Grand Wing Servo 6- and 8-channel receivers

Grand Wing Servo (GWS) recently added a new series of RC aftermarket receivers to its growing product line. Response to the GWR-4P 4-channel receiver (reviewed in the November 2000 issue of Model Airplane News) has been very favorable, and GWS has now expanded the number of available frequencies to 45. The 6- and 8-channel offerings from GWS (the GWR-6N and the GWRD-8) are every bit as good. As with the R-4P, these new receivers are distributed by Balsa Products Engineering, and they are compatible with almost any brand of transmitter now on the market. Also, like their 4-channel sibling, these new units are a real bargain.

G-CHANNEL RX

The GWR-6N receiver is a 6-channel version of the tiny GWR-4P, but its connectors have been placed on the end of the case rather than on the top. This is especially handy when installing the receiver inside very narrow fuselages such as those of small sailplanes. Its receiver circuitry is single conversion, just like that of the R-4P. There is no FM shift selection feature (no switch!), so you must purchase the R-6N specific to your transmitter. Receivers stamped with an "F" are suitable for use with Futaba and Hitec transmitters; a "J" indicates that it's compatible with JR or Airtronics/Sanwa transmitters. Like the R-4P, the R-6N is available in 45 channels ranging from 15 to 60. The GWS receivers do not incorporate a built-in fail-safe for signal interference, as many new receivers now do, but I feel more comfortable without it since the plane's behavior is more predictable during signal interruptions.

As you might expect, the R-6N is slightly larger than the R-4P; it measures 1 1/2 inches long (including the connector pins), life inch wide and lds inch high (1h inch high measured to the top of the crystal). Including its 39-inch-long antenna, it weighs 0.3 ounce (approximately 9 grams). The connector pins will accept most popular RC connectors, with the center pin (of three) being battery-positive. The pin farthest away from the PC board is the signal pin. If you use the older style Airtronics/Sanwa connectors, be sure to use an Airtronics-provided adapter or the new Airtronics type connectors to compensate for the reversed pin polarity.

The R-6N receiver performed at least as well as the R-4P in every respect. Its range was more than 1,000 feet with the transmitter antenna fully extended and the full 39 inches of receiver antenna. I ran out of test space before it ran out of range. For outdoor application, be sure to use the full receiver antenna length. During the test, I deliberately subjected the R-6N to adjacent channel signal hits only 20kHz away, but I didn't notice any interference.

Since this receiver is so similar to the micro R-4P, the deciding factors are its weight and the number of channel functions you need. If you are flying an indoor electric model with a rudder, an elevator, and a motor control, the R-4P is the best choice. If you fly models that need extra control features, such as spoilers, flaps, or even two separate motor controls, the extra two channels of the R-6N make that possible. The difference in weight is only 0.1 ounce.

8-CHANNEL RX

The new RD-8 is more of a conventional receiver than a micro. It is still small and light, plus it is dual conversion, has eight channel functions and is FM shift-selectable. It is 1 11/16 inches long, 1 1/4 inches wide and 3/4 inch thick (including a slight projection of the crystal). It weighs 0.78 ounce (approximately 22 grams) with its 39-inch antenna. Conventional RC connectors will plug into this receiver. As with the R-6N, the older Airtronics/Sanwa connectors require an adapter. On the RD-8, the outermost connector pin is battery-negative. The middle pin is battery-positive, and the third pin (closest to the label) is the signal.

On the rear of the case is a tiny but easily accessible switch that lets you select the proper FM deviation for your transmitter. Moving the switch to its upper position (toward he edge of the case) allows you to use either JR or Airtronics transmitters; the other switch position is for Futaba or Hitec transmitters. The RD-8 is initially available in the following ten channels: 17 through 21 and 50 through 54. The R-4P was first offered in the same range, but the choices for it have since been expanded, so more options may be on the horizon for the RD-8 as well.

Electronic testing has shown the RD-8 to have excellent range, sensitivity and selectivity. My friend and fellow member of the AMA RC Frequency Commitee, George Steiner, tested the third order intercept point (30IP) of this receiver at +8 decibels, which is incredibly good. The RD-8 should operate in any field environment without problems, and even though it's small, it's capable of flying large models without difficulty.

As of this writing, Balsa Products Engineering has the RD-8 in stock, and they expect to have the R-6N by the time you read this. Considering their capabilities, you'll be pleasantly surprised at the units' low prices. The RD-8 costs $60, and though the price of the R-6N hasn't been finalized yet, Bob Peru of Balsa Products estimates a street price of about $32. If you're in the market for a lightweight, affordable, long-range, 6- or 8-channel receiver for your next airplane project, these two from GWS fit the bill nicely.