Product Details


Note: PA421A has been discontinued. The replacement product is PA421B.

Shure PA421A Antenna Combiners are complementary accessories for Shure PSM Personal Monitor systems.

When multiple systems are required for monitoring environments, the PA421A combiners quietly and efficiently optimize RF management for up to four PSM transmitters when racked in a central location, while also reducing rack clutter.

PA421A combiners ship with UA802 Coaxial Cable.

PA421A combiners replace PA421SWB Antenna Combiners.



  • Combines up to four PSM transmitters to a single antenna set
    • Improved RF networking
    • Reduce rack clutter
  • Quieter fan for significant reductions in ambient unit noise
  • Temperature-sensitive fan power for significant reductions in ambient unit heat
  • 4 Input LED Signals (green when active; off when inactive)
  • 4 DC Power LED Signals (green when active; off when inactive; red when active but interrupted/shorted)
  • Active-channel amplifier power for additional reductions in ambient unit heat
    • 1 Channel engaged = 1 power amplifier active
    • Updated from PA421SWB, in which all power amplifiers were active in a block, regardless of how many of the 4 channels were active
  • Passive (non-powered) antenna combining (Contact Shure Service Department for more detail and availability)

Software & Downloads

User Guides

File Language Type File Size
PA421A User Guide

Product Support

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