Delay screw on the GY401 gyro

[belair]

Hi,
Can someone lett me know what the settings would be on the delay screw to work with a S9205 servo? My engine trimming should be ok now but it is still hunting.
Belair

[Ade_Law]

i would take a look at the servo horn length and limit value first as well as making sure its using the full length of the pitch slider.

It may be worth trying a longer servo horn which would result in a lower limit value on the gyro first.

Ade

[belair]

Hi Ade,
I exchanged my airplanes for the Ornith with someone. He had a GY401 gyro on it and said that it worked ok. Now I put a GY401 on it but I have trouble keeping the tail steady. I can see some vibrations on the gyro itself, the servo then has like nerve ticks if you understand what I mean and when the engine stops running the servo keeps still. So I think it must be vibrations coming from the engine. What do you think?
Belair

[Ade_Law]

the 401 is generally pretty tollerant of vibes as long as its mounted on a decent pad. use the futaba mounting pad.

you will always get some engine vibes getting to the servo from the gyro on the ground so it may not be a problem.

never had my hands on an ornith so I dont know what the tail geometry is like.

when using a 9253/4 generally as long as you are using a fairly long servo horn with a limit value of around 120-140 on the gyro its going to work pretty well. however as you arent using a digital servo it is going to be worth trying different length horns and seeing how it gets on. Does it drift much in normal mode?

some pictures of the tail end with full left, full right and centre stick in non HH might be useful.

how long is your servo horn and is it at 90degs when at centre stick in normal mode.

Ade

[belair]

Hi Ade,
I posted some pictures in my gallery under "problem pics".
I hope they are clear enough for you, otherwise I'll take some new ones.
Belair (Luc)

[belair]

Forgot something Ade,
I also added some pictures of the carb. of the engine. If this setting isn't correct can this give you to much vibration on the heli?
Luc

[Ade_Law]

Assuming the tail servo isnt overtraveling the linkage that looks to be correct.

the engine mixture isnt correct tho, the screw needs to turn about 30degs anti clockwise so that it is slightly above horizontal. Wind the main mixture needle in until it stops counting how many turns it takes. It should be about 1.5 turns.

what fuel are you running on?

also, how is the gyro mounted? is it using one of the futaba gyro mounting pads?

Ade

[belair]

Hi Ade,
I'm running Wildcat fuel 15%. I'll have to turn back the engine mixture then. The needle is on 1.5 turns from full in. The padding isn't from the Futaba. I used it with 3 layers on each other and had to change that, it was to spongy. So now I'm all out of the stuff. I'm using some stuff I have left over from I do not know what but it looks the same.
On what side of the mixture screw are you looking Ade? The left or right side just above horizontal.
Belair

[Mack]

Hi Belair

May be a stupid question, but have you got the little switch on the gyro on the non digital servo side?

[Ade_Law]

if it was set to digital it wouldnt work as it is an analogue servo and wont support the higher frame rate.

the right side of the screw should be above horizontal.

if the pad is too hard or soft it will cause problems.

Ade

[Mack]

This is true ops: ops:

[belair]

I tried it again tonight and when I connected the glowplugdriver to the external glowplug lead ( you know the ones that make it easy so you don't have to take of the canopy) the tail servo got all nerves. The engine wasn't running at that time.
Belair

[Mack]

Thats fine Belair. The GY401 is so sensitive that if you fart in the same room it buzzes

[belair]

Is it possible that the engine is jamming the receiver?
Belair

[belair]

Maybe this is a stupid question but I have a Futaba R137F receiver, does the batterie lead go in the channel 7/B ?
Belair