Transmitters Under The Spotlight !

Five Transmitters - Face to Face

Five of our Forum members have put pen to paper to give us their personal views on the tranmitters they are using. The pro and the cons of five well known 35mhz and 2.4gHz radio systems. The five tx's under the spotlight are the Futaba 6EX, (including the 2.4gHz version), HiTec's Optic 6, the 2.4gHz Spektrum DX7, Futaba's CAP 7 Tx and the Futaba FF9.

Futaba EX RadioFutaba 6E** Series
(by Dave Bran aka 'Bravedan')

Having three differing types of this type of transmitter, I’ll list each one’s attributes and then comment generally.

However, I’ll comment on the case and sticks and other controls first, as they all share an identical build.  I fly Mode 2.  Overall the case is quite comfortable to hold....I fly with thumbs on sticks and no neck support.

The sticks are adjustable for length via a screw clamp action on the stick end, it works, but even with my average adult hands I find them too long and therefore slow to act on anything other than the shortest setting.  Spring weighting is OK and the throttle ratchet is OK and balances resistance with being safe from accidental light movement without being too intrusive.

Trim controls are digital and operate with an audible beep, in the hopes of preventing accidental action from going unnoticed.  Most times it does!  The trim controls for Rudder and Aileron are not centred under the sticks, but inboard, a stretch for a thumb in a hurry!

6EXAP (Aircraft only)
This has a rotary potentiometer on Channel 6 for proportional Flap, etc.

While you can set a model name to help remember what aircraft each memory is for, this name does not appear while you are moving through the set, which really is a major and unforgivable omission!!!

Good range of settings, End Point Adjust, Exponential, Dual Rate. One programmable mix.Range is excellent, and has been quite glitch resistant.

6EXP (Joint Aircraft and Helicopter)
This has a switch for Flaps, which doubles as Throttle Hold for Helis, so is not proportional in action.The trainer switch is dual throw for use as Idle Up in Heli mode. You get used to it but it’s less than ideal.Some labels are reverse printed from the 6EXAP, and so more difficult to read in sunlight.It has TWO programmable mixes.

Range is excellent, and has been quite glitch resistant. It DOES show the model name while changing!!

6EX- 2.4gHz
The short antenna is OK and I don’t feel affects the “balance” in your hand at all, but I know some feel it does. Its current drain is significantly less than its forbears above, so battery life is extended.

It too has TWO programmable mixes. A model setting does NOT link to the Rx so is possible to set and attempt to use a “wrong model” memory. Range is superb, Link is bullet proof.

Generically, they are good quality relatively cheap items which should give a long service life with reasonable care and are strong enough to take a few knocks.  Feel is good, and there are no serious ergonomic issues. My LMS reports VERY VERY few returns/faults.

The supplied rechargeable battery is of limited capacity, and with heavy use my first TX one lasted only nine months. Best to upgrade capacity as much as possible with the 35MHz ones (250mA drain).

The Menu system benefits from familiarity, mostly it’s logical and easy to use.

The biggest drawback is that there are only 6 model memories and no way to enhance/upgrade them. I’m getting near needing a fourth one for this reason, but it does mean you don’t have all your eggs in one basket in the event of a flat battery, broken aerial, etc.

For a budget system the 6EX range is a hard to beat combination!

(Editor's Note: As of February 2008 there is an outstanding issue in the UK regarding the 2.4gHz versions of the
Futaba 6EX and TM-7. Ripmax (Futaba's UK distributor) issued a press release regarding the problems.
Click here for more details and for the link to the Ripmax website)

Futab 7 CAP radioFutaba 7 CAP (35mHz)
By Terry Sullivan

The Futaba 7 CAP is a good all round transmitter for the intermediate flier, it would also suit the ambitious beginner. Although I do not use Heli’s, I am assured that it has all the features one needs for this, and it has the usual mixes for fixed wing, except one, which I will come too later.

I originally used a 6EXA and an older FF7. The old FF7 was good, but difficult to programme, had analogue trims and only 4 memories. The 6exa had very basic programming options and was limited in many ways. I chose the 7 CAP as an upgrade because it was good value and had the programming options I wanted It has individual switches for dual rates, which you can set as you wish. Mine also came with small stickers so that you can label them, very useful as you get used to it or let someone else try your model out! There is also a fully assignable 3 way switch, so you can set up triple rates, or use it for some other function.

Programming is very simple, it took me all of 5 minutes to get the hang of it.  Which is just as well, as the manual is not brilliant! There is also a book written by an American lady, who is some sort of bigwig with Futaba America, and available from Traplet for £19.99. In my opinion, this is a total waste of money, as the manual is actually clearer and easier to follow.

The one mix which is missing is Crow, or Butterfly mix, which is used on a glider for landing, using flaps and ailerons. It is possible to set this up, but the manual does not say how and the American lady says she knows nothing about gliders so she doesn’t know how to do this! But it is not until you get to using 4 servo wing gliders that you need this.

The specification from Ripmax website:

General System:
7 Channels
PPM/PCM 1024
Aero/Heli modes
Custom 72 x 32 display
LCD contrast (manual & auto)
Warning LED (low power)
Rotary “Jog Dial” programme selection
Digital trims with memory
10 Model memory
Stick mode selection
Selectable trainer facility

Aero Functions:
*Dual Rates - Aileron, elevator and rudder
*Exponential - Aileron, elevator and rudder
* Switch or stick selectable 
3-Circuit programmable mixing
Throttle exponential
Elevator ~ flap mix
Aileron ~ rudder mix
Air brake mix
Snap roll mix
Flaperon mix
Elevon mix
V-tail mix
Flap ~ elevator mix
Flap trim

General Functions:
Aux Ch. 5 & 7 switch selection
6 Character model name
Up/Down selectable stopwatch
Reverse - all 7 channels
PCM failsafe - all 7 channels
EPA (ATV) - all 7 channels
Sub-Trim - all 7 channels
Throttle Cut switch

Heli Functions:
Dual Rates - Aileron, elevator and rudder
Exponential - Aileron, elevator and rudder
3-Circuit programmable mixing
Hover Throttle – VR selectable
Hover Pitch – VR selectable
5 Point throttle curve 3-circuit (Normal/Idle 1/Idle 2)
5 point pitch curve 4-circuit (Normal/Idle 1/Idle 2/Hold)
Throttle Hold with rudder offset
6 Swashplate modes
Gyro mixing
Revolution mix
Switchable 2-circuit trim offset

In use, the 7 CAP feels solid and reliable. It is solidly made, easy to use, and has a good feel. Everything falls to hand easily, and does not feel flimsy. It balances well on a neckstrap, and anything that needs changing can be done easily and quickly.

In short, it is an eminently satisfactory Transmitter for all but the most advanced user. I am entirely happy with mine after 18 months of excellent service

The Tx and battery only is available (at time of publication) from Servo Shop for £125 

HiTec Optic 6 RadioHITEC OPTIC 6
Mike Stevens aka Twinstar II
I have lived with my Hitec Optic 6 for nearly two years and being fairly new to R/C flying it was my first choice of a budget entry computer radio set. The TX was purchased alone for around the £70 mark and the cost remains about the same today.

It is a basic 6 channel set suitable for both fixed wing and helicopters and has eight model memories, 4 channels on sticks, a switched fifth for undercarriage etc and the sixth is on a variable control which can be variable functions – flaps etc. There are two potentiometers for this, one on either side of the TX depending which you find the more comfortable to use.

Other switches on the TX include trainer switch, dual rates for elevator and rudder and dual rates for ailerons. There is also a flight mode switch (free mixes) and a throttle cut switch.

On the lower front of the case is a large LCD and all the programming buttons including a throttle lock switch which prevents the throttle being accidentally opened if it is engaged. Trims are by some very neat and positive click type switches next to the gimbals. The TX can either be PCM or PPM and mode one or two.

The feel to the TX is very comfortable and rugged. I also now own a Futaba 6EXA which I considered at the time I purchased the Optic Tx and have to say that the whole finish on the Hitec item is superior. The rear of the TX has a DIN socket for trainer/connection to a flight simulator on your PC and the charging jack. There is also a module which contains the crystal and which can be replaced/upgraded for s fully synthesised one at a later date if desired – forward thinking.

The Manual is some 60 pages and takes you through the general safety issues with flying into how to set some basics through to all the functions available which cover most options – dual rates, servo reverse, exponential, crow braking, flaperon etc and of course the helicopter programmes.

I have to say that I have not used all but there are some useful ones including a landing set up at the flick of a switch and a number of mixes including two free ones on top of the usual. The TX has two timers – one for elapsed time and the other for counting up to an audible warning at a pre-set figure e.g. 10 minutes flying.

Some have said that the programming menu is not that easy but to be honest once you have got yourself into the menus I find it no more difficult than some comparable transmitters. For some of the more complicated programming I still refer to the manual but I expect this applies to some other transmitters too and may be down to the fact that I haven’t used them rather than complex programming issues.

To be honest the only real drawback I can find with use is the fact that I have used up all the memories but this would be the same of others in a similar price bracket.

I know that the equivalent Futaba TX (6EXA) can be purchased for £20 less now if you shop around but to be honest I think the HiTec optic 6 offer slightly better options, a better build quality and I am more than satisfied with its performance.

You can also read an earlier review of the HiTec Optic 6 by clicking here. (Ed).

Spektrum DX7 BannerThe Spektrum DX 7
By 'Bertie Bi-Plane'
There’s nothing wrong with 35 MHz so why bother to change to 2.4 GHz ?

Well I’ve heard that said so many times since I went and got my DX 7, but my answer has always been you won’t know till you try it. There seems to be a closer connection twixt man and machine…almost symbiotic…that you don’t “feel” with 35 MHz.

Of course the obvious advantage is the fact that there are no crystals to worry about and that there is no possibility of shooting a fellow modeller down by switching on the same frequency and the pegboard is a thing of the past…Spektrum technology sees to that.

Spektrum DX7 RadioThe transmitter itself is easy in the hand , due to excellent JR build quality, and the fact that there is no extended aerial is a definite advantage to Heli flyers. Especially in-doors.

It has both Heli and fixed wing options, and the programming is child’s play once you have used it a couple of times.
There are 20 Memories to store all your models in and there is no danger of choosing the wrong one, again the technology sorts that out. If you do make the mistake, the Rx will not arm, as all models are bound to the Tx and cannot be confused.

For the Heli flyer, it has 5 point pitch and throttle curves with graphics, loads of mixes, more in fixed wing mode, and pretty much all the switches are assignable.
Plus it has that magic 7th channel that Heli boys often need.

A 1500Mah NiMh Tx battery comes as standard, for those that want to upgrade there is a LiPo option available, but be aware of the Do’s and Don’ts of using them.

There are a number of different Rx’s available that are compatible with the DX7, so small in-door models can take advantage too, the DX6 Rx’s also work with the DX7.
The only negative point about the DX7 is that the price of the Rx’s is still quite high compared with “some” 35 MHz gear, but you don’t have to change all your Current models over in one go…Do you !!  Plus these articles are directed at the first time buyer who won’t have that problem.

Spektrum DX7  receiverTo my mind the added cost is more than outweighed by the added performance, and the feeling of being connected to the model in a way that 35 MHz does not provide.

Price wise, unless you need them, buy the set without the standard servos (if your LMS says you can’t do this they are fibbing.) and this will save you a bit of cash.

Don’t be tempted by the DX6 purely on financial grounds, you will want to upgrade later, I guarantee it.  Although it is adequate, it does not have the versatility that its big brother has, and you will be disappointed after a while. I have had cause to use the 6 and it didn’t feel right if you know what I mean.

I switched to 2.4 GHz technology and never looked back…

Futaba FF9Futaba FF9
By 'Oggy'
First of all, the blah from the manual:-
• Large graphic liquid-crystal display panel with 4 buttons and an easy set up turn-and-press Dial for quick, easy setup.
•All transmitters include all 3 aircraft types with specialized programming for each, including:
Airplane (ACRO)
• V-tail
• Twin Aileron Servos (FLAPERON and AIL-DIFF)
• Twin Elevator Servos (AILEVATOR)
• Snap Roll (4 separate directions available)
Helicopter (6 swashplate types, including CCPM, see page 82)(HELI)
• 3 Idle Ups
• Revo. Mixing
• Delay
• Throttle and Pitch Curves per Condition
• Gyro Mixing including Separate Settings per Condition
• Governor Mixing
Sailplane/Glider (3 wing types)(GLID)
• V-tail
• Twin Ailerons (FLAPERON and AIL-DIFF)
BASIC menu for quick, easy set up of less complex models.
ADVANCE menu for more complex, unique setups.
• Four electronic TRIM LEVERS for rapid yet precise trim adjustment - no remembering to “store trims” between models and
no more “bumped trims” during transport.
IDLE- DOWN (ACRO) and THR-CUT (ACRO/HELI) (engine shut off) setups to allow precise engine control for taxi and landings.
• 12 complete model memories with 6 more per optional CAMPac.
• New stick design with improved feel, adjustable length and tension.
• Triple rates available by setting dual rates to 3-position switches.
• Eight SWITCHES, 3 DIALS and 2 SLIDERS; completely assignable in most applications.
• Trainer system includes the “functional” (FUNC) setting, which allows the student to use the 9C super’s mixing, helicopter,
and other programming functions even with a 4-channel buddy box. (Optional trainer cord required.)
• Transmits in both FM (PPM) and PCM by selecting modulation/cycling transmitter. Requires receiver of proper modulation.
• Permanent memory storage via EEPROM with no backup battery to service or have fail.
• 9CA super transmitter features airplane friendly switch layout, with the trainer switch at the left hand (Mode 2), and a
notched throttle to minimize throttle changes with rudder input. Defaults to ACRO MODEL TYPE.
• 9CH super transmitter features helicopter-friendly switch layout, with idle-up and throttle hold switches at the left hand, and a smooth, ratchet-less (unsprung) throttle for perfect hovering. Defaults to HELI(SW1) MODEL TYPE.
• Gyro Mixing
• 4 Flight Conditions (NORM/OFFSET-1/2/3)(GLID2FL-C only)

Everyone got that? Good – I will be asking questions later.

Why did I choose it?
When I came back to model flying around 2002, I was doing reasonably well financially, and it struck me that models may come and go, but a tx is going to be with you for a while, so might as well buy one that I am not going to outgrow. I had a residual brand loyalty to Futaba as they had been good when I was in the hobby before, so I decided on the new on the market FF9.

What’s it like?
It is an immensely capable tx with more functionality and features than 99.9% of modellers will need (which is just as well as if you do need more your wallet is going to be lighter to the tune of most of a grand). On the other hand to get a basic four channel model flying is very easy. Don’t be put off by all the knobs and switches – it’s a pussycat if that’s what you want.

How does it feel?
Nice. It is quite ergonomically laid out, most of the switches, knobs and sticks come readily to hand. I fly thumbs, so I like short sticks. They are adjustable. It feels solid and well built. I had the cheap Futaba four channel tx as a buddy, which tended to “crunch” as I held it. No such problems with the 9.

When I bought it, it was supplied with a 700mAh NiCad. I decided that this was too small, and replaced it with a 1500mAh pack. This gave me 4 hours ‘on’ time – enough for a really good day’s flying with plenty in reserve. It now has a 2700mAh pack. Complete overkill.

A dot matrix alphanumeric LCD with basic graphics. Easy to understand once you get used to it (as with all things). It has a contrast control, which is not mentioned in the manual. To change it, with the tx switched on, hold down the END button and turn the wheel. You will bit need this function as the display never has too much contrast, but it may cause problems if you do it accidentally and find your display faded. (Don’t ask how I know.)

Basically, once you get your head around the way it works (I didn’t find it hard), you will be able to do most things you would want to. For example one of my engines has a very non-linear throttle response (a few degrees throttle change at one end produces almost no power change, but at the other end produces a large power change). This can be programmed out. Most functions can be assigned to any switch or knob you want (with some reservations – see grumbles).

If you bought one of these you might also want:-
Additional model memory or Campaq. The basic tx stores 12 model memories iirc. If you need more, go to http://www.rcworld.co.uk/acatalog/Futaba_Crystals.html and go to the bottom of the page. This is as far as I am aware, the cheapest Campaq around and has not failed me in 4 years. With this installed you will be able to store 32. Any more than that is greedy.

Also, the Futaba 9C user’s guide by Anna Marie Cross – this lady seriously knows her stuff.

So is it perfect? Of course not – nothing is. My gripes with it are-

1/. The finish is not fuel proof. The plastic chrome has bubbled where fuel has got onto it.

2/. (Not so much my grumble as one raised by my instructors when I was learning to fly.) As I said above, most functions can be assigned to whatever switch you want, but the trainer (give/take control) switch cannot. It is the switch above and to the right of the right stick. Given that most people fly mode 2, where the right stick is the primary, this means that the instructor has to take his fingers off the primary stick to give control to the stude. If you change model, then this switch defaults to the flick roll switch. Now that really keeps Instructors on their toes. However, I understand that on the later FF9 Super, this has now been changed.

3/. The front of the tx is very complex in shape, and so, difficult to clean.

Accessories Available
Synthesised 35mHz module – no need for a crystal – simply dial in the frequency you want.

2.4gHz Rf modules.

So would I buy another one?

Why Not?
Because although it is a very good Tx, I have seen all sorts of tx used, and the only one I have never seen have a problem is Multiplex.

If you need to know more the manual can be downloaded from http://manuals.hobbico.com/fut/9c-super-series-manual.pdf . It is the American version so it refers to 72mHz, but all the gen is there.

I have the old FF9. Some issues may have been sorted with the FF9 super now available.

My thanks to all contibutors to this article.
Editor, Flying Sites.