New structures of controllable attenuators

The new practical circuits of the electrical controllable diode attenuator have been developed. The characteristic feature of attenuators is very small phase shift at smooth regulation of the transfer factor. It is shown, that use of the correction circuits leads to essential reduction of the phase shift. For picosecond attenuators the phase stability of 1-5 degrees in working frequency band up to 2 GHz and attenuation range up to 25 dB is achieved.