Here is a list of all the postings Malcolm Holt has made in our forums. Click on a thread name to jump to the thread.
|Thread: Futaba 14SG chat|
I am not familiar with this stabilizer but what is often required is a toggle switch which allows you to select three different modes of operation and a proportional control (usually a dial or slider) which allows you to adjust the gain from zero to maximum. This is exactly what the setup you describe provides.
You have assigned SG as the control for AUX1 on channel 7. If you check the servo monitor you will see that the three positions of the switch deliver -100, 0 and +100 and these values appear to be what is needed to switch between the stabilizer’s different modes. This is normal. There is no ON/OFF icon because SG is not operating as a switch in this situation. It is simply controlling the position of whatever is connected to channel 7. If you had assigned a stick, the servo monitor would show proportional movement between -100 and +100. Because you have assigned a toggle switch it can only output three positions. You can reverse the operation in the Reverse Menu but otherwise cannot reconfigure the operation. However, as all is working, you do not need to and need not worry.
Similarly you can check the operation of RS in the servo monitor. It moves the “Gear” channel proportionally from one extreme to the other and should adjust the Gain perfectly. Again you can reverse its direction if you wish but it appears to be working fine and you have nothing to worry about. (If you allocate a different function to Channel 5 RS will still work but you will need to re-allocate it in the Function Menu next to the new function).
In summary, as long as you check very carefully that everything on the model is working correctly before you fly, you should have nothing to worry about.
The difference between using a toggle switch as a control in the Function Menu and as an ON/OFF switch elsewhere causes a lot of confusion. If you want a bit more explanation have a look in the introduction to my 14SG book. You can read it here for free.
https://www.amazon.co.uk/dp/B00BMM9J7A (You will need to copy and paste)
Click on “Look inside”, scroll down to the Menu and click on “Controls and switches”
Edited By Malcolm Holt on 03/04/2019 21:49:02
Just occurred to me. Do you mean 30 degrees?
Yes, the exponential is working as it should.
I can't help but ask why you are only using 30% throw on the aileron servos. This places a much higher load on them and reduces the resolution. Can't you achieve the required throw by moving the connections to the horns and servo arms?
With the exponential set to -90, move the aileron stick from its central position half way to the right while watching the amount of aileron movement. Now move it from the half way position to fully right while again watching the aileron. The amount of movement in the first case should be less than in the second. What happens on your model?
You only need to assign a switch if you want to be able to switch between different rate and/or exponential settings. If you simply wish to add exponential to a model without an aileron rate switch you should remove SA by re-setting it to --.
Now go to the two EXP settings and, as noted above, set NEGATIVE values of your choice such as -20.
If you want to use more than one rate and/or exponential then leave the switch assigned. When SA is UP you will see the black arrow next to the number 1 (First rate). Any rate and exponential settings entered on this screen will apply when the switch is in this position.
Now move SA fully DOWN. You will see the arrow move to number 2 (Second rate). By default, the rates on this screen will be 100 and the exponential will be 0. Change the rate and/or exponential values to those you require for the second rate setting. You might, for example, want the rates reduced to 70 while maintaining the exponential at -20.
Finally, doing this without the model is absolutely fine. That’s what the servo monitor is for and, as it gives precise values, you can sometimes get a clearer picture of what is happening
|Thread: Laser Engines - Technical questions|
Andy, the Spacewalker is 5.9 kilos (approx. 13 lbs).
Andy, FWIW I have a 150 in my SIG 1/4 Spacewalker and the power feels about right. That said, being somewhat long in the tooth, mine is covered in nylon and then painted so is probably a bit on the heavy side.
|Thread: Futaba T14SG chat|
Because of the mixing capabilities of the transmitter, a servo can be operated by more than one control simultaneously. For example, the rudder is under the direct control of its own stick J4 but, if an aileron to rudder mix has been programmed, it will also respond to movements of the aileron stick (J1). These effects are cumulative so, if both sticks are moved simultaneously, the servo could be driven to a point at which it stalls or damages the linkages. To prevent this, the Limit Points set the maximum amount the servo can move regardless of the number of mixes affecting it.
In the above example, the limit points could be set as follows. First set the Limit Points (135) to their maximum (155). Now hold the rudder stick fully right and increase the right TRAVEL value. The rudder will move further outwards and the servo will eventually begin to buzz in complaint. Make a note of the TRAVEL value at which this happens. Set the right LIMIT value to a slightly lower number to give a margin of safety and reset the TRAVEL value to its original setting. Now do the same for left rudder.
If I remember correctly, when FASST LBT was introduced there were issues with some other-brand compatible receivers. Whether these have been resolved I do not know but, if you are not using Futaba receivers, it is probably worth checking with the appropriate manufacturers.
Personally I have never had or witnessed a issue with a Futaba FASST transmitter but, statistically, my experience is insignificant. Thousands of these transmitters are in use. A handful of posts is similarly insignificant.
|Thread: Futaba 14SG chat|
In the Model Menu, select wing type as 4AIL+2FLP. You will then see AIL, AIL2, AIL3 and AIL4 in the Function Menu. You can reassign the two Flap channels to Motor and a second elevator and then connect each servo to its own socket in the receiver. This will enable you to adjust the travel and sub-trim of each independently to achieve the best setup.
As Tom has explained above, to use a separate battery to power the receiver and servos you can connect it to any channel via a Y-lead. You will, of course, need to consult the speed controller’s instructions to see how to use it with a separate battery. Although I know how some people do this, I don’t fly electrics so am unwilling to offer advice on this part of your setup.
The R7008SB is an eight channel receiver without using S.BUS. You still have channels 5 and 8 unused. Why not use them for your other two aileron servos?
How many channels do you need in total? It would help if you could list what each is to be used for.
Yes, the throttle cut does the job and is the familiar option to most users. The point about the Futaba 14SG is that it offers the alternative of the Motor Function with a safety switch. Both achieve much the same result but the difference lies in what happens when you switch on the transmitter.
With the Motor safety switch, the transmitter sounds a warning when you switch it on if safety switch is OFF. It will not transmit until you engage the safety switch or deliberately choose to override it. The Throttle Cut works the other way round. It sounds a warning if the Throttle Cut (safety) switch is ON. It will not transmit until you turn the safety switch off or deliberately choose to override it.
As said previously, there is no right way. Personally I prefer the Motor switch as it offers an additional layer of safety but at the cost of slightly more complex programming. However, I think that the most important thing is that people should use the setup with which they feel most confident.
Stick with the Throttle Cut for now but, if you want to experiment with the Motor Function, there is an illustrated step-by-step guide in the appendices of my book. Create a new model on the transmitter and check out how it works.
There's no "right" way of doing things. The throttle cut will do the job so, as you understand how it works, I suggest you use that.
I mentioned the Motor Function because I think it offers a safer alternative but at the cost of a slightly more complicated setup. I don't understand your reference to switch G. As usual on this transmitter, you are free to assign any control or switch of your choice. Yes, the Motor Menu offers several additional options but you only have to use the ones you choose.
If you want to use the throttle cut with an electric motor, leave the setting at the default 17%. This is the motor off position on the throttle stick. (With an I/C engine, this position gives tick-over so you need to reduce the value to make the engine cut).
That said, personally I would use the Motor Function rather than the Throttle to control an electric motor and set the safety switch in the Motor menu. If you attempt to power up the transmitter with the safety switch OFF you will then be warned. If you use Throttle Cut, the warning is the wrong way round for an electric setup. You only receive the warning if the cut switch is ON. This is intended to avoid fruitless attempts at starting an I/C engine with a disabled throttle.
As always, it rather depends on which features are available and the type of model. You mention trying Throttle Hold which would suggest it is a helicopter but, as you do not mention this elsewhere, I am going to assume that it is not.
One option is to set a Throttle Curve, if you have a spare one available. Read the section in my book for a full explanation. All you will have to do is assign a switch and then set all the values in the left hand column to something like 5 or whatever gives a suitable tick over speed. Note the paragraph explaining the VPP bug.
If you do not use Idle Down for its intended purpose you could use this as the throttle cut. You could then use the Throttle Cut mix to hold the throttle. Set it in the normal way but increase the value very slightly (e.g. to 19%) rather than decreasing it to the cut position.
If neither of these options is available on your model, let me know and I'll explain how to do it with a Program Mix.
You can use the Camberflap to Elevator mix but, as I don't know how your flaps are set up, I suggest you use a Prog Mix.
Activate it on screen 2/2. At Master select H/W (Hardware) and then select the slider you have used. At Slave select Elevator.
On screen 1/2 change the value at the top of the screen by trial and error to give the required movement. Set the X Offset to +100 so that the slider takes effect throughout the full range of its movement.
|Thread: Downloading of Malcolm Holt's Futaba 14SG book|
I'm glad you find the book helpful, Robert. Your experience of the Futaba manual mirrors mine exactly. Indeed, the book originally grew out of a set of notes I wrote for myself while painstakingly working through every menu and, by a process of trial and error, observing the effect of altering every parameter.
I do have to plead guilty to a little self-interest when advising people on how to access Kindle books. If their questions go unanswered they are less likely to buy my book.
As far as Amazon subsidizing me is concerned I have to admire your sense of humour. Would you believe that, in addition to their not insignificant publishing fee, they even charge me 43 pence to deliver your book. Yes, it's an e-book! I don't think that dispensing largesse figures highly in their business plan.
Amazon provide free downloads which enable you to read Kindle books on most PCs, Macs, tablets and phones.
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