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Old 01-22-2008, 06:48 PM
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Default RE: Futaba FF3 Transmiter, Toast??

Biscuit, a lot of electronics have a diode on the battery + line that prevents damage. Sometimes. Have you put the battery in correctly and checked it yet??

The diode sometimes acts as a fuse and blows. If you open the case and follow the red battery wire onto the circuit board, and follow the land pattern you should show a diode, usually a small black cylinder with a silver band on one end. If you have a ohm meter, you can check it out by touching the leads one on each end of the diode. At the lowest ohm setting you will get a short, full deflection of the needle or 0 on a digital. or open, no movement on the needle or high numbers or infenity shown on the digital meter. Now reverse the leads. The oposite reading should take place from the first. If the reading is the same, the diode is shorted, unlikely or open. You can place a jumper across it for testing and see if the radio works now. If the reverse polarity got through the diode into the circuits though, a proper burial for the transmitter is in order.