- Name: Micro Receiver
- Type: 72MHz 8 Channel Remote Control FM PPM Receiver
- Purpose: To make a very light weight receiver for my slow flying airplane.
- Size: 36mm x 28mm x 5mm (1.4" x 1.1" x 0.2")
- Weight: 2 grams (0.07 ounce)
- Power: 5 volts @ about 10mA
- Construction: The circuit was plotted on thin circuit board material (probably intended
for flex circuits) with an UltraFine Point Sharpie, then etched using normal techniques.
A "double sided" circuit was produced by putting two single sided boards back-to-back.
Surface mount components were used to eliminate the need for through-holes and to
minimize weight (and size). A few "blue wires" were designed-in to minimize the layout
area required (thus minimizing the weight). The power, servo and antenna wires are
soldered directly to the circuit board.
- Operational Description: It has a sensitivity of about 3uV, and a RF bandwidth of
about 75kHz. With my R/C transmitter, it has a range of about 1000', although I have
never attempted to fly my slow-fly aircraft at that range (it takes a long time to fly that
far!). At least 5 channels work, and judging from the O'scope traces, I believe that all 8
channels would work if I had a transmitter that could exercise them. Its light weight
allows my remotely controlled airplane to fly very slowly.
- Future Developments/Plans: Maybe make an AM version. Maybe replace two 16 pin
ICs with a small 8 pin PIC. Maybe make an infrared version.
- Status: It is wired into my airplane and just keeps on working (once I found/repaired the
cold solder joint that was making it behave erratically)!
- More Info: Ron's article