Abstract: An isolator/circulator circuit for use in any kind of electronic system wherein reflected signal insertion loss is eliminated or minimized while bandwidth of the system is generally unlimited and limited only by the bandwidth of the amplifiers PA1 and PA2 and by the bandwidth of the divider/combiner X2 and X4, one (1) octave as minimum and several as maximum. The circuit allows this technique to be used in low frequency applications below MHz range where circulator/isolator sizes/cost become prohibitive and physically impossible to fabricate.

Abstract: A RF input signal system and method switches the RF input signal amplified by an amplifier PA1 or PA2 to be present only in great magnitude at the summing port of a hybrid combiner H2 when the SPDT switch SW1 is directing the “RF in” signal to the summing port of the hybrid divider H1, while the balancing port of H1 is terminated by the switch SW1. The benefit of switching between H and V ports by using this method eliminates the insertion losses of the switch SW1 and isolators ISO1 and ISO2 of the prior art. The benefit is also the speed of switching which can now be executed much faster (in nanoseconds) in comparison to the method shown in FIG. 1 where the limiting factor are the PIN diodes used in such devices (SW1 of FIG. 1) that only allows switching transients in tens of microseconds only. The non-summing port of H2 is then only radiating much less energy of ?20 to ?30 dB below that of the summing port.