RadioPopper PX - Manual (Page 5)

How It Works
The RadioPopper PX system is beautifully simple. Quickly mount the
PX Transmitter to your Master flash or Commander Unit, a PX Receiver
to each slave flash. Your current master and slave wireless flash system
continues to function just as it always has, minus the line of sight
limitation.
The RadioPopper PX Transmitter “listens” to the light signal being
created inside the master flash unit or remote commander on your
camera’s hot shoe. The PX Transmitter sends this signal by radio where
it is read by the RadioPopper PX Receiver. The receiver then uses it’s
own internal light source to “reproduce” this light signal. The light is
emitted through a window on the back of the Receiver unit directly
into the infrared sensor on a slave flash, that slave flash responds to the
“reproduced” light signal just as it normally would had it seen the light
directly from the master flash.
Installation is easy. Just place the RadioPopper PX Transmitter on top
of your master flash or IR commander device using the included Velcro
pads. “Look Ma! No wires!”
On the receiving end, assemble the mounting bracket for your specific
slave flash. Then simply drop the PX Receiver into the mounting
bracket. No wires or adaptors and no complicated system to re-learn.
Now just power up and shoot. You’ve got remote control of your slave
flashes, full ETTL and iTTL support along with high speed sync all the
way to 1/8000, by radio.
Introduction
Page 5