Dang missed the Spartan Gyro on ReadyHeli

[Buzzkill]

Didn't get home until late. Checked my e-mail, in stock hurried to the site to order one. Out of stock. :thumbdown:

Anyone got a line on it instock anywhere?

[boya]

Hey, Buzz... is this gyro any good?

[Buzzkill]

Apparently the got one in stock and it sent the e-mails to everyone on the list DOH!!!!

They say they'll have the "big" shipment in the next week or two.

Everything I've read says it kicks the other word for donkey.

Bad side, it fries Futaba S3154 servos. So if you get one, better get a new tail servo too.

[capebob]

I was sitting at my computer when I got the email that they were available. I immediately clicked on "add to cart", alas too late.:bawlI can wait.
Bob

[Angelos]

Bad side, it fries Futaba S3254 servos. So if you get one, better get a new tail servo too.

I assume you mean S9254, but who said it fries them? I have been using the same S9254 on one of our test helis for over a year now. And a customer has reported that to his amazement his Futaba S3154 was still cool after several minutes of 3D on a 450 size heli while it was always worryingly hot with his previous gyro.

-Angelos

[dDavid]

I've missed it 3 times! I should be on their "direct call" list instead of the email reminder.

[Buzzkill]

I meant Futaba S3154 and I have corrected the post.

So your saying there is no issues with the Futaba S3154 and the Spartan 760? If so this is great news and I stand corrected.

I will be getting one and trying it out as soon as it is availible.

[rotorhead58d]

on finless bob's video review for the gyro, it says in the instructions that the s3154 is "not suitable". also, if someone is using a 3154 for the tail on his trex 450, he is gonna be in big trouble. it's a little small for that application isn't it?

[Buzzkill]

Let's see what Angelos has to say. I hope I'm wrong.

[Angelos]

The S3154 has a history of getting warm and slowing down or quiting in flight. If used correctly on a small heli with balanced tail it can be a good performer. As a precaution it was originally excluded from our list of suitable gyros but since many of them are in use successfully it was later added. The most important factor here is not which gyro you use but to ensure that the helicopter does not demand much torque from this tiny servo.

-Angelos

[Buzzkill]

As soon as I can get one I'll post up what happens. At the very least it would seem there might be issues with the S3154. What I posted earlier was based on information I read from Spartan that stated they had removed the S3154 from there suitable list due to excessive heat.

I would very much like to read that information was wrong.

[rotorhead58d]

thats one of the reasons i went with a S3153mg for the tail. i just figured if it had a problem with any gyro, i would stay clear of it. i have heard zero bad reports about this servo. from what i have seen so far, the sparton gyro looks like a great pick for this heli. nice and small.

[robl]

I'm not sure I understand the reasoning for this heli. The spartan as I recall is light by 450 heli standards. It is still like 16 grams. It also won't work with the logictech 3100 servo which seems to be the best servo for the tail on this heli.

I have the 3153 non MG version. Its not a bad servo. But its not superfast for sure. The question on these little birds, is what servo you could run with the spartan? IMHO, a 3154 connected to a spartan is just a waste of money. The really fast servos are all too large for this bird. Hobbycity has a knockoff logictech 3100 servo that could probably work, as does rctek. But at that point, Its cheaper, easier and lighter to just buy the logictech combo.

[Angelos]

The ds760 works with the logictech 3100 servo. It is included on our website and user guide. In fact now every digital servo works with the ds760 with the right settings. So even if it is not included in our lists drop us a line and we will figure out what setting you need to use.

FYI... this servo is manufactured by a company in Asia and is rebranded for other companies. You will find it as Logictech 3100G, Robbe FS 61 BB Carbon Speed Digital, and many others.

-Angelos

[robl]

from what I understand, the logictech 3100 version is made to use the superfast digital mode on the logictech gyro. The other copies cannot use that mode.

[Angelos]

All modern digital servos can take 333Hz; what you call super fast. This is in fact the default setting of the ds760. I have a Robbe FS 61 BB which certainly works happily at 333Hz and presumable all other versions of this servo will do too.

-Angelos

[robl]

okay, just saying what I had read at other places. There is a knockoff of that servo sold by hobbycity that claims it won't work with the ds mode on the gy401, so something has to be different somewhere I would think.

[Steve Evans]

All modern digital servos can take 333Hz; what you call super fast. This is in fact the default setting of the ds760. I have a Robbe FS 61 BB which certainly works happily at 333Hz and presumable all other versions of this servo will do too.

-Angelos

The Logictech 2100T supports 3 servo speeds (in the words of the manual).

1. Dedicated Digital Servo(LTS-6100G)
2. Matched Mini Servo
3. Mini Servo for general

For most of us the selection will be either (3) for an analogue servo, or (2) for a digital servo.

I have hooked up an oscilloscope to measure the pulse width and period and have found the following with ATV/EPA set to 140% as per the Logictech setup instructions, limits cleared, and with HH off:

1.
min: 720us
mid: 980us
max: 1240us
frame rate: 3.6ms (278Hz)

2.
min: 1080us
mid: 1450us
max: 2080us
frame rate: 3.6ms (278Hz)

3.
min: 1080us
mid: 1450us
max: 2080us
frame rate: 15ms (67Hz)

Option (1) clearly uses non-standard pulse widths so I'd avoid selecting that for fear of upsetting any connected servo.

Options (2) and (3) differ only in the frame rate.

Concerned that the framerate on option (2) might be too high (in light of comments I've read about S3154's failing using DS mode on 401's) and the cause of the failure of my S3154 servo I contacted Ripmax (the UK Futaba importer) who informed me that Futaba specify a minimum frame period of 3.33ms (300Hz) for their digital servos, so the Logictech timing in mode (2) looks good.

I now use a Robbe FS61BB Speed Digital servo which I can confirm needs to be used in mode (2). In mode (1) the servo only traverses through about half the movement seen in mode (2), which from the figures above is what you'd expect.

Steve