I. Introduction
In today's scenario, it is observed that various types of RF subsystems required for various Radar and EW applications are becoming more compact, lightweight, and multifunctional and hence getting more complex. These RF subsystems are typically receivers, transmitters and various other microwave super-components. Earlier two layer design was used with RF circuit on one side and Power supply & control on other side. But the need for compact, multichannel, multifunctional and wideband applications has resulted in two or more RF layer design and hence introducing the problem of multiple RF cross-overs. DC or very low frequency cross overs can be easily solved by using wire jumpers. But same thing cannot be used for RF cross overs. So, a simple & cost-effective RF cross-overs over wide frequency band needs to be realized for two or more RF layer design. Here, impedance matching over wide RF frequency range at transitions [1] is the most critical for good RF cross-over design. To achieve this, various solutions are available [2] [3]. Here, it is proposed a simple, cost-effective, flexible solution for RF cross-overs using vertical coaxial transition with respect to microstrip consisting of Teflon Bush (PTFE) along with Launch Pin (Beryllium Copper). It can be customized to any length and diameter depending on RF PCB board to board distance.