Sennheiser SKP500G4 Wireless Plugpack Transmitter with 48v phantom
The plug-on transmitter features switchable 48V phantom power, 3520 frequencies that are tunable in 25 MHz steps, 20 fixed frequency banks, 32 compatible frequency presets, and 6 user banks with up to 32 user programmable frequencies. The transmitter's menu-driven backlit display shows the current frequency, frequency bank and channel number, metering of AF level, lock status, transmission status, muting function, battery status, and more.
In addition, the plug-on transmitter incorporates a Sennheiser HDX compander system, a defeatable pilot tone squelch, and is equipped with a frequency range from 80 Hz to 18 kHz. Finally, power is supplied to the transmitter by the two included 1.5V AA sized batteries, or by one optional Sennheiser BA 2015 rechargeable accupack. A pouch with a belt clip is included. The item is also compatible with the Auray UPOH-B Universal Plug-On Transmitter Holster.

