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Futaba Radios and Electronics Futaba Radios, Gyros, Servos, Etc.

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Old 01-22-2009, 01:14 AM   #1
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Default 72mhz futaba 7chp won't transmit

weird issue, the tx has power, but won't transmit a signal, anybody ever heard of this? I've already tried switching around crystals, i use this tx with a heli and a plane. I reset the tx, didn't help. I think my battery is dying, it says 11 volts on the screen after charging, but 15 minutes later it will be down to 4 volts and beeping. Is this(not transmitting) a safe guard built into the radio? thanks for the help guys, i don't wanna drop a bunch of money on a new tx.
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Old 01-22-2009, 02:07 AM   #2
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I would send it ( and rx ) in for a profesional service and tune asap ! The battery could be dying , but it could also be a short draining it ( besides I would have thought it would still transmit whilst it was reading good voltage if the battery was the only fault . Or upgrade
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Old 01-23-2009, 11:32 PM   #3
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did you check the receiver? could be oil in it, try to find someone with similar radio and see if their receiver picks up your radio signal.
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Old 01-24-2009, 09:39 AM   #4
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The transmitter is switchable for modulations. You can set it for PPM or PCM. If the receivers are PCM , the transmitter needs to be set to PCM modulation and vice versa for PPM.
As for the battery, With what your describing, it sounds like the battery pack has one or two cells bad in it. It should show about 11.7-11.8 volts when fully charged. And with the quick discharge your experiencing. I would think there is a couple of cells in the pack that are bad.

Check you modulation setting first and then if that cures the problem., Get a new battery for the tranny.

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