RB02, Rocket Beeper 4
Note the polarity of the battery connector (J1
on the circuit board). Lithium batteries with
JST PH2 connectors do not all have the
positive and negative in the same place.
Check your battery to be sure the positive
(red) and negative (black) are on the correct
sides. The connectors in the battery’s JST
plastic shell can be removed and reversed by
prying up the plastic retaining latches with
the tip of a sharp knife - like an X-Acto
knife. Note your battery charger will also
need to have matching polarities - the
charger will be damaged if the connected
battery is reversed.
To keep the battery from getting scratched by the wires on the bottom of the RB02 circuit board
you may want to glue a piece of cardboard on one side of the battery as shown in the picture on the
left. This picture also shows the correct location of the red and black wires in the JST PH2
connector.
Using the RB02
Attaching the RB02. The RB02 can be attached to your rocket via the “suspension” hole in the
circuit board. A flexible cord (such as kevlar string) passed through this hole will keep the RB02's
beeper pointed at the ground during recovery.
Securing the battery. The battery can be held against the bottom of the RB02 circuit board by a
rubber band wrapped around the circuit board. Both ends of a short rubber band go in slots on the
side of the circuit board, see Figure 2. The battery can be more securely attached with the
following methods. In addition to the rubber band, use double-sided foam tape on the bottom of
the circuit board to hold the battery in place. In addition to double-sided foam tape, use a short
piece of large diameter transparent heat-shrink over the RB02 circuit board and battery. Shrink it
to secure the battery in place then cut an access to the ON/OFF jumper. Be sure the heat-shrink is
transparent so that the light sensor will still work correctly.
RB02 operation. When you are ready to launch your rocket, move the jumper on J2 from the OFF
position to the ON position. Similarly, when you have recovered your rocket and want to turn off
the RB02 remove the jumper from J2. Stow the jumper in the OFF position so you don’t lose it.
The list below explains the actions of the RB02 after it is turned ON. Figure 5 shows these in flow
chart format.
1. The LED will blink twice.
2. The RB02 will beep for two seconds,
3. The LED will blink twice.
Figure 3. RB02 battery
