TekBox Modulated Wideband Driver Amplifier (TBMDA3)


The TBMDA3 modulated wideband power amplifier is designed in order to create an inexpensive signal source for immunity testing of electronic building blocks and products. It is designed to be driven by the tracking generator output of spectrum analyzers. With an input power range of -5dBm…0dBm, it can boost the output power of a tracking generator up to 5W.

The TBMDA3 is ideal to drive Tekbox near field probes in order to find the sensitive spot of an electronic circuit or to create electric fields up to 550V/m when driving the Tekbox TEM Cell TBTC0, 300V/m when driving the TBTC1, 150V/m when driving the TBTC2 or 100V/m when driving the TBTC3. Test signals for immunity testing can be CW, AM or PM modulated. Consequently, the TBMDA3 provides built in modulation capability to generate 1 kHz AM or PM signals. In PM mode, the TBMDA3 can also generate a 217 Hz Signal with 12.5% duty cycle in order to simulate mobile phone TDMA noise.


  • CW amplifier (modulation off)
  • 1 kHz, 80% AM modulation
  • 1 kHz, 50% duty cycle pulse modulation
  • 217 Hz, 12.5% duty cycle pulse modulation


Input / Output: 50 Ohm, N female
Supply Voltage range: 110 V…240 V
Supply power consumption: 20 W
Maximum input power: +3 dBm
Operating temperature range: -20°C to 50°C
Frequency range: 10 MHz – 1 GHz
1dB output compression point @ 10MHz: +36 dBm typ
1dB output compression point @ 100 MHz: +37 dBm typ
1dB output compression point @ 500 MHz: +36 dBm typ
1dB output compression point @ 1 GHz: +34 dBm typ
Harmonics: < – 10 dBc typ.
Internal modulation frequency AM: 1 kHz ±10%
Internal modulation frequencies PM: 1 kHz ±10%, 217 Hz ±20%
Duty cycle, PM: 50% ±10% @ 1 kHz; 12.5% ±20% @ 217 Hz


3 MHz7 MHz25 MHz100 MHz200 MHz300 MHz400 MHz500 MHz
22.5 dB39.6 dB42.7 dB44.7 dB44.4 dB43.7 dB42.6 dB42.3 dB


600 MHz700 MHz800 MHz900 MHz1 GHz1.1 GHz1.2 GHz
39.6 dB40.1 dB39.3 dB38.5 dB37.3 dB36.8 dB35.9 dB


  • General-purpose gain block
  • Signal source for immunity testing, driving near field probes
  • Signal source for immunity testing, driving TEM Cells

TBMDA3 Manual

Weight3.7 kg
Dimensions35 × 31 × 22 cm