Jr. 460t gyro.........I have purchased two 460t's in the last year from two different hobby shops.......both gyro's had the problem that when I increased the gain it also caused the control surface to move to a new trim position........approx 1/8" from neutral.

I sent the gyro's back and Horizon replaced both without question but when ask if anyone else had this type problem, the answer was no...........has any else had this problem with the 460t?

Hey Two Dogs, do a search on runryder.com under the gyro section. The JR gyros 410 and 460 are really not very good gyros. I helped someone at our club diagnosis his 460 problems all summer. And it still doesn't work very well after a new replacement from JR.

First of all you have to run PCM to get them to work. They throw out way to much EMF noise. What servo do you have running on the gyro?

Seriously, my opinion on this gyro is it's junk. the Futaba 401 combo (with a high speed servo) is the best gyro for the money right now at around $180. The gyro alone is $120 I think.

I've heard many many stories about sending the 460 to JR for a replacement and the gyro still does not work correctly after they send a new one back. But it's been my experience you must run PCM also!

Tom

On the Bob Cat, what is an alternative gyro to use on the rudders??

Just curious:

Are you running PCM or PPM (FM)?
Also I assume the gyro is in rate mode or Heading Hold?


Check this post out:

http://www.rcuniverse.com/showthread...udder+gyro+jet]

Two Dogs,
I had this same problem with my bobcat 460T gyro. If you read the instructions closely on this gyro they say that it will shift center slightly when the gain is increased or decreased. I sent mine back to horizon also and they said it was normal. After being told by several of the guys at my field that it was not normal I sold my 460 and found 3 of the discontinued 450's from various hobby stores.

If you are using the 460T on the bobcat switch it out and see if you can find a G450 (highly unlikely, but maybe). It cured the problem with it switching center.

Patrick.

Hi Two Dogs,

The JR 450 and 460 gyros both will exhibit varying degrees of this drift phenomena versus the gain setting from zero drift to unacceptable offsets. Additionally, the problem exacerbates itself in some gyros as the gyro heats up during use due to thermal drift. You can read more about this at:

http://www.gajets.net/Links/Tips_and...ros/gyros.html

Most of the gyros in use today are Piezo gyros. These gyros have proven to be very reliable, however, all Piezo circuits will produce varying levels of trim changes from thermal drift. Gyros were first implemented in model helicopters where trim changes versus gain are not a significant issue. Nevertheless, trim changes versus the gain setting can be a significant problem for fixed wing aircraft.

Gyros are now available that are designed specifically for fixed wing aircraft and that either do not drift or that internally correct for drift. Some Piezo gyros, such as the ACT Wingo Gyro (Germany) and the Hobbico Airplane Piezo Gyro HCAM4010 employ a calibration procedure built in that cancels out all thermal drift. The ACT/Hobbico gyros are designed specifically for fixed wing aircraft and not helicopters. They are single axis gyros with two inputs and two outputs each of which are reversible. Therefore, you can use them on flaperons. They also have stick priority built in to them.

There is also a new technology called Silicon Micro Machine (SMM) that may eventually replace Piezo technology. SMM gyros do not exhibit any thermal drift and are advertised to be less susceptible to vibration with increased reliability. Futaba already offers SMM gyros, however, according to the Futaba web site, the Futaba SMM gyros do not work with JR digital servos. JR hasn't yet introduced SMM into its gyro product line.

Gordon Dickens
mailto:[email protected]
http://www.gajets.net