I'm putting together a plane, and right now I'm working on the servos for the wing. The directions tell me to make sure that the servo arm is centered before connecting the pushrod to it. So, to do this, I connected the servo to the receiver, along with the battery. I made sure the battery was charged before doing this. I have a 7 channel, Tower Hobbies receiver. To be more specific.. a "System 3000". I'm using Futaba S3003 servos. I've plugged the servo into each of the channels, and none of them seem to work. My receiver is at 72.510 and so is my controller. the only thing that seems to be working is a trainer switch at the top right, and that just makes the servo glitch around a little, and does basically nothing. I have an older, Futaba FP-T5UAP controller... if that helps. I'd appreciate any input on how to make my servos center... and any other info would be very helpful.

P.S: I'm building a Mariner 40...

You said you had an "old Futaba FP-T5UAP controller"? How old is it? If it is pre 1991 [X(] that may be the problem---

well you've pretty well tried the most straightforward test you can do. And it sounds like there is nothing happening at all. If you have a voltmeter, check the voltage of the batteries in the transmitter and receiver. Transmitter should be about 9.6 and the receiver should be around 4.8. Most transmitters has some sort of meter that you can see when you turn it on. Is the meter showing a reading up in the "green" zone? Also make sure that you are plugging the battery and servo into the receiver the right way. On some connections you can put this backwards. Both brown (or black) wires should be aligned. In other words, the brown wire from the battery and the brown wire from the receiver should be plugged in the same way. If it is not obvious which way, try them both ways. Hooking them backwards will not hurt anything. Also, make sure that there is a crystal in both the receiver and transmitter. They are usually visible from the outside of each. Sometimes the crystals fall out. A crystal is a small part, smaller than a pencil eraser, with two leads coming out of it.

The controller... I believe is from.... 1994. I have a trainer that I have that was built back in 94. I have yet to fly it, due to wind and engine problems. But the controller works just find with that plane. I don't know any of the information on what that plane has in it... just that it works. I looked at the receiver and yes the crystal was in there. I'll try to find a voltmeter and check... but as of now, is there anything else that I might be able to do?

The 5UAP is a PCM transmitter. The Tower Receiver I think is not. Unless you can switch the 5UAP to straight FM, they are not compatible.

You are trying to operate the new RX with the old TX? Or the new RX with the new TX? or the old RX with the new TX?

If you don't even know which frequency the old TX is on... its probably not on the same frequency as the new RX. (same goes if operating old RX with new TX... gotta know what frequency the RX is on)

The crystals in the RX's will have a little tape flag on them telling what frequency.

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All Futaba PCM capable TX's I have seen have also been PPM capable... Check its settings. If its in PPM mode than it has a chance at operating the Tower RX if its on the same frequency.

Jim is correct. The Tower system 3000 series radios are "FM" (also called PPM)

A PCM signal might wiggle the controls erratically at best. If my 7UAP is on PCM mode the PPM RX has the servos jump a bit. (if the PPM RX is on the same frequency as my PCM TX... My other frequency RX's totally ignore the PCM signal.) When the PCM capable TX is in PPM mode the Tower System 3000 RX I have works fine.

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ASSUMING both RX's are PPM...

If the Trainer's radio syttem all works... you can pull the RX crystals and swap them. Now you can check to se f the old TX operates the new RX OK.... and if the new TX operates the old RX (don't fly that way... without confirming that there's no problems... this is just a ground check) If the new RX starts working with the crystal change and the old one stops working... you have a bad crystal.

If it passes or fails... swap the crystals back. If you proved you have a bad crystal... thats what you need to buy. (match the label on the crystal. do not put a different maker's crystal in.)

Do not swap crytals in the tX's. That is against FCC rules.