crtmmac

My Feedback: (12)

I took off and got a reasonable distance away for my departure turn. Then it all went wrong. Engine sagged then returned, erratic control surfaces, etc. A quick, but mild turn got me back on the runway, knees shaking and beads of sweat on my forehead. This was my giant P-47 witha Zenoah G-62. On the ground I did the range check again and it failed. Servo chatter, huge drain on the batteries and the TX is only about 12 feet away (antenna down). Clearly a radio issue I'm using a Futaba 7 AUF (channel 16) and a Tower Hobbies RX (Same as a Futaba 127).

I took the plane home thanking my lucky stars that I was able to bring it back at all

I changed channel on the TX (ch 38) and installed a Futaba TX - no difference

I tried a new TX on both ch 16 and ch 38 - no difference

I removed one servo at a time and tried it again - no different

I changed the RX battery - no difference

I did notice that the posiition of the RX antenna was extremely critical. I mean EXTREMELY! The antenna was run inside a plastic tube inside the fuse. I found it was better if I ran the antenna outside the fuse.

The only thing I can attribute this issue to is the fact that my pushrods are all steel wire running inside an outer plastic tube and that the antenna was too close to these pushrods.

Has anyone had a similar expereince? I'd love to hear any comments or suggestions.
thanks
/colin

Bad_Daddy

YEP! Proximity to metallic or carbon rods can make drastic differences to your receiver antenna. Metalized coverings can also prove disastrous.
btw, the problem exists whether you are using a megahertz or gigahertz range system, only the relevant distances are changed. It's even possible that one or both of your control rods is (accidentally) harmonic to your antenna's frequency, and creating a ghost echo in the incoming wave.
Welcome to the world of radio frequency interference. []

A.T.

Similar problems have been mentioned by many ever since RC was installed in model aircraft. Thread Help! - Interference problems] may assist.
see also:
Solving Range Check Failures
Further information under "Radio Systems, Accessories, Alterations and FAQ" sub section "Rubber Duckie, Micro & Whip Antenna - replace long aerials with loaded base antenna" on my web page.
Regards
Alan T.
Alan's Hobby, Model & RC FAQ Web Links

CTmike100

Would there be any way to extend the range on my [link=http://www.rcuniverse.com/magazine/article_display.cfm?article_id=593]Sky soldier[/link] even though I'm using a stock transmitter? Are there any options? Thanks!

aeajr

My Feedback: (2)

1)

What is the fuselage made of? Carbon Fiber and Metalic coverings shield the signal

Is this a new plane and a new set-up or one you have flown many times without trouble?

bruce88123

I looked at your plane. It's got a 27 MHz radio DESIGNED for very short range. The plane itself is not meant to fly very far away or in much wind. More range = Different plane/radio.

CTmike100

The fuselage is made of EPP foam. I've used the plane several times, and it flies great--it just has bad range (I can hardly turn the thing before it dies!) I was wondering.. could I extend the range by using a larger antenna OR by extending the antenna reciever wire on the plane? OR would a better transmitter fly my Sky Soldier better? (As you can prob tell, I'm new to RC flying!) Thanks!
-mike

bruce88123

Just to be clear - is it the radio or the power that is dieing so quickly. If you were to try to use a different TX it may be difficult to find one on 27MHz that is much stronger. If you did, the modulation type would probably be different so it wouldn't work with your present RX. So now you need a TX and RX. These probably would not connect to your existing servos. This is just one of many problems encountered when buying in this price range.
No - changing antenna length will not help. In fact it could make it worse by retuning/mis-matching the circuits.

I'm sorry but you have purchased a $35 toy and this is about all you can expect. Again,sorry.

Darkbird

My Feedback: (7)

On the subject of the giant P-47, you may also want to check any extensions you may have. Have a Ziroli corsair with a G-62 that had developed a very similiar problem to yours. Setup had flown and range checked fine before. Disconnecting channels didn't locate problem, only thing consistent was the enginge needed to be running to cause problem. Changed everything I could then gave up for awhile. Eventually found a bad extension(a long one) in the aileron connection. A new lead solved all problems.

crtmmac

My Feedback: (12)

Thanks. I'll try that too.

cheers
/colin

crtmmac

My Feedback: (12)

OK.
This is my first gasser and I blew it, right out of the starting gate. The problem was simple after you all pointed me in the right direction. Just in front of the cockpit and off to the right I had all my controls - RX on/off, RX charger AND (only 3/4 inch away) Kill switch and Jump Start. Ho Ho. I didn't know about the 12 inch rule for distance between the engine electronics and the R/C electronics. Now of course, everyone saying "You do have enough separation........." I pulled the two engine cables and re-installed them in the engine compartment at least 12" away from the R/C stuff (and guess what, I had to cut down those loooooong cables from the magneto). Now I can be 100 feet away with the antenna fully collapsed and no more interferrence.

Excuse me, I'm off to the field while there's, still light. But before I go. I learned a lot from your replies. Thanks guys. I hope I can reciprocate some day.
/colin