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This 2.4 transmitter module will operate with a 1976 or later Kraft 7C or Signature Series transmitters.
Housed in the Kraft AM case is the 2.4 module itself, the interface electronics, 2.4 antenna, LED's (visible through the 1/8" hole just behind the antenna mount, see photo - white pointer is pointing at hole) and bind button (black button right side of module).
The output of this 2.4 Tx module is for JR/Spektrum receivers either DSM2 or DSMX as determined by the receiver it is bound too.
There are 4 modes of operation;
DSM2 22ms frame rate
DSM2 11ms frame rate
DSMX 22ms frame rate
DSMX 11ms frame rate
Note; 11ms frame rate or high speed receivers can cause analog servos to jitter, use digital servos on these receivers.
Some ESC's will not operate with high speed receivers.
I also recommend that you swap channels 1 & 3 (elevator, throttle) on your transmitter. Throttle should be channel #1 which allows you to take advantage of JR/Spektrums fail safe. You may still plug in Kraft 72 or Ham modules into your transmitter. In these airplanes you will have to swap the elevator and throttle servos at the Kraft receiver.
Note; many ESC's have a fail safe built into them - low throttle in the event of a problem. These ESC's will not recognize a hold as that is also a good set of servo pulses.
When using the 2.4 Tx module in your 7C or Signature Series transmitter, you will note that the RF meter on the transmitter is indicating some value. The meter will operate but it does not indicate anything except there is power to the module. The RF meter may have different readings depending on battery voltage etc. As long as the RF needle moved, aprox mid scale or so - its ok.
The battery voltage meter on the transmitter has not been changed and will work as always. This meter should be between 9.6 and 11.4 volts for flight.
Do not use Li batteries or batteries that are higher than 11.4 volts for the transmitter or 2.4 module.
Do not use the Kraft “Buddy Box” feature with the 2.4 module installed.
Do not use the 2.4 module without its 2.4 antenna.
Do not use this circuit with a 5C or 3C transmitter.
Do not fly unless the 2.4 module LED (visible through 1/8" hole behind antenna mount) is solid green
The telescoping metal antenna should be removed from the transmitter when using 2.4 or at least collapsed into the case.
*The telescoping metal antenna should be removed from the Kraft transmitter OR at least collapsed inside the case. An extended metal antenna close to the 2.4 antenna will kill your range.
*With the Kraft Tx off, plug in the 2.4 module.
*You need to adjust the 2.4 antenna so it does not point at the model when flying. You may also bend the antenna away from the pilot but be careful in this position when laying the transmitter on its back,
*Power on - The LED's (seen through the 1/8" hole just behind the antenna mount) will flicker then come on solid green. You may now turn on your receiver.
The black bind button on the right side of the TX module has two functions.
#1 - If pushed and held when the transmitter is on, the RF output is significantly reduced. Use this feature as a range test. You need to get 30 paces (90') from your model. When the button is released the RF output is restored.
Note; 2.4 module LED's will be solid red in range test mode.
#2 - Used to bind Tx to Rx.
Bind - Tx to Rx
#1 - Plug bind jumper into bind port of Rx.
#2 - Power on Rx, LED(s) in Rx (and satellite receivers) will flash fast.
#3 - Set sticks (and switches) on Tx to desired fail safe. Neutral and LOW Throttle, trims too.
#4 - Push and hold the black bind button on the right side of the 2.4 Tx module and then turn on the transmitter.
Note, your Tx should NOT be right on top of the receiver. Move away a few feet.
The LED'# (seen through the 1/8" hole behind antenna mount) will flicker and then green LED will blink - you may release the bind button.
#5 - In a few seconds, the 2.4 module LED will be on solid green and the flashing LED's in the Rx (and satellite receivers) will be on solid and everything will operate.
#6 - Turn Rx and Tx off.
#7 - Unplug bind plug from Rx.
Turn on Tx first, when 2.4 module LED is solid green you may turn on the receiver.
Do not fly unless 2.4 module LED is solid GREEN.
*The Rx servo outputs should be:
#1, Throttle #2, Aileron #3, Elevator #4, Rudder
#5, Landing gear (Sig radios swap ch 5 & 7, Ldg is ch 7 on Sig) #6, Aux 1 #7, Aux 2 (Ldg on Sig)
* If flying electric, the Kraft throttle servo reversing switch needs to be “reverse” for most ESC’s.
* The Rx antennas (or satellite receivers) should be as far apart as possible and on different planes, one vertical and one horizontal.
* Several servos can cause voltage dips and cause a brown out with your JR/Spektrum receiver. You may want to consider 5 cell 6 volt Rx batteries or if you are flying electric use a BEC of 5.5 volts.
Any Questions - Please ask.