Compare Preamplifier, 1 to 1000 MHz, 33 dB gain
The PAM-103 is a broadband, high gain, low-noise preamplifier operating over the frequency range of 1 MHz to 1 GHz. Its high gain (33 dB ±3 dB) and low noise figure (<3.3 dB) make the PAM-103 Preamplifier the ideal choice for optimizing your EMI measurement system, whether it be for an absorber lined test chamber, open area test site or tem-cell.
The PAM-103 can be powered by its internal, rechargeable battery packs, or by its AC to DC Power Adapter/Battery Charger. On a full charge, the preamp will operate on battery power for over 13 hours. The battery low indicator light will let you know when it is time to plug it in; and the charging indicator light will let you know that its charging. If you are unable to plug it in, you can feel confident in continuing your test, as the PAM-103 will turn itself off well before the battery voltage reaches the point at which the gain could become unstable. Whether it’s operating on battery power or external power; if the amp is on, you can rest assured that the output is stable and that the gain will remain constant.
Construction
The durable enclosure for the PAM-103 is designed to withstand years of punishment in any laboratory environment. It is constructed from rugged, high-quality aluminum, with an external powder coat.
The RF input and output ports are each fitted with an N-type (female) connector. The battery packs, should they need to be replaced, can be accessed via the removeable panel on the underside of the enclosure.
Why is a Pre-amplifier Needed?
Nearly all measurement systems for radiated EMI tests require preamplification in order to achieve the necessary sensitivity. The sensitivity is determined by system noise floor level, which usually appears as a thick ‘fuzz’ across its frequency range. The upper extreme of the ‘fuzz’ represents the bottom end of the instrument’s dynamic range (for the respective instrument bandwidth setting) throughout its frequency range. The noise floor level increases/decreases proportionately (10 dB per decade of bandwidth change Signals below the noise floor level are essentially masked (hidden). In addition, signals with amplitudes near the level of the noise floor typically measure higher than actual. Therefore, for the best measurement accuracy, the noise floor should be as far below the spec limit as is possible.
The graphs represent typical measurement system noise floor levels with and without the PAM-103 preamplifier. The noise levels are shown in relation to the CISPR 22, Class A/B limits. As you can see, the noise levels on the upper plot (without preamp) actually exceed the Class B limits. Typical errors using this measurement system would likely include false failures (<450 MHz), and non-detection of EUT emissions in excess of the limit (>450 MHz). As shown on the lower plot (with preamp), the noise floor is well below both limits.
Calibration
Each preamplifier is individually calibrated with NIST traceability. The calibration data and certificate is provided. ISO/IEC 17025 accredited calibration is available upon request.