dkshema
rrProfessor
Location: Cedar Rapids, IA
| The bind plug for the receiver plugs into the slot where the pigtail from the switch harness would go -- the RX battery slot. If you intend to bind using the switch harness, the binding process requires that you use a switch harness that has all three wires -- the red, brown, and ORANGE lead you'd typically see in a JR heavy duty switch harness. In an FM/PPM system, the three-wire harness is also required to use the Direct Servo Control (DSC) cable that allows you to control the servos from your TX without having to turn the TX on.
A switch harness that does NOT bring out the third pin from the RX battery slot WILL NOT LET YOU GO INTO BIND MODE.
In any event...when you bind your RX to the TX, the RX learns the position of the sticks, and uses those positions as the fail safe setting. At least that's what the manual leads you to believe. In reality, the only control that gets a fail safe setting during the bind process is the throttle channel. All remaining channels in the DX7 are set to hold the last known position when fail safe is activated.
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The DX7 is supplied with two bind plugs. One is a female plug (to mate with the charge lead on the JR/Spektrum Heavy Duty switch harness), the other is a male plug (as you'd find on a servo lead).
The male plug is handy if you're flying an electric chopper in which you would normally plug the combination ESC/BEC into the throttle channel of the RX.
If you had an electric heli in which power would be applied to the throttle channel plug by your ESC/BEC, you'd plug the male binding plug into the empty battery slot of the DX7 RX when you applied power to the RX through that ESC/BEC in the throttle channel.
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If you take a look at the typical JR/Spektrum servo or battery plug, you'll see three wires...the red one in the middle is + power from the battery. The brown one on one end of the connector is the battery GROUND wire. The orange wire on the opposite end of the plug would be the signal wire for the servo, over which the servo gets its position pulse.
In receivers that have a separate battery port, generally only two of the three pins are connected -- the center pin (+ battery), and one of the outer pins (battery ground). The third pin would be not connected. In the case of the DX7, however, grounding that third pin as the bind plug does, puts the receiver into bind mode when power is applied.
(In the case of JR receivers, that third pin on the battery plug is dedicated to the DSC function, but that's a whole different story).
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The bind plug simply ties the two outer pins of the connector together, and it gets plugged into the RX BATTERY slot. In order to put the RX into BIND mode, you MUST tie the two outer pins of the BATTERY port together. Power is applied as usual through the center pin.
So, your switch harness is the culprit, it does not allow you to ground the third pin of the battery connector when power is applied to the RX, and therefore, you're not getting into bind mode.
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The solution? Disconnect your switch harness from the RX battery port. Insert the MALE bind plug that came with your DX7 into the battery port of the RX.
Plug your battery into any unused channel on the RX. If you don't have an unused channel, temporarily unplug a servo so you can plug the battery into its slot. You don't need to have a servo plugged in to set the fail safe or to bind.
If you don't have a bind plug, take a servo extension cable and cut off the female end. Solder the two outer wires (orange and brown) together. Plug the male end into the RX battery slot. Voila, instant home made bind plug.
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With the bind plug inserted into the RX BATTERY slot, the battery plugged into any available slot, turn on the power to the receiver. LEDs in both the main RX and the satellite RX will be flashing.
Set your throttle stick to LOW, set all other sticks to neutral on the TX. Push the BIND button on the back of the transmitter WHILE you are turning the transmitter on. The bind button MUST be pressed when you power up the TX to put the TX into bind mode.
Let the TX and RX do their bind thing. Both LEDs in the main and satellite RX's will go solid when binding is complete.
Turn the RX off, REMOVE your bind plug. Plug your battery back into the battery port, and if you disconnected a servo, plug it back into the appropriate slot.
You're done.
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Remember -- in the DX7 the ONLY function that actually gets a user-selectable fail-safe position is the Throttle channel. All other channels are programmed to hold their last known position for the duration of the event that put you into fail safe.
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* Making the World a Better Place -- One Helicopter at a time! *
Dave |
