Company History
Controlaire
Controlaire Pulse and Single Channel Systems
By Jay Mendoza
December, 2009
In this document, we will cover some of the more popular single channel tone and pulse proportional radios built by Controlaire/World Engines. These models range from a single channel tone unit to full 3-function Galloping Ghost systems. The original Mule and Ghost transmitters were designed by Jack Port, but he died at an early age in 1966 from a heart attack and therefore many of the later systems were revised and updated by Don Baisden, and Jim Lanterman, who both helped John Maloney with Controlaire products after Jack passed away.
The most common single channel Controlaire transmitter was the Mule, and this versatile model was produced for many years, starting around 1965. Originally, the Mule could be operated as a single channel tone transmitter with a tone of about 600Hz, at 85% AM modulation. The on/off switch had a double feature in that when in the off position, if the tone key was depressed, the Mule would transmit pure carrier (CW) for use with older super-regen CW type receivers. Turning on the power switch and depressing the tone key achieved normal tone operation. The Controlaire 4 solid-state super-regen receiver was the mate for the Mule, and later the SH-100 super-het was offered as an upgraded receiver. The very first Mules used a large audio output transformer with cloth wires, but later this was replaced with a miniature transformer that soldered in place on a revised circuit board. The Mule was offered as a kit, or assembled, as kits were still quite popular due to many R/C enthusiasts being skilled in electronics at that time.
The second generation Mule was referred to as the Mule Mark II. There are several version of this as the first Mark II Mules had an anodized black badge that read Mk II place on the face of the transmitter below the silk-screened “Mule”. Later versions had the silk-screening revised to include the Mk II designation. The Mark II had the upgraded tone circuit transformer, an improved output stage (selected transistor) and the on/off switch was revised such that the tone switch could no longer send carrier wave in the off position, only tone operation was possible. Modulation was increased to about 90%, improving receiver performance.
Then we have the converted Mules, which had a Baisden/Lanterman, or Jansson type pulser for pulse proportional control. These can be either an original or Mk II Mule, depending on when, and who did the modification. The original modification appeared in Grid Leaks, but was also supported by Controlaire as they offered a mod kit. Two levers and two switches were added to the back cover of the transmitter, with the pulser board on the inside of the rear cover. The vertical lever on the left controlled rudder, the horizontal lever on the right was for elevator, and the push button switch was for low throttle, the tone switch on the face of the cover was for high throttle. As you can imagine, for Galloping Ghost/pulse operation, you turned the transmitter around so the rear cover faced you, then moved the slide switch to select “pulse” and used the levers for rudder and elevator, and the push buttons on the face and rear cover for throttle. Originally, there was no trim, and the levers gave quite a bit more throw than was needed as they had no stops, so you just had to be careful about how far you moved them. Later, the levers were refined a bit and changed from white to black plastic. This conversion of the Mule gave a split dual personality; I refer to them as Schizos!
The final Mule was a single channel pulse proportional transmitter that had a paddle type control lever mounted atop the case. Moving a smaller lever connected to the paddle, which shifted it, a small amount right or left was used for trim. Early single channel Digit Midgets also used this odd control paddle. Motor control was done with a pair of tone on and tone off pushbuttons. A switch inside the case could select tone control for escapement, or turn on the pulser for pulse proportional. All Mules used a 9-volt dry cell battery, or a 7 cell NiCad.
About the time that the Mule Galloping Ghost conversions came out, another Controlaire radio made it’s debut, the Galloping Ghost. This radio was housed in the same case as the multi-channel reed transmitters, and had a cutout in the upper right hand corner to accommodate a 2 –axis joystick. This transmitter also had the same RF output meter as used in the reed sets, with the on off switch in the same location as well. A toggle switch activated tone off and on for low and high throttle. The pulse width was variable from 20-80% to 80-20% on to off ratio, and the pulse rate was variable from about 2 PPS to 16PPS depending on where you set the neutral pulse rate; 6 PPS was nominal. A second version shortly followed with a Bonner 2-axis stick as used in the popular Digimite. A single main board had all the components mounted to it and was marked: GG-1. The on/off switch was a slide type. The tone frequency was about 600Hz. Typical output power was around 175mW. A small hole in the transmitter back with an insulating rubber grommet allowed a small stub of wire to protrude and act as sub-antenna; this was used to radiate a very weak signal for range testing with the transmitter antenna removed. Power was an NEDA 9-volt transistor battery, or 7-cell NiCad.
A second version of this radio was an improved version that outwardly looked the same, but had a toggle type on/off switch. Inside, the board was marked GG-1 JL 17, presumably to indicate Jim Lanterman had laid out this revision. The pot values of the control stick were changed, and so was the pulser rate and width circuitry to reduce the width ratio shift to 30-70% -70-30% for use with Rand and other motorized Galloping Ghost actuators. The tone frequency was increased to about 800 Hz for better performance with the SH-100 and other brand of receivers. All of these versions bore an aluminum-anodized badge under the control stick with the words “Galloping Ghost” and a character of a ghost riding a horse.
The next two versions of the Galloping Ghost had a different stick assembly that looked like an O.S. type; it had a round bezel, but was molded in black plastic. This was an improvement over the Bonner stick as it afforded trims that did not move the stick, and less tension on the gimbals springs for a smoother feel. The case was smaller, the RF meter was eliminated, the electron orbiting the “Controlaire” was deleted, the circuit board was a new size and layout, the circuitry was revised with two pots and a switch inside for adjusting the rate and width, and selecting tone or pulse operation. In tone, the red motor high tone button was used to key the transmitter. A molded black plastic center loaded antenna coil replaced the open wire coil used on the earlier versions. The second of these “OS” stick versions had a revised circuit, and changes to the PC board traces, a 2 transistor multi-vibrator replaced the single transistor tone generator, both high and low motor push buttons were now black, and there was no sub-antenna hole in the rear cover. Some of these versions were offered as kits and had a power reducing 100-ohm resistor on the back of the board to make them legal for non-licensed people to build and tune. After you built it, you sent it to Controlaire, where they removed the 100-ohm and replaced it with a jumper to increase the RF output, and certified it as operating within FCC specifications. World Engines also offered a small conversion board to update all of the transmitters to selectable high pulse rate for use with dual actuators
Along with these Galloping Ghost, and Pulse systems, Controlaire offered a “Ghost” motorized actuator that gave you proportional rudder, elevator, and position able throttle control. An “NND” two transistor switcher board was offered to eliminate the need for a center tapped battery pack, and thus give the actuator more power by switching the full battery voltage across the motor, as opposed to just half of the center tapped voltage. The NND still required the use of the SPDT relay in the SH-100 however. Next, Controlaire mounted the “Ghost” actuator and NND switcher circuit on a small PC board, which included an on/off switch and connector, plugs with mates to simplify the wiring, this was the “Ghost Mark II”. There was even a dual actuator version that had relays and circuitry for high pulse rate (12-16PPS at neutral). The “Ghost” actuator had relatively low current draw and a better motor than used in the Rands, and it did not cause as much up elevator movement when signaling throttle commands. But unlike the Rand GG-Pack LR-3, the “Ghost” actuator never came with a switcher built in that could be driven from a relay less receiver, so it was less popular with other OEMs due to that.
Along with the venerable SH-100 super-het receiver came other versions. There was a revised relay-less version, and many hobbyists converted them by just removing the relay. There was an SH-112, and the SH114. These were basically an SH-100 in a “crash-proof” plastic case, and an all-in-one version that included an Adams actuator and the necessary drive circuit all on a single board for use with the Pulse Proportional Mule, or Galloping Ghost transmitters. Essentially however, they were the same electronic design, and were quite reliable. The special noise reduction circuitry was achieved by the use of shielded case transistors in the RF stages, which was simple but effective. Controlaire offered tuning instructions that enabled the user to fine-tune his receiver using a meter; most other manufacturers offered no such instructions and discouraged you from trying to tune the receiver. Of note is the fact that the antenna coil must be tuned with the aluminum case cover on, as evidenced by the hole in the top cover. The SH series was quite versatile and could be used as a relay, or relay-less receiver, and could tolerate a range of operating voltages.
It has been reported by Ed Crotty of RCHoF that some of the Galloping Ghost versions used the same case as the World Engines/Controlaire Digital-3 channel, which was never released in any great numbers due to other issues. Ed noticed the words “Digital” are silk-screened on the case, but the Galloping Ghost plaque located beneath the control stick covers them up. This would not be unusual, as noted above; the GG-1 versions used the multi-channel reed transmitter cases. Typical efficient use of existing manufactured stock, as opposed to scraping it and re-tooling.
Due to the very simple circuitry, (only seven transistors) the use of the popular, but inexpensive Bonner stick, the attractively machine turned metal case, low cost, and a kit version being offered, Controlaires were quite popular and sold in large numbers from 1966 to about 1970, when the price of digital proportional dropped so low as to make pulse proportional impractical. Additionally, World also offered the Controlaire GG systems with a variety of actuators, including the very popular Rand GG-Pack, which used an LR-3. The main drawback of the Controlaire GG-1 systems was that they were not easily adjusted for the amount of control throw, and this was essential to have in order to prevent the actuator from cycling at full control stick throw. Most modelers devised a plywood overlay plate for the control stick to limit its full up and full right/left travel to deal with this issue. The later “OS” versions had control pots inside for these adjustments.
Although these Galloping Ghost radios are by far the most common, and thus readily available, today, most of the Controlaire transmitters we have seen are off frequency up to 2KHz on the high side. They also often are under modulated and lack output power due to aged transistors, which need replacement, and the pulser rate is often way too fast as the electrolytic caps have lost capacitance and are leaky. Most of them are now over 40 years old and have problems associated with the components aging, as noted above, and are therefore usually not functioning correctly, if at all. Additionally, the plastics used in the Bonner sticks has shrunk and distorted with age, causing the gimbal bales to no longer fit in the pivot points and bind.
It is also evident that there were issues with the actual circuit itself. There were many changes made to the modulator, pulser, and tone generator, all in an effort to resolve stability problems. It is not uncommon to find different values of components on the actual circuit than listed on the schematic. One of the reasons the Controlaire Galloping Ghost design was a bit flakey was due to the use of the bare minimum of transistorized stages (7), presumably this was done as a cost savings; transistors were expensive in the 1960s! The transistor themselves are also partially to blame for the above noted variations; they were not very consistent as compared with ones made only a few years later, necessitating some changes of other related component values. Later designs by other companies like Ace, were far more stable, and versatile, they accomplished this by using more transistors (11), but by the early 1970s, pulse proportional, and Galloping Ghost in particular, was on it’s way out as low-cost digital proportional radios replaced it. Like almost any new or novel technology, by the time it is fully refined and mature, it’s obsolete!
