Use the antenna supplied with the transmitter, or any other Shure passive antenna that matches the RF operating range.
② LED Indicators
The LED indicators on the PA421B and PA421BX display RF signal and DC current draw. The LED indicators on the PA821B and PA821BX
display RF signal only. See the section on LED Indicators for more information.
③ Fan Vents
For system cooling.
④ Expansion Port
Connect an IEM transmitter or another combiner to share a single antenna. See the Using Multiple Antenna Combiners with a Single Antenna
section for connection information.
⑤ Power LED
Green: Combiner is powered on.
Red: Indicates fan fault
Green/red flashing: Maximum temperature has been exceeded
Warning! If maximum temperature has been exceeded, attention is required. Allow the combiner to cool. If condition persists, send the unit to Shure Service and Repair.
⑥ Power Switch
Rear Panels
PA421B
PA821B
① Power Input
Connects unit to AC power.
② Exhaust Air Vents
For system cooling.
③ DC Power Outputs
Available on the PA421B and PA421BX models for powering compatible transmitters.