rsieminski

I'd like to sensitize the throttle at around 70%, to aid in hovering. Kinda hard to explain. So that it's like neg expo at around 70%, without changing the entire throw with simple expo to the whole thing.

YNOT

You fly with a gyro, too?

rsieminski

No, no gyro, but the powerband seems to hit hard on this engine(mag .46) right at hover rpm, which makes it like in-between clicks.

ChuckAuger

My Feedback: (12)

Try a different prop

Wings-RCU

My Feedback: (2)

You can easily change that mechanically. Just make sure the servo arm is pointing almost directly at the engine at full throttle and 90 degrees at idle. Remember though throttle will come up very quick from idle to about half throttle and half throttle will only be six or seven clicks up from idle on your transmitter stick.

jon595

My Feedback: (2)

Are you talking about setting a throttle curve? Slave throttle to throttle and adjust from there.

Jon

rsieminski

"Slave throttle to throttle and adjust from there." How do I do this? I don't know what you mean by "slave"? Do you mean mix?

jon595

My Feedback: (2)

Yes, mix throttle to throttle. I do not have a Futaba but I got the idea from RCM magazine and the guy was talking about your radio. It worked on my JR 8103. This is what you want.

Jon

ChuckAuger

My Feedback: (12)

What Wings was talking about is changing the throttle linkage geometry to get a different throttle operation. You can change the angle where the servo arm is at neutral with the throttle at idle, change the angle of the throttle arm on the carb, etc.

The linkage length will change, but the linear travel is a lot less if, for instance, your servo arm is at 90 deg at idle, and pointing at the engine at full stick..the last half of stick doesn't move the carb arm hardly at all.

Conversely, if the servo arm is pointing straight back at idle, you get a lot more travel on the thottle in the lower half of the stick.

You can make the throttle behave very differently with some geometry finesse.

Back before radios had end point adjustments, you learned how to make them do all sorts of things..this just trying to get it wide open at full throttle and closed at full down trim.

Getting the control surfaces to go up and down was easy..getting the throttle to work perfectly without binding was WAY harder.

Thank god for computer radios and end point adjustments!!! Now even throttles are a piece of cake.

And take the throttle ratchet off...I use a heli radio and have no "clicks" on the throttle..just smooth power/

Flyfalcons

Use a point mix, throttle-throttle and adjust the point curve so that at 75% throttle the engine calms down a little.

rsieminski

Chuck,
I completely understand now! I'll give it a shot, along with straight expo, I should be able to get the desired result.

Flyfalcons,
I've been playing with it for about an hr. Unfortunatly, I think I only have that option in heli mode. That's what I was looking for. I'll try to get it without the radios help. Thanks!

Flyfalcons

My only experience with this radio is helping a friend, but I was pretty sure that the last two free mixes were set up on a five point curve, even in airplane mode. However this may only be on the Super model which you may not have.

Another possibility is to set the throttle subtrim relatively high so you have a small travel for high throttle and a large travel for low throttle. Instant poor man's throttle expo.

ScottK

My Feedback: (9)

We usually just use the expo as follows:

1) Get the Tx ready for Expo adjustment on Throttle channel

2) Start the plane

3) After the engine's warmed up, advance throttle to exactly half-stick on Tx

4) Have buddy run the expo while you hold the plane vertical

5) Adjust so that the plane just holds it's own weight (hover)

Now test-hover some, and adjust a few percent either way until you like the response.

rsieminski

Flyfalcons,
Yes! That is exactly what I was looking for! It's hard for my brain to understand though? pos1 to 5 and values from -100% to pos 100%. I tried and got the barrel go back and forth 3 times in a single stick motion???? Any idea what sample values I could use as a starting point?