FMA Direct T-80RF FM transmitter

Model Airplane News, Apr 2002 by Aberle, Bob

Easy-to-use,

all-purpose control

The new FMA Direct T-80RF, 4-channel FM RC transmitter has many attributes, Including ease of operation, flexibility and affordability, and Its asso

ciated systems are perfect for RC beginners and for average sport filers who are looking for a good second radio. That means that FMA Is now a fullsystem supplier producing transmitters, receivers, servos, battery packs and accessory hardware.

TRANSMITTER

Despite its simple appearance, the T-80RF is microcomputer-controlled, provides four basic channel functions (elevator, aileron, rudder and throttle) and operates on FM (PPM) using any of the 50 RC aircraft channels available on 72 to 73 MHz. Those of you who have been intimidated by computer radios will appreciate the way the T-80RF allows you to achieve extra control functions simply by flipping a series of dipswitches.

There are four servo-reversing switchesone for each channel function- and four additional switches identified as "Mix," "50 percent," "75 percent" and "PPM." For conventional aileron, elevator and rudder control, the Mix switch should remain down; moving it up activates a built-in mixing circuit that combines aileron and elevator for use as elevons (as are needed in a flying wing) and for V-tail aircraft which don't have a traditional rudder.

The appropriate combination of the SOand 75-percent switches will operate the elevator, aileron and rudder channels at full, 75 percent or 50 percent control. Keep in mind that this function is not selective: it affects all three channels simultaneously. FMA refers to this function as "dual rates," but it isn't the kind of dual-rate operation we're accustomed to. There is no panel switch to allow you to turn the rate control on or off during flight. In effect, this is a form of endpoint adjustment that uses three discrete control positions on every channel function except for throttle. The PPM switch is the most interesting of the four. When it is down, the transmitter can control negative-shift FM receivers such as those made by FMA Direct, Futaba and Hitec RCD. Move the same switch to the up position, and it will broadcast a positiveshift FM signal that operates receivers made by JR and Airtronics/Sanwa. This feature allows you to use any receiver on the market.

For routine functions, the T-80RF has traditional ratchet-type electromechanical trim levers. The two control sticks are relatively short (only 3/4 inch) and they are not adjustable. An attachment is molded into the case front for a neck strap, but none is supplied.

A single LED light indicates the battery's remaining capacity. At full charge, the LED glows green; as the battery is depleted, its color changes to yellow; when the battery is almost dead, the LED is red (do not fly on red). If the batteries die completely, the LED will not glow at all.

SYSTEM OPTIONS

You have a choice between an alkaline battery and a rechargeable Ni-Cd for power. FMA tested a set of 8 AA cells and found that they easily provide up to 10 hours of transmitter operation. If you want to save money, this might be the way to go. If you choose the Ni-Cd-powered system, it will include an appropriate charger. If you purchase the alkalline-battery version and then decide to update to a Ni-Cd, you will have to return the transmitter to FMA Direct. The Ni-Cd pack must be hardwired owing to the limited available space inside the transmitter.

Because radio needs vary greatly among modelers, FMA Direct offers the T-80RF transmitter by itself, allowing you to choose the system that best suits your needs.

The transmitter is also available with several RC packages that include a variety of components. The first comes with a micro FMA receiver, standard servos, a NiCd receiver battery pack and a 60mA charger.

The second package, designed for small, fuel-powered models, includes an FMA Extreme 5 receiver, two S-80 microservos, a 4-cell, 180mAh Ni-Cd battery pack and a 2OmA charger.

The third package was designed for micro electric models and comes with an Extreme micro receiver, S-80 microservos and an FMA SCS SA ESC with BEC.

FINAL THOUGHTS

Ease of operation is certainly the T-80RF's primary feature. The instruction manual supplied with this transmitter is excellent in every respect. I especially liked the clear sketches that help explain the built-in mixing circuit that allows elevon and V-tail mixing.

That you have to buy only what you need is another plus. You will also find that the prices of the transmitter alone and a complete system are very competitive. The FMA Direct T-80RF is a welcome addition to FMA's line of highquality RC equipment.