General purpose isolated battery eliminator without door. Uses a high frequency converter and transformer to isolate power supplies and break ground loops. Typically used in bag systems to prevent ground loops when using a common battery supply. For matching doors with hole for power plug.

Battery Eliminator for UM & UH Series Transmitters • Allows external powering of Lectrosonics aluminum transmitters • Standard 9 volt battery contacts and DC input jack on “dummy battery” • Modified battery doors available for both BeltPack and Plug-On transmitters with flip-open style battery doors • Preserves use with regular alkaline or lithium batteries The ISO9VOLT battery eliminator allows Lectrosonics wireless transmitters with hinged battery doors designed for 9 volt batteries to be operated from external power sources. 10 to 18 volt DC is converted to regulated 9 volt DC to power the transmitter at the battery terminals inside the battery compartment. The modified door exposes the connector for the external power source yet still operates with regular dry cell batteries. The unit can supply up to 200 mA to work with the 250 mW transmitters. It is fused and protected from reverse polarity. The unique design isolates the power ground from the audio ground in the transmitter allowing the unit to be used in “bag systems” common in field production. When the mixer, receivers and wireless transmitters in a bag are powered by a common battery, a ground loop is often created which can cause high frequency noise (whining or hiss) in the audio. The external DC is run through a low drop out 12 volt regulator, then passed on to a DC/ DC converter that produces an 800kHz square wave. The square wave is passed through a transformer, rectified and then passed through a low dropout 9 volt regulator to produce the final DC power presented on the battery contacts. The battery eliminator has only been tested with Lectrosonics transmitter types shown here. Use with any other device will void the factory warranty. Lectrosonics will not accept responsibility for damage to nor ensure proper operation with any other devices. NOT FOR USE WITH TRANSMITTERS THAT HAVE ROTATING TYPE BATTERY DOORS. The ISO9VOLTH kit includes a modified battery door that fits any Lectrosonics UH type plug-on transmitters. The ISO9VOLTM model is a kit including the battery eliminator and a modified battery door that fits any Lectrosonics UM type belt-pack transmitter with a hinged type door as shown here.