Hubins timer has a dial-up RPM pot.  

* The first 1/2 of rotation (0%-50% of travel)  corresponds to the <50% throttle setting.  That means set the pot on the timer anywhere inside the first 1/2 of rotation and you will get the <50% throttle setting.  I usually turn it  (ccw) to the low-stop then move it up a little.

* The next 49% of the rotation (51% to 99%) corresponds to the middle setting.  For this I turn the pot to the high side stop, then back it off about 1/4 of travel.  Again it does not have to be real precise - just higher than 1/2 and lower than on the stop.

* Of course for the 100% throttle setting I turn it against the high stop.


When I get to flight trimming, when I determine a good airspeed I make that the middle setting.  I then set the others +100 RPM and -100 RPM so I can go up or down as I see fit. when conditions change.

That help???

Thanks Dennis A ,I read your reply and went back to the Hubin directions and the light came on.I can't and won't tell you what I was thinking  Sometimes I just try and make things more complicated than they are.
Thanks for the reply Alan ,Once I can start to fly again I will try the 12 and 24khz and see how temps are.I see you use the 24 on your Vector setup and was just wondering about the outrunner mode. Thanks again for the pointers. 

Actually, because the Phoenix “Set RPM” mode is a trinary system, the “timers” that I produce for this mode generate only three throttle settings (or pulse widths), rather than a range of values. When the RPM pot is fully counterclockwise or nearly so, the processor generates and sends a pulse width within the Phoenix RPM #1 range (37% or 1.37 ms) to the ESC; for the RPM pot anywhere in the large middle of its rotation range, the processor sends a pulse width within the RPM #2 range (69% or 1.69 ms); when the RPM pot is fully clockwise or nearly so, the processor sends a full throttle signal (100% or 2.0 ms), to select RPM #3. The great advantage of only three settings is that, knowing which RPM is being used for the flight, the processor can intelligently choose which of the three RPMs to use as an end-of-flight warning. I’ve chosen to use RPM #1 as the warning RPM if it is not in use for the flight and RPM #3 if it is. (It is up to the user to choose RPMs sufficiently different, say greater than 500 RPM, so that the warning can be felt at the end of the flight time.)

The “Set RPM” mode of the Phoenix provides the possibility of describing a specific power system in such a way that it can be duplicated almost exactly, because an actual RPM (as well as the prop and motor and battery) can be specified. (This is in contrast to requiring the user to adjust the RPM using a tach.) Dennis Adamisin takes advantage of this by specifying the Set RPM mode for the upper range of the power systems he has developed for John Brodak.

Any “timer” that generates a full range of throttle settings can access the three Set RPM values—but none can promise an end-of-flight warning because the throttle setting they use for the warning may well be within the throttle range used for the flight RPM. It is possible to document this: my FM-2a, with two RPM pots, can be reliably set to obtain any one of the three RPMs for the flight RPM, but will always use RPM #1 for the warning. (With two RPM pots, I’m able to cover the entire throttle range and yet have fine control in the constant-RPM mode of any ESC that supports that—the Phoenix, Schulze, etc. On the other hand, if a user specifies just one mode, say the High RPM mode of the Phoenix, I can narrow the range for both pots and make fine adjustments even easier and more precise.)

Because the normally-used RPMs for any constant-RPM mode fall within a pretty narrow range of throttle values (30% to 45% gives about 9,000 to 11,000 RPM with the High Range of the Phoenix, 30% to 50% gives about 8,000 to 10,400 RPM with the Schulze, etc.), it is possible to get a fine adjustment of the RPM with only one RPM pot (e.g., my FM-2 and FM-2R). But these timers can access only RPM #1 in the Set RPM mode, in general, and would generate no end-of-flight warning.

The adjustable constant-RPM mode is attractive when developing the optimum prop and RPM for various field conditions but, once this is accomplished, the “Set RPM” has promise for making it trivially easy to select one of three known RPMs at the field, based on current field conditions, without having to use a tach. This suggests a flight manager or timer that supports both modes, selected by moving a simple slide switch. This is the rationale behind the design of my FM-6a, FM-6R, and the new FM-7 and FM-7R.