SMALL - espritmodel.com SMALL - Telemetry SMALL - Radio
Reply
Thread Tools
Old Feb 09, 2013, 10:46 PM
3 Sons - Legos and Lift
2motheus's Avatar
Grand Rapids, MI
Joined Apr 2004
567 Posts
Discussion
Eclipse 7 servo range shortened

We have an older Eclipse 7 (non QPCM) and during the summer it was working fine for several planes. We were using a Spectra module and also a 2.4 add-on from FrSky.

We just brought it out to set up another plane and all the servos move only about 30% in the clockwise direction, as seen from the top of the servo. They move all the way in the counter-clockwise direction. The clockwise movement stops when the stick gets to about 30% travel in that direction. Nothing at all happens with the servo as you move the stick the rest of the way.

The symptom is the same on both sticks, and with both side-to-side and up-down movement of the sticks. The problem is so consistent across all channels and sticks that I don't think it is a switch or a gimbal potentiometer.

With the cold weather the transmitter has been in some pretty low temperatures out in the shop, but all the former programming is still in place.

One other interesting symptom is that the radio will not send a signal out the 72 MHz Spectra module any more. However, it does still correctly drive a FrSky 2.4 module. (With the 2.4 module is when it exhibits the partial servo movement described above.)
We have already resoldered the module connector pins and confirmed continuity out through the rubber ducky antenna mount. The pins appear to be fine.

Any ideas? We know this is an old radio and probably not worth sending in for service, but if someone has seen this behavior before maybe there is a simple answer.

Thank you,
Tim
2motheus is offline Find More Posts by 2motheus
Reply With Quote
Sign up now
to remove ads between posts
Old Feb 09, 2013, 11:39 PM
Registered User
Joined Aug 2002
5,811 Posts
Quote:
Originally Posted by 2motheus View Post
We have an older Eclipse 7 (non QPCM) and during the summer it was working fine for several planes.
We were using a Spectra module and also a 2.4 add-on from FrSky.
We just brought it out to set up another plane and all the servos move only about 30% in the clockwise direction, as seen from the top of the servo.
They move all the way in the counter-clockwise direction.
The clockwise movement stops when the stick gets to about 30% travel in that direction.
Nothing at all happens with the servo as you move the stick the rest of the way.
The symptom is the same on both sticks, and with both side-to-side and up-down movement of the sticks.
The problem is so consistent across all channels and sticks that I don't think it is a switch or a gimbal potentiometer.
With the cold weather the transmitter has been in some pretty low temperatures out in the shop, but all the former programming is still in place.
One other interesting symptom is that the radio will not send a signal out the 72 MHz Spectra module any more.
However, it does still correctly drive a FrSky 2.4 module. (With the 2.4 module is when it exhibits the partial servo movement described above.)
We have already resoldered the module connector pins and confirmed continuity out through the rubber ducky antenna mount. The pins appear to be fine.
Any ideas? We know this is an old radio and probably not worth sending in for service,
but if someone has seen this behavior before maybe there is a simple answer. Thank you, Tim
A symptom of reversed polarity

What is the battery voltage reading on screen? if about 15.5v then please refer:
. Hitec Eclipse 7 - Reversed Polarity - Prevention & Cure

Still a very strong unit, will accept the Tactic AnyLink module besides others.
In need, still worth getting a repair quote by email from:
Hitec Warranty & Service - homepage.
Note: Hitec USA only services North/South America and Canada.
"Hitec USA customer service department is available Monday through Friday*
from 7am- 4:30 pm Pacific time. Reach us at 858.748.8440 or
service@hitecrcd.com any time you have a question"
• If you are from a country that is outside North and South America, please contact the
Hitec distributor in your country for service.


Convert PPM/QPCM units to 2.4GHz - with Telemetry.
Hitec AFHSS 2.4GHz Aircraft Receivers & Modules
. Hitec USA Support Forum Sticky:
Hitec AFHSS 2.4GHz Spectra Modules, Optima Transceivers & Telemetry - FAQ & Undocumented Features
(Use I-phone or Android as a screen and/or HTS-Navi wireless to Laptop)

. Eclipse 7 - For Horizon BNF models use the Spektrum "Futaba" DSM2 module.
Lower Mast Spacer may be shortened to reduce height. Wrap with a piece of tape for a snug fit and easy removal.
. Hitec Eclipse 7 & Eclipse 7 Pro - FAQ - Setup and Additional Programming:
. Hitec Eclipse 7, Optic 6 and Prism DIY Remote 2.4Ghz Antenna Mount

. Eclipse 7 & 7 Pro - Tactic AnyLink Setup

Alan T.
Alan's Hobby, Model & RC FAQ Web Links
A.T. is offline Find More Posts by A.T.
Reply With Quote
Old Feb 11, 2013, 08:42 PM
3 Sons - Legos and Lift
2motheus's Avatar
Grand Rapids, MI
Joined Apr 2004
567 Posts
Wow, Alan!
Thank you very much for the great information. The voltage readout is normal, but the servo movement symptom is right on. We will contact Hitec and go from there.
Thanks again,
Tim
2motheus is offline Find More Posts by 2motheus
Reply With Quote
Old Feb 13, 2013, 10:41 AM
3 Sons - Legos and Lift
2motheus's Avatar
Grand Rapids, MI
Joined Apr 2004
567 Posts
P.S. regarding symptoms

Hi Alan or anyone else,

Do you think the fact that the radio transmits with the 2.4 module but not with the 72 MHz Spectra module could also be explained by damage to the two ICs you identified?

Is it possible that the 72 MHz Spectra module simply takes more power and the damaged chips are not able to drive it?

I don't want to invest the effort to change the ICs if the transmission problem indicates additional damage.

Thank you,
Tim
2motheus is offline Find More Posts by 2motheus
Reply With Quote
Old Feb 14, 2013, 06:01 AM
Registered User
Joined Aug 2002
5,811 Posts
Quote:
Originally Posted by 2motheus View Post
Hi Alan or anyone else,
Do you think the fact that the radio transmits with the 2.4 module but not with the 72 MHz Spectra module could also be explained by damage to the two ICs you identified?
Is it possible that the 72 MHz Spectra module simply takes more power and the damaged chips are not able to drive it?
I don't want to invest the effort to change the ICs if the transmission problem indicates additional damage. Thank you,Tim
1. No, did you check that they are actually damaged?, it could be another problem on the board.
Changing those diodes fix majority where the voltage shows 15.5v on screen.
If voltage is correct, then something else is wrong and board may need replacing as in the first quoted article
""1. What is the current voltage displayed? If about 15.5volts is displayed,
the over voltage typically indicates that the battery has been unplugged
and then reconnected with the polarity reversed.
Despite key way on plug, plug can be forced incorrectly into TX.
At the least, this damages both the 324 and 4066 IC.
At worst, it damages the main board and the entire board has to be replaced.
In either case the radio will have to be sent in for service.
".

2. Unlikely to be the module, but with electronics all things are possible.
Test with another Hitec module or Futaba module from Futaba Compatible Modules
e.g.the FP-TP-FM is very common in FF7 & 8UA series.
If borrowed module works AOK, then check under sub section
"Transmitter - Modules: FAQ, Pinouts and DIY Service." for information to repair your module.

Alan T.
Alan's Hobby, Model & RC FAQ Web Links
A.T. is offline Find More Posts by A.T.
Reply With Quote
Old Feb 14, 2013, 10:12 AM
3 Sons - Legos and Lift
2motheus's Avatar
Grand Rapids, MI
Joined Apr 2004
567 Posts
Alan,

The voltage readout seems correct. Only the servo movements in one direction are affected. I'm thinking that this points to the part of the circuitry that calculates or generates the wave patterns in the transmission signal. Is that done by the main chip on the main board? (Hitec does not have main boards in stock right now.)

Also - the Spectra module that won't work with this transmitter works fine in another. The 2.4 module works in this faulty transmitter as well as others.

Thank you,
Tim
2motheus is offline Find More Posts by 2motheus
Reply With Quote
Old Feb 15, 2013, 04:00 PM
Registered User
Joined Aug 2002
5,811 Posts
Quote:
Originally Posted by 2motheus View Post
Alan,
The voltage readout seems correct. Only the servo movements in one direction are affected.
I'm thinking that this points to the part of the circuitry that calculates or generates the wave patterns in the transmission signal.
Is that done by the main chip on the main board? (Hitec does not have main boards in stock right now.)
Also - the Spectra module that won't work with this transmitter works fine in another. The 2.4 module works in this faulty transmitter as well as others.
Thank you, Tim
Spectra module that won't work with this transmitter works fine in another.
Confirms Module OK.
The 2.4 module works in this faulty transmitter as well as others.
Does not use all of the 72MHz circuitry.
Confirms stick pot OK.
Further diagnosis not possible over net, much like telephoning the doctor regarding a very painful lower leg or knee when the real seat of referred pain is the coccyx.
Try a Hitec AFHSS 2.4Ghz Spectra module and if all OK (at least testing with a second type of 2.4Ghz Module), then utilise it as a 2.4Ghz Tx.
This as a second hand Eclipse, for use with your PPM Rx, is in all probability similar in price to a new board and less hassle to fit and calibrate.

Alan T.
Alan's Hobby, Model & RC FAQ Web Links
A.T. is offline Find More Posts by A.T.
Reply With Quote
Old Feb 16, 2013, 10:07 AM
3 Sons - Legos and Lift
2motheus's Avatar
Grand Rapids, MI
Joined Apr 2004
567 Posts
But you're a pretty good doctor, Alan!

I think we'll change the two chips and see if that takes care of the servo movement. Beyond that I think you're right that the investment on such an old unit won't be worth it.

Best regards,
Tim
2motheus is offline Find More Posts by 2motheus
Reply With Quote
Old Mar 09, 2013, 03:55 PM
3 Sons - Legos and Lift
2motheus's Avatar
Grand Rapids, MI
Joined Apr 2004
567 Posts
A good conclusion

Good news!

Hitec was out of circuit boards, but with a couple of hours and less than $2 in parts the radio is working again.

Entering the world of replacing surface mount components was a good adventure. Not only are the legs on the two 14-pin chips very small, but the chips, about the size of my smallest finger nail, were glued to the board. My son and I took a couple hours to complete the exchange of the two chips, losing confidence with each step that we weren't damaging something else on the board.

We turned the radio on, and were delighted that not only did the radio put out a signal, but the rudder servo moved the full range to both sides!

Our mood sombered when we realized the elevator servo wouldn't move at all. We had disabled channel 2! Back into the case we went, tracing the wires and circuit from the elevator potentiometer to the chip we had just replaced. Sure enough, the soldering iron had brushed across the top of a puny surface mount resistor (I think that's what it is) and created a solder bridge between the two ends. A quick tap with the tip of the iron removed the bridge and we're good to go!
This also fixed the issue of the radio not working at all with a 72MHz module.

Summary of symptoms:
All channels had restricted servo motion in one direction only.
Radio would emit signal from 2.4GHz module but not from older 72MHz.
Voltage readout was normal, unlike other incidents we heard of.

Fix:
Changed two chips recommended by Alan earlier in this thread.

Thank you very much, Alan for your help!

Tim
2motheus is offline Find More Posts by 2motheus
Reply With Quote
Old Apr 06, 2013, 03:49 PM
3 Sons - Legos and Lift
2motheus's Avatar
Grand Rapids, MI
Joined Apr 2004
567 Posts
Hi Mattacks,
The Eclipse 7 is already on 2.4, using a 3rd party module. For very little money you can get a transmitter module and a receiver, and continue to use these radios that we already have and are familiar with.
And when necessary we can put the original TX module back in and continue to use the 72MHz receivers.
Best regards,
Tim
2motheus is offline Find More Posts by 2motheus
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Question Hitec Eclips 7 Radio Question mikefaith Electric Heli Talk 4 Apr 22, 2005 07:11 AM
Futaba 7C vs. Hitech Eclips 7 Trekki Radios 7 Aug 08, 2004 12:00 AM
How to set model memory on an eclipes 7? j_z_123 Electric Plane Talk 4 Aug 11, 2003 02:55 PM
F/S Eclipes-7 (With Spectra Module) Perfect Condition Lv2Fly Aircraft - Electric - Airplanes (FS/W) 2 Jan 14, 2003 08:48 AM
Hitec Eclipe-7 with Eco-8 curtqn Electric Heli Talk 6 Jan 08, 2003 12:25 AM