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For instructions on transmitters I converted to 2.4 before 2022, look at these following pages on this website.

"Heathkit", "Proline" and "2.4 conversions...RC Accessories"

Many of my 2.4 conversions are built into the transmitter - instead of a module. Below is a set of general instructions for many transmitters including, Kraft, ProLine, S&O, Orbit, Micro-Avionics, Futaba, Controlaire, EK, Heathkit and others - since 2022. The changes since 2022, are basically two LED lights in the transmitter and minor changes in binding procedures.

The output of this 2.4 transmitter 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.

A note about receivers you may use;

JR/Spektrum has a long list of receivers. Be careful with high speed (11 ms frame rate) receivers, receivers with telemetry and receivers with flight stabilization or some sort of auto pilot. The latter two may be looking for a "handshake" from the transmitter which they wont get and the 11ms frame rate may cause servo jitter with analog servos.

Just use a good ole receiver with enough channels for your application. Note; Kraft Signature Series and ProLine (for example) place the landing gear channel at the end of the serial data - channel 7. With these transmitters, landing gear wont work with a 5 channel receiver. After-market receivers compatible with JR/Spektrum (usually named after citrus fruit) work well if they are just a good ole receivers without telemetry etc.

In most cases, I have changed the channel mapping of the transmitter. The receiver outputs are; throttle, aileron, elevator, rudder, then the aux channels with channel 5 landing gear except as noted above. This rearranged channel mapping where throttle is channel #1, allows us to take advantage of the JR/Spektrum fail safe - low throttle in the event of a radio issue.

Whats added in the transmitter?

Your transmitter has a different antenna. Do not power up the transmitter without the 2.4 antenna screwed in place. Orientate the 2.4 antenna so it does not point at the model when flying.

I added a push button to the transmitter, usually in place of a trainer switch. This push button is your bind/range test button. During normal operation; when you push and hold this button, the transmitters output is reduced for range tests and you need to get at least 30 paces or 90 feet from the model.

I added 2 LED's (lights, red and green) behind the transmitters meter that are visible through the meter and indicate mode of operation - normal operation is solid green and range test is solid red.

The RF meter on the transmitter will indicating some value. The meter will operate but it does not indicate anything except there is power to the RF section.  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. This meter is NOT an indication of battery power or state of charge.
Also note; some meters like to stick, especially ProLine. These meters can not be fixed, a light tap may wake up the meter. A stuck meter does not mean it is not working.


I usually install a 5 amp slow blow fuse inside the transmitter right next to the battery/box - that yellow thing hanging on two red wires. If this fuse were to blow, the transmitter won't work and the lights on your battery charger won't light either. I have seen this fuse blow with charging issues. Otherwise, a short with high capacity batteries will burn up wires in your transmitter

Do Not;
Do not use Li batteries or batteries that are higher than 11.4 volts for the transmitter.
Do not use the "Buddy Box”/Trainer feature with the transmitter.
Do not use the transmitter without its 2.4 antenna.

Do not fly unless the LED (visible through the meter) is solid green.


*The telescoping metal antenna should be removed from the transmitter OR at least collapsed inside the case. An extended metal antenna close to the 2.4 antenna will kill your range.
*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 meter) will flicker then come on solid green in a few seconds. You may now turn on your receiver.

The Bind/range test button has two functions.
#1 - If pushed and held when the transmitter is on, the RF output is significantly reduced and LED is solid red. 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 and the LED will be solid green.
#2 - Used to bind Tx to Rx.

​Bind Tx to Rx
#1 - Plug bind jumper into bind port of Rx. Some receivers have a push button instead of a jumper plug, push the button while turning on the receiver.
#2 - Power on Rx, LED(s) in Rx (and satellite receivers) will flash fast. If a satellite is not blinking or at a different rate - you might have a problem with the satellite wires/plugs.
#3 - Set sticks (and switches) on Tx to desired fail safe. Neutral and LOW Throttle - trims too.
#4 - Push and hold the Bind/range test push button while you turn on the transmitter.

Note, your Tx should NOT be right on top of the receiver. Move away a few feet.

The LED's (seen through the meter) will flicker and then the green LED will blink - you may release the bind button.
#5 - In a few seconds, the transmitters 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.  

Note; if the transmitters LED blinks red after a few seconds - start over and hold bind button another second after the LED blinks green in step 4.
#6 - Turn Rx and Tx off.
#7 - Unplug bind plug from Rx.


Turn on the transmitter first, in a few seconds, the LED (seen through the meter) is solid green, you may turn on the receiver and it will operate in a few more seconds.

When finished, turn off receiver first then transmitter.

***** Do not fly unless the transmitter 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. I have modified most other transmitters so there is an expanding pulse width from low to high throttle, what most ESC's want to see.
* The Rx antennas (or satellite receivers) should be as far apart as possible and on different planes, one vertical and one horizontal. Keep these antennas away from all other wires, batteries etc.
* 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.


2.4 Conversions Built into the Transmitter -

Since 2022