


3.5 Digit, auto zero, auto polarity, +/-199.9V AC/DC


No filtering: 25 Hz – 44Khz
High pass filter: 320Hz – 44kHz
Low pass filter: 25Hz – 3.2kHz
Band pass filter: 320Hz – 3.2kHz


Headphone audio output
Line-out audio output: 600 Ω


Power on/low battery LED (LED off @ 6.0V)
Battery: 9V Alkaline (5 – 30 hours typical run time)


Unit dimensions: 7.3 in x 2.75 in x 1.75 in (185.4 mm x 69.8 mm x 44.5 mm)
Unit weight: 12.1 oz (343 g)

5. Included Accessories

There are currently no accessories associated with this product.

CMA-100 Countermeasures Amplifier is One of The World’s Most Advanced Audio Amplifiers which Detects and Identifies Surveillance Devices attached to Building wiring such as Telephone Wiring, LAN and Server Systems, AC power, and Alarm Wire.

An Indispensable Tool to Secure Your Premesis.

Call Capital Services System now at +92 51 2110 525 or send us an email at: to know more about CMA-100 Countermeasures Amplifier.

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