Abstract: A frequency plan for a signal analysis circuit includes operational parameters that are selected on the basis of first intermediate frequency (IF) filtering characteristics that are uniquely identified for the circuit. That is, rather than selecting a frequency plan based upon an original design of the circuit and circuit layout, actual IF filtering characteristics are considered. The center frequency of the passband of the first. IF filter may be measured and then used as an important factor, along with inhibiting spurious responses, in a devising the frequency plan for the specific circuit.

Abstract: A hybrid printed circuit board comprising two substrates having different thermal coefficients of expansion can be manufactured using automated surface mount techniques. A daughterboard is configured with a number of contact pads on the bottom. A motherboard is configured with an aligned set of contact pads on the top with solder compound stenciled on them. The daughterboard is attached to the motherboard using standard automated surface mount techniques.

Abstract: A wideband bandpass filter has a tank circuit connected between an input and output tapping circuit. The tank circuit contains a variable capacitor and an inductor in parallel. The tank circuit determines a center frequency for the bandpass filter. The input tapping circuit has an input variable impedance, and the output tapping circuit has an output variable impedance. The input and output variable impedances determine the continuously variable bandwidth of the filter.