The EV1050 Evaluation Kit comprises a single board containing an FX105A. Switches select variable resistors for adjusting the detect frequency, bandwidth and response time. Many of the fixed components are socketed so that they can be changed by the user. The EV1050 board is powered from a single 8 - 35V external dc power supply; an on-board regulator sets 3.0V or 5.0V operation. An LED indicates the status of the detect output. The supply current of the FX105A may be measured by removing the appropriate jumper. Test points are provided for the signal input, the VCO output and the detect output. A user prototyping area is provided.