Receiver (Rx) Regulator
by Tony van Roon

Rx Downconverter
Parts List:
 C1 = 10uF/16V                   IC1 = LM7805 or LM7806 (see text)
 C2 = 1uF/10V                     D1 = 1N4001 diode
 C3 = 0.1uF (100N), ceramic       Cooling for IC1 (optional)
 C4 = 0.01uF (10N), ceramic
A Couple Notes:
LM7805 pin-outo This is a very simple circuit but will down convert to the required receiver voltage more than adequately. For 6 volt receivers, use a 7806 regulator. If you feel that the regulator gets too hot, install a coolrib on it. But that would be highly unlikely, since receivers don't draw that much power and the 7806 can easily handle 1 amp, so I don't think a coolrib will be necessary.
If your electric motor is properly filtered for noise and spikes, the 1N4001 diode over the input/output terminals is not needed. If you do use this diode, keep in mind that it takes 0.7V.

o Designed for an electric aircraft. To save on weight and eliminate the extra rx-battery, the receiver is fed from the same battery (8 cell, 9.6v) as the electric motor. The two capacitors are used to filter-out possible spikes when the electric motor is switched on and off. A BEC or similar device is highly recommended. In fact, this simple circuit was created per request of a club member who uses this device in combination with a bec.

o Note: The 7805 regulator may not give exactly 5 volt but rather something around 4.9 - 4.97 volts. Depending on the receiver (can it handle 6V?) I would recommend a LM7806 instead. This will give between 5.3 and 5.37V depending on the manufacturer. All other component values remain the same.
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Copyright © Tony van Roon