what is the proper freq. setting to use with this servo? 1520uS/333hz, 760uS/560hz, 1520uS/250hz, or 960uS/333hz. I purchased one of these to put onto a HK250 heli for the tail servo along with an Assan 250 gyro. I do not want to burn up the servo with the wrong setting has anyone else used this combination? Currently I'm using an hitech analog servo and a gyro that came from the donor heli for the electronics. It is much older technology and I would like to go digital with it for faster response and better 3D capabilities.
This is a 1520us servo. It works at least up to 333Hz (which is what the ZYX-S FBL gyro outputs for the tail servo). I use it on the tail of my HK250GT FBL and it has worked for hours, so no problem there. I used to have it on the swash as well (which operates at 83Hz with the ZYX-S), worked fine as such but they strip very easily when you crash. I have had a few "close encounters with mother earth", but so far it has not stripped (while acting as tail servo), so really happy with it, especially considering the price.
Tibor, if you just have a single servo to the RX, does the jitter disappear then? How many servos do you have connected to the RX? What is the capacity of the ESC (voltage and amps)? Do the servos work well with a servo tester? Under what circumstances do you see the jitter (motor at full throttle, or when everything is idle)? Sorry, lot of questions but it's hard to understand why you have problems without more details!
I did not test it myself. However, beastx provides a long list of servos and recommends the update frequency. This list shows only few servos that work with more than 300Hz. Thus, I would not use 490Hz. Personally, I would use not more than 100Hz since this is one of the cheapest digital servos ever.
There is generally no reason why a digital servo should not work with any receiver. Some receiver provide a special high update rate mode that is only for digital servos. Thus, analog servos can not be used in this mode. But the way around there is no problem.
I'd like to know what is the difference between the 5V and the 6V version of this servo. I know that the 6V version will handle the higher voltage, however the 5V version must have some strong points otherwise HK would just cease production and sell only the 6V version, why bother having the same servo in a weaker version at the same price? What are the strong and weak points of the two versions?
Thanks Wayneuk, but you haven't anwered my question, or maybe I haven't asked clearly. If HK has two versions at the same price, it must be pros and cons for each of the two models. I guess my real question is what are the strong points of the 5V servo?
Soulman, this servo is specified both at 4.8V and 6V, so we are not talking about two different servos, it's the same servo. If you power it with 4.8V, then you get the performance specified at that voltage. If you run it with 6V, then you get the performance specified for that. So the point is, you get a little quicker and stronger servo when you run it at 6V compared to at 4.8V. I run mine at 5.5, haven't tested neither 4.8V or 6V. You should stay within the range of 4.8 to 6V, but any voltage within the range should be OK. HTH
Lassek, very humbly, I don't think so. It's two different servos, different model number and, if you look at the pictures, one is clearly marked 5V the other 6V. I have done a bit of web research and crafted myself an answer: unlike analog servo, where 1V delta just means a bit more/less speed/torque, digital servo can maximize that 1V, run the 6V at 5V and you'll get a lot less performance (probably 30%/40%) run the 5V at 6V and you'll burn it out in no time. I guess the motor in the servo is fine tuned to the supply voltage and in digital environment 1V makes a world of difference.
Sorry Soulman, I misinterpreted the question. The HKSCM9-5 only is optimized for 5V and will fry with higher voltage. The HKSCM9-6 is specified for the whole range 4.8V to 6V, but has lower performance at lower voltages. But to address the question about the two versions, I would say that the determining factor is your ESC or BEC. If the ESC outputs 5V, then you should choose the HKSCM9-5 for best performance. But if you have 5.5V or 6V from the ESC, then you must select the HKSCM9-6 to avoid servo damage (if you want a HKSCM9 servo). In general, when I have a choice, I go for higher voltage (to reduce cable losses). When you have really strong servos, it is an advantage to go HV, in order to keep servo amperage down. For these smaller servos, this isn't so much of an issue unless you really have lots of servos in the model. It doesn't matter if the servo is analog or digital, the torque is related to the voltage. So if you would have a 6V analog servo, that servo will lose some torque and speed at 4.8V, same as the digital ones. In short, I would say that your ESC/BEC determines which servo version to choose.
I have them in my bixler, after a multitude of crashes they still work great. I have 5 of them in various foamies and have never needed to replace one..... (none of the planes weigh over a kilo). The foam may take some of the stress in crashes, or maybe they only like major crashes! I think you've been unlucky,
I wouldn't do that, the Zephyr specifies high torque metal gear. These servos are plastic gear and they don't have that much torque. I would go for XGD-11HMB or similar (cheap but metal gear, digital, ball bearing and really high torque for the size).
Dragonfly, I'm not questioning your findings,... just a thought,... maybe what your using to test them may be slightly variable as well....I wonder if you used a second servo tester whether you would get the same results on each servo?.......... I have these servo's in a few planes and I like them, there tough and have survived a few "incidents". The way I fly they just have to work, accuracy is not so important. Have a nice day
Absolutely, yes. I used 4 of these for my HK450V2, even used one for the tail servo. I had no problem with any of them. I stripped out a couple of them in a crash, but there is still at least one on the swash that has been through 50-75 flights at least, with no issues.
I eventually replaced the tail servo with a better one, but noticed no real improvement with the more expensive servo.
Could you explain what you mean with "they all differ in centre position"? Do you mean mechanically, that the servos don't have the exact same centering position when looking at the servo arms? In that case, that's just how it is... :-)
I think its normal. I have 7 of these and some are centered, some are just a bit off center. Otherwise they work flawlessly and extremely smooth and precise. You can use the sub-trim functionality on your programmable radio to adjust the center position. That way you can center all of them.
Dragonfly 21 points - 1/30/2013
It is exactly as you discribed in you following description. I have 7 of these and some are centered, some are just a bit off center. Thank you both for your answers. Regards
Does the servo tester have any variance as well?, do you get the same results with a second test unit? ....just thinking......my servo tester cost $2.50, I use it to confirm the servo actually works and to centre them on the plane, I would not rely on it for too much accuracy.
Hi can i use this servo with Rabbit FC, as a gimbal servo, where the refresh rate is 270 Hz? Will this work on 270hz or higher, because my existing analog servo works only on 50hz with Rabbit Flight controller.
These will work fine with any controller I know of.
The 6V spec. just means it will work with 5-cell nicads or with 5.5V output controllers without problem. They have one that is spec'd for 5V that is meant for 5V Max. controllers or 4-cell nicad packs.
Actually NiCd and NiMh batteries are rated for 1.2V (*5=6V) this is, of course nominal voltage and it is possible to see 1.4 to 1.5 just off of the charger, but that will quickly go down to 1.2 to 1.3V per cell.
You got my curiosity going, I have a 4 pack of nicads in my servo tester, they have not been charged for about 3 months, across this pack of 4 nicads I got 5.2volts (1.3volts each). I also have them in my transmitter which I had just charged a week ago and have not used them and they were reading 2volts each!! they are branded Ultracell 2500mah (and they do have 1.2volt written on them)............ I suspect they will be 1.2v under load,......or my multimeter is not accurate enough to get correct readings at such low voltages.
In essence you are correct they do have written on them.
I've been using them for a few months now in my Transmitter, I've only charged them once mid November, both the TX and the battery's have given me no problems, I use the TX nearly every day, for 20-40minutes depending on how many battery's I put in my planes...anyway these servo's are great!!
Well, the ESC would depend on the draw of the motor, no on the voltage the servos require. In any case, the Plush ESC supplies only 5v. The Multistar ESCs supply 5.5v so you might be better off using them.
I got some prior to go in the versus glider in yellow , can see them through the wing also I killed one when soldering cutting out the plug so if doing this be quick don't let the heat get to the main board. White is better so changed out servos in my glider no yellowing in the wing now great servo awesome price compared to other overpriced servos.
I sure hope they also change the lead wire colors to the simple red, white and black! That orange and brown is just ugly and I've hated them all the time as that also makes it hard to see them. Not critical but hey, anybody paying attention to these little things???
I'm pretty sure the colors are brand dependent. Not 100% sure but I think the Black/Red/White is what Futaba use and Brown/Red/Orange is what $pektrum use. There's also Black/Red Yellow. There's no international standard for this except they all seem to keep the red (positive) in the middle and the dark colored one is always the negative.
That servo would certainly do the job. The best thing is to find a micro servo with 5 stars and read what the reviews say. A number of them are used in 250's or 450's. Centering is very important so make sure that it's mentioned in the review. The HKSCM9 is new to the market but it's specs certainly make it a good contender at a good price.
They sure work, I have used them on both the 250's and 450's for my cheap setups.
Nice little servo, perfect for the HK-250GT! They fit the frame like a glove, unlike the HXT900s which are a very tight fit. Fast cyclic response and very accurate. They don't suck too many amps either!
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Dimensions are almost identical to the HXT900 but these are slightly thinner. Servo lead is about 6 cm shorter as well. The bonus is that they take the same servo arms as the HXT900 so I can swap them straight into one of my 450s for testing. On the bench they are easily superior to the 900 and the price difference is trivial. At a glance, the gears look to be the same as the 900 but I hope these are stronger. Flight tests to follow.