Midian Electronics' IS-1 is an interoperability switch or a cross-band repeater maker for allowing 2 radio systems on different channels or different bands to communicate with one another. For example a UHF radio system and an HF SSB radio system can interoperate or a VHF radio system can interoperate with a UHF P25 radio system.
When the IS-1 sees COR or VOX from radio system 1, the IS-1 will give a PTT output to radio system 2 and pass the audio from radio 1 to radio 2. The IS-1 can be powered by a 9 Volt battery for more than 40 hours, or can get the power from an external source such as a mobile radio or from an optional wall power adaptor. A monitor output is available for monitoring the radio traffic or outputting to a voice recorder.