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180-degree IF hybrids are potentially useful for balanced superconductor-insulator-superconductor (SIS) mixers. We have developed a compact Nb-based 180-degree hybrid for 4-12 GHz which addresses concerns of element size, ohmic loss, and IF bandwidth. The fabrication scheme developed for these elements will be discussed, including the use of a thin overlayer Au process for via contacts, RF diode sputtered SiOx in lieu of sublimated SiO films in order to improve the wafer yield, and diagnostic Nb capacitors to evaluate these SiOx films. Experimental results will be presented and compared with simulations of these lumped element transmission line ‘rat-race’ hybrids. It should be noted that the hybrids can be used in cryogenic balanced mixers for any RF band. [ABSTRACT FROM AUTHOR]