by Model Avionics
|For a review on the Throttle Jockey Pro go <here>|
Jockey RevMax by Model
So what is the RevMax and how is it different then a throttle governor? The RevMax takes over control of the throttle only when the rotor speed begins to get too high. A governor will take control of the throttle throughout the whole flight. So why wouldn't you want that? Well a governor such as the Throttle Jockey Pro does a great job, but if you are looking for the highest degree of constant rpm then the RevMax is the way to go. So what should you get, the TJPro or the RevMax? That depends on your skill level. The RevMax only engages when the headspeed gets high during the no-load sections of your routine. All other times you are in control of your throttle so you need to be proficient at setting up a good throttle curve and cyclic mixes. Okay now you're asking 'so it sounds easier to just use a governor, how much performance difference would the RevMax give?' Again this depends on how well you are at tuning the engine and how well your throttle curve and cyclic mixes are setup. With everything right it will remain locked in. With a governor there is some lag on quick maneuvers which results in less power at the points it is needed. With a cyclic mix the extra power is mixed instantly with the stick movement so you end up with a more constant rpm. While running a governor I found it worked great when doing individual tricks but I could keep a more consistent head speed throughout a routine with my own curve/mixes. However one thing I did miss was that the governor maintained a constant rpm during the no load sections of the routine. The RevMax solves this by having the advantages of manual curves/mixes as well as the governor mode during the no-load conditions. By it preventing the overspeed condition I can more concentrate on making the maneuver look symetrical and end up in the right place to flow into the next trick. For instance one trick I do is a tail stand take-off that levels out for a short distance into inverted tail-first then into a backwards outside loop followed by a backwards inside loop. Without a RevMax or governor I would have to really manage my collective when coming up to the top of the first loop. If I did not get out of the negative range and into the positive with the right timing and the right amount it would overspeed. And of course when you get an overspeed condition it does not return to normal quickly so it effects the next few maneuvers you do. Adding extra 'loading' to get the head speed down or to maintain rpm during things such as a power dive can be done by a combination of the collective and elevator. For example during a power dive you give positive collective while adding forward elevator to keep it going straight down. This does help to maintain the speed but at times it takes away from your accurancy in positioning. Also this loading move cannot always keep the rpm from going a little high. You have to work the next tricks in a way to load the engine and get the rpm down. I really like this RevMax, no loading maneuvers anymore, just concentrate on the routine.
|Installation and Setup
The first thing you do for
installation is install the magnet(s). If you do have the
stock plastic Raptor 30/50 fan then you will notice two
places on the underside of the fan specifically made for
the magnets. For other fans you will have to drill your
own holes. Before you glue the magnet(s) in place you
have a couple of questions to answer. Do you have a high
point balancer to check the fan? And if you do then do
you want to use one magnet or two?
At this stage you now have everything hooked up and you are ready for calibration. Where some people mess up here is with digital trim radios, you need to hold the throttle cut button/switch during the entire calibration process. The reason you hold the throttle cut during the calibration is to show it the entire range from engine off to engine full throttle. If you did not hold the throttle cut down then it would only see a range from 20% open to 100%. The other thing that people mess up on is with odd end points set for the throttle servo. If you have 150% on one side and 50% then it could cause problems. The end points need to be fairly close to equal and be no less then 80%. The manual wants you to have a setup of 100% both sides but I have ran it at just over 80% with no problems. BTW: If you had one end point at 150% then you were probably trying to keep the servo from binding with the cyclic mix, the best way to stop the binding is <this>. And one more thing people mess up on is not having the end points of the AUX channel set to 100% on both sides. Now with all of that in mind lets go through a setup. Turn the radio on and move the throttle stick all the way down. If you use a throttle cut switch/button to stop the engine then hold this when you get ready to toggle the switch. If you do not then make sure the mechanical throttle trim is all the way down. Now turn the receiver on and within three seconds toggle the switch for the RevMax twice. You should see the 'SET' light flash. Let go of the throttle cut button/switch and move the throttle stick all the way to the top (the LED will turn yellow) then all the way back down (the LED will turn green). Now toggle the switch twice to exit the calibration mode. I know... you thought there was more to it then that :) Quick and simple is better, I like it this way.
To set the AUX switch so you can disable the RevMax go to the end point menu in the radio and set one side to 5% or less.
Next is setting your target rpm. At this point after calibration your AUX channel is 100% for the 'on' side and 5% or less for the 'off' side. Make sure the switch is in the 'on' position then fly the helicopter and do a power dive at zero degrees collective. If you hear the rpm go high then lower the end point for the 'on' side a few percentage and try again. When I do not hear a change in rpm I know I have it right.
If you have a six channel radio and channel 5 is used to
control the gain of a gyro then there is another option.
This is only for people that are good at building
electronic projects. You can make a manual adjustment
circuit for the gain plug on the gyro. <HERE>
is one such circuit. Most of the time once you have the
gain set for the gyro you do not need to adjust it
anymore so a manual setting is not much of an
inconvenience. You can then use the gyro function in the
radio to set seperate head speeds for different flight
modes if you had the need to do so.
Tip #2: For convenience you can change the length of the sensor wire to a couple of inches then use an extension cable to connect it to the RevMax. This will allow easy removal of the engine without having to undo the cable routing to get the engine out.