HiTec HS625MG

[David Drew]

A pal is using a Hitec HS625MG with a CSM200 gyro.

HS is designated High Speed, but it is very slow on the tail, painfully so compared with my 401/9254 combo. Is this due to the gyro being faulty, the gyro being slow, or the wrong application for the 625? (meaning high speed anywhere other than on the tail)

The heli is a Raptor 30.

Any thoughts guys?

Thanks

David

[Edders]

when you say slow do you mean the time it takes to turn?


Edders

[David Drew]

Yes, it's lazy turning & when it's on the groung and you take the rudder from left to right & back it takes ages for the pitch slider to move the full range and centre itself. My 9254 is really quick, say at least four times faster.

The linkages and mechanism are free, so it's not that.

Just wondering if the 625 isn't really suited to a tail, or it's slow with the CSM200

Thanks

david

[robgt]

It's way too slow for a tail servo.
Cheers,
Rob

[David Drew]

OK, thanks Rob......and thanks to the LHS that sold it to him as a tail servo. No names.....yet!

It'll do whilst he's still on trainer base & hovering, but 401/9254 being saved for

Cheers

David

[robgt]

but 401/9254 being saved for

Sound idea!

Cheers,
Rob

[col9]

I had a hitec on my tail that was describes as "lazy" it turned out to be the end points turned down too low on the Tx (JR X388s), they were at 24% as soon as they were over 30-40% it seemed a hundred times quicker.

col.

[marktigere1]

I run a CSM HL200 and so far no problems. Also run a LW200 on a Trex.

The servo must be better than 0.12 sec/60 to work well.

Last weekend the CSM on the Shuttle was fine in a fairly brisk cross wind. That's with a Futaba 9404 and the Trex has a 3110.

Cheers

Mark

[gazza]

Epa on the rudder channel should always have a base setting of 100%.
The actual physical travel is determined by servo-arm length & IF using a 401 the limit pot.
Tail response is then adjusted around that figure.
I like a bit more response so I have my rudder CH4 Epa (Travel menu on my JR10X) set to 110%

[David Drew]

Hi All,

Do digital servos work with normal gyros? or do they have to be paired to a digityal gyro?

Also, Gazzas advice about end points being 100%. I don't understand.

Surely an end point is to limit the travel of the slider to stop it hitting the stops before the tranny lever is fully over. How does this slow down response?

I really am trying NOT to be thick


Thanks all

David

[David Drew]

Just read some stuff about HH gyros. There the end points set the pyro rate. But what about rate gyros. Do you use end points to limit travel then?

Thanks

David

[Ade_Law]

the 625 is not a tail servo so your going to have to do some fiddlling with horn lengths/gyro limits (in the gyro) and gyro gain to get it working at its best.

its still going to be poor compared to something like a 9254 tho.

re-read the manual for the gyro and ensure its setup correctly.

Ade

[jimbob]

To clear up the end point part for you...

In gyros like the CSMs and Futabas, there is a setup procedure in the gyro that sets the mechanical travel limit of the servo. This is done with a pot on the GY401.
After this, the rudder end point adjustment in the Transmitter sets the piro rate of the heli. The more rudder the gyro see coming in from the receiver (from the transmitter) the more rudder deflection it will put on the tail, but only to the maximum set in stage 1.

Hope this helps.

[David Drew]

Thanks both...it's getting clearer

I have 401/9254 onmy helis-so no probs there. Look what happens when you try to help a pal out

David

[David Drew]

OK..here we go.

Put a new JR 8900 G servo on the CSM200 gyro.

Some times OK, but what is happening is that the tail will twitch about 10 - 15 deg one way & then immediately back to the original heading. Not a wag, but a definite twitch.

tried different servo horn lengths (now about 12mm) and gyro gain settings, but still does this.

It may be related to the engine/head speed, we are trying to get it to run at about 1700 rpm (wooden blades) so the head speed may not be high enough for the gyro.
(Any thoughts?)

We have had the tail 'wag' due too high a gyro gain, but on backing this off - very slightly- it is replaced by the 'twitch'.

Can anyone assist?

Thanks Guys,

David