Buddy Trainer Cord - 8 ft.

Trainer cords for popular transmitters. The cord allows an connection of an "instructor" system to a "student" transmitter . The student's transmitter is often with no batteries (the exception is JR) and no transmitter crystal; otherwise known as the "buddy box". Basically a bare transmitter without the ability to transmit any RF signals. Controls can be transferred to the student's box via a switch/button on the instructor's transmitter. Other than the one-way Hitec cable, all the following cords are bidirectional (either ends can be instructor or student).

Except for JR transmitters, the buddybox batteries should be removed!

If you don't see your transmitter on the list, but know that it's trainer port compatible to one on the list, then it will work with that group.
 

Type B1 - Futaba AM (DIN5)   Futaba • FG Series: FP-T7FG, FP-T6FG, FP-T5FG, FP-T4FG • FP-T4FN, FP-T5FN, FP-T6FN Cirrus • Four-XL, Six-XL
Type B2 - Airtronics Standard (DIN5)   • Radiant RD6P, RD6H • RD6000 series • Vanguard series (VG4R, VG6DR, VG6H, VG400, VG600)
Type B3 - Futaba Hitec FM (DIN6) Type B3H - Hitec "One Way" (DIN5)   Futaba • Conquest FM • FG FM • 4VF, 6VA, 6VH, 6DA, 6YF, 6YG, 6XA, 6XAs, 6XH, 6XHs • 7U, 8U, 9Z Tower Hobbies: • System 3000 4FM, 6FM Cirrus • 900FM Hitec • Focus 4, 6 • Laser 4, 6 • Flash 4, 4X, 5, 5X • Prism 7, 7X, • Eclipse 7
Type B4 - JR (mini 3.5)   • Quattro, F400, F400EX, XF421EX • XF622, XF631, XP642, XP652, XP783, XP8103 • 10 series
Type B5R Futaba 9C (square 6 to DIN6) Connect the transmitters in the B3 list above to: • Futaba 4YF, 6EXA, 9C, FF9 • Tower 4TH

• Switch OFF power on both Instructor and Student transmitters, and also switch OFF the model's receiver power.
• Remove any batteries from the student's transmitter.
• Connect one end of the trainer cord to the Instructor's transmitter
• Connect the other end to the Student's transmitter
• Switch the Instructor's transmitter to ON, and the model's receiver to ON. Make sure the servos are functioning properly
• DO NOT turn on the student's transmitter, it should be OFF at all times.
• DO NOT pull or press the trainer switch on the student's transmitter, it should not be used at any time during training.
• Set all trim levers and reversing switches on the student's transmitter to match the instructor.
• Pull or press the trainer switch on the instructor's transmitter; the student's transmitter now has control of the model. The student can move the sticks to check servos' movement as well as the direction of movement. When the trainer's switch on the instructor is released, control is transferred back to the instructor's transmitter.
• To check for exact matching of trim positions, continue to switch control back and forth between instructor and student. Adjust the student's trim position to match the instructor. Adjust until no movement on the servos is observed when control is transferred to the student.

• Switch OFF power on both Instructor and Student transmitters, and also switch OFF the model's receiver power.
• Remove any batteries from the student's transmitter.
• Connect one end of the trainer cord to the Instructor's transmitter
• Connect the other end to the Student's transmitter
• Switch the Instructor's transmitter to ON, and the model's receiver to ON. Make sure the servos are functioning properly
• DO NOT turn on the student's transmitter, it should be OFF at all times.
• DO NOT pull or press the trainer switch on the student's transmitter, it should not be used at any time during training.
• Set all trim levers and reversing switches on the student's transmitter to match the instructor.
• Pull or press the trainer switch on the instructor's transmitter; the student's transmitter now has control of the model. The student can move the sticks to check servos' movement as well as the direction of movement. When the trainer's switch on the instructor is released, control is transferred back to the instructor's transmitter.
• To check for exact matching of trim positions, continue to switch control back and forth between instructor and student. Adjust the student's trim position to match the instructor. Adjust until no movement on the servos is observed when control is transferred to the student.

• Verify both instructor and student transmitter to have fully charged batteries.
• Switch OFF power on both Instructor and Student transmitters, and also switch OFF the model's receiver power.
• Connect one end of the trainer cord to the Instructor's transmitter. The power indicator should turn ON (while the main power switch is OFF)
• Connect the other end to the Student's transmitter. The power indicator should turn ON (while the main power switch is OFF)
• Switch the Instructor's transmitter to ON, and the model's receiver to ON. Make sure the servos are functioning properly
• DO NOT turn on the student's transmitter, it should be OFF at all times.
• DO NOT pull or press the trainer switch on the student's transmitter, it should not be used at any time during training.
• Set all trim levers and reversing switches on the student's transmitter to match the instructor.
• Pull or press the trainer switch on the instructor's transmitter; the student's transmitter now has control of the model. The student can move the sticks to check servos' movement as well as the direction of movement. When the trainer's switch on the instructor is released, control is transferred back to the instructor's transmitter.
• To check for exact matching of trim positions, continue to switch control back and forth between instructor and student. Adjust the student's trim position to match the instructor. Adjust until no movement on the servos is observed when control is transferred to the student.

Hitec has released a warning on using Futaba's trainer cord on Hitec systems (here). This has caused much confusion in using a mixed Hitec/Futaba for buddy training. Unfortunately little details are given to justify forcing Hitec customers to buy Hitec trainer cables (and the usual industry standard scare tactics of burning up components and interference).

First, there are differences in the two trainer ports (Hitec vs. Futaba). On the Hitec, it is possible to disable the RF (radio frequency) section from the trainer port. This is done by connecting the appropriate pins. The Hitec trainer cable does exactly that, disable the RF section on the student's transmitter. This is the reason for the Hitec cable to be "one way", the cable must be connected correctly (since you would not want to disable the RF section on the instructor radio).

When the batteries are removed on a (student) Futaba radio, the transmitter will not have the ability to transmit RF signals, even when power is supplied from the instructor. In contrast, the Hitec radio can still generate RF signals when batteries are removed - this happens when power is supplied from the instructors radio.

To make sure the RF section is disabled, the crystal can also be removed. Since Futaba markets a buddybox (a 4VF/4YF without crystal, battery, antenna), there's zero chance that the Futaba buddybox can transmit any RF signals. "Technically" you cannot change the crystal from the transmitter (except in the case of a "module") due to FCC regulation, so removing and re-installing transmitter crystals is a no no to FCC purists.

The problem is the Futaba Trainer Cord, which has no RF disabling feature (since it can be used either connector to either transmitter). When the Futaba trainer cord is connected to a Hitec student, the student's RF section will generate signals, even if the batteries and antenna are removed. Since "technically" you cannot remove the transmitter crystal, Hitec asks you to purchase its cable (with the RF disabling feature). This is because every Hitec transmitter has a crystal (there's no Hitec BuddyBox).

So the bottom line?

• If you have a buddybox without crystal, battery, antenna (like the Futaba), then you will have no problem using this buddybox with the Futaba trainer cord (B3) on either a Hitec or Futaba instructor
• If you have a transmitter (either Hitec or Futaba) and you would like to use it as a student box, you will need to remove battery, antenna, and crystal if you are using the Futaba trainer cord (B3).
• If you are planning to use a Hitec as a student, and do not want to remove the crystal, then use the Hitec one-way trainer cable (B3H). Make sure the corresponding ends go to the corresponding boxes (instructor, student).
• NEVER has batteries in the student's box . Regardless of which cable you use, this is main cause for "smoking" incidents (when both instructor and student transmitters are turned ON at the same time).