Lectrosonics UM250b - Manual (Page 3)

UHF Belt-Pack Transmitter
INTRODUCTION
Thank you for selecting the Lectrosonics UM250B frequency agile, belt-pack transmit­
ter. The UM250B combines over 80 years of engineering experience with the very
latest components, in a design that addresses the most demanding professional
applications.
The design of the UM250B was the direct result of numerous conversations with
users, staging and touring companies and dealers across the US. The specific
concerns and needs brought up in these conversations led directly to the develop­
ment of the operational features offered on the UM250B. Two hundred fifty six
frequencies are user selectable in 100kHz steps to alleviate interference problems in
travelling venues, and the low frequency roll-off is user adjustable to adapt to varying
acoustic environments and preferences.
The UM250B is a rugged, machined aluminum package with a removable, spring
loaded belt clip. The input section provides a correct input tap for virtually any
microphone or line level audio source. 5 Volts of bias voltage is available to power
electret mics with either positive or negative bias. Level indicating LEDs are pro­
vided on the control panel to make level settings quick and accurate, without having
to view the receiver. The battery compartment accepts any 9 Volt lithium or alkaline
battery and makes a positive connection via self-adjusting contacts. The antenna is
a detachable, locking 1/4 wavelength flexible bronze cable that connects to a 50
Ohm SMA port on the transmitter.
Only the UM250B transmitter is covered in this manual. Companion receivers are
covered in separate manuals. The UM250B will operate with any 200 Series Lec­
trosonics receiver in the same frequency group.
Rio Rancho, NM – USA 3