The "Buddy Box" or Flight Training System
If you are just starting Radio Controlled Model Flying you are strongly advised to join your local MODEL FLYING CLUB as this gives access to a Flying field, Insurance and most importantly, a BMFA Qualified Instructor. Please print this page off and let your Instructor read it or refer him to it. Your particular club may have local requirements or arrangements that differ from this article. Your Model Shop will put you in touch with a local club or visit the Flying Site Finder for a list of UK sites and clubs. Before you do anything consult your club members.
Frequency Discipline
When using your 'Buddy Box' you must at ALL TIMES abide by the club procedures regarding Frequency Allocation and Control. BEFORE you learn to fly make sure you are familiar with all the requirements. An important part of the BMFA 'A' certificate is a full understanding of the various frequency systems in current use. If you are the direct cause of an accident you can be held legally responsible, you will not be very popular in the club if you destroy someone's model through carelessness or stupidity. See Note (b)
When learning to fly on a Club site the 'Buddy Box' or Trainer system is now more or less mandatory. If you are the member of a club that provides a fully equipped Model Aircraft c/w Radio Gear, Engine and a Buddy Box facility you are indeed very lucky and most, if not all of the information below will not be required. Flying solo WITHOUT a BMFA 'A' Certificate on a Club Site is usually against club rules and may even invalidate your insurance.
However if you are just starting, or considering taking up Radio Control Model Flying as a hobby, the few notes below may be of interest. No doubt you will have already spent a not inconsiderable sum on setting yourself up with an Engine, Model, Radio Gear etc., and it may come as a surprise to find that you are now more or less obliged to purchase a SECOND Transmitter and a suitable Buddy Box Lead, before you have even had time to use the first one.
You can of course beg or borrow a second Tx. (Transmitter) on an "as required basis", but this is most unsatisfactory for a number of reasons and these have been listed below.
1) The TX's. may be electronically incompatible. see Note (a)
2) If the Master (Instructor's) TX is in daily use it will need to be reset, Trims, Throws etc. to suit your model each time you have a training session. See (10)
3) If you swap TX's. about then every time you alter the Master TX you will need to go through (2)
4) There are at least 3 common types of TX Buddy plug. This give at least 6 possible leads, and buying a full set is clearly not an option. There is little point going to your site hoping someone may have a suitable lead in his flight box for a TX that you have to (hopefully) borrow on the day.
5) Modellers are understandably reluctant to allow someone to alter their TX settings when it is currently in use.
6) The Trims and Travel on the Master (Instructor's) and Slave (Pupil's) TX's. need to set to give the same flying characteristics.
7) There is not always a suitable TX available.
8) Even if the Club provides a TX (2), (4) & (6) will still apply.
9) The TX may not be dedicated for Training use only.
10) Most modern TX's. offer some form of VDU (Visual Display Unit) and sophisticated computer software that allows a range of different models to be set up and stored for recall at will. With careful planning these can overcome many of the above problems.
Note (a) JR TX's. have a different order of Sync pulse, for example pulse (1) may be the Throttle on a JR TX but the Aileron's on a Futaba TX etc. This can be overcome by some very sophisticated electronics, but the cost and trouble are not worth it. It is also something else to go wrong. Before purchasing a second or slave TX make sure it will operate as required. Try before you Buy.
Overview
As you can see from the above the only complete long term solution is to buy your own personal second Transmitter and a Trainer Cord. (Buddy Box Lead) Provided the second TX is compatible with your main TX it need not be state of the art. For example it requires neither a Xtal (Crystal) or a Battery (Ni-Cad) and as long as it has a pair of Control Sticks that may be all that is required.
You should also give careful consideration to the new generation of 2.4GHz sets now gaining popularity. See Note (b) below.
Modes **
Before we start it may be of some use to describe the two Main Modes of Transmitter (TX) control. (sometimes referred to as A & B Modes) There is also Modes 3 & 4 but these are little used.
Mode 1 has the Rudder on the Left Stick, East/West, with the Elevator North/South. Ailerons are on the Right Stick East/West with the Throttle North/South.
Mode 2 has the Rudder on the Left Stick East/West, with the Throttle North/South. Ailerons are on the Right Stick East/West with the Elevator North/South.
Mode 2 is the Normal set up and generally to be preferred, but this is a personal choice. Speak to your Instructor.
The Throttle is usually moved Forward to Fast. (Just like the accelerator on your car) It is usual to set the Throttle so that with the Trim lever FULLY FORWARD and the Stick FULLY BACK the engine ticks over as slow as possible, consistent with reliability, (i.e.: does not cut out) The Engine MUST CUT OUT with both the trim and the stick moved FULLY BACK. Note:- Most modern TX's. Have an Engine Cutoff switch.
Most TX's. seem to be set up in Mode 2 as purchased, so unless there is an overriding reason, stick with Mode 2 from the start. Ailerons & Elevator on the Right.
Operation
Your Instructor should set up the Master/Slave combination and also ensure that it all works correctly. When correctly set up with the model flying straight and level, switching from Master to Slave should have no effect on the model at all. Transition should be seamless. Due to the wide range of options available with modern TX's. with regard to Trainer Setup consult the Manufactures Operating Manual for full details.
Range Check
Carry out a range check on the completed setup. Switch on the Master TX (using the correct frequency peg) and walk away about 50 metres from the model. Operate the Master & Slave TX's. as you would during a normal training flight. Both units should operate the controls perfectly. Range with the model in the air is always much greater than on the ground. The Slave TX has No Battery or Xtal and the Aerial should be Retracted.
This setting procedure up takes quite a while, which is why it is better to have a complete Buddy Box system of your own. You need only carry out the above procedures once and can take both TX's. and Model home leaving all trims etc. correctly set. Next time you fly you should be 100% ready to go with a fully set up system and a lot less to worry about. The second set is well worth few extra pounds and can always be sold when no longer required, usually recovering your initial outlay.
Note (b) Since this article was written (2005) there has been a significant development in Model Aircraft Radio Control Technology. This is the introduction by Spektrum, closely followed by the other major Tx suppliers with systems operating at a frequency of 2.4GHz. These latest Tx's. 'search' for a vacant frequency and lock onto it, removing the need for the traditional Xtal. If you are new to RC Model flying you are strongly advised to consider a 2.4GHz system from the start.
** 2.4 GHz is 2,400,000,000 cycles per second.
** 35MHz is 3,500,000 cycles per second
Happy Landings
Links
Text © Colin Usher 2007 Illustrations © Colin Usher 2007
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical or photocopying, recording or otherwise without the prior permission of the copyright holder. Except for private & non-profit use.