7.0 volts on Spektrum???
11-18-2007, 07:09 PM
#1
7.0 volts on Spektrum???
Gents
I discovered a peculiar situation today while performing the final rigging of my latest project. one of my 5cell 1100mah nicad packs would not operate my spektrum receiver hot off the charger. it indicated 7.0volts and 6.7 with a 1amp load applied.
it powered up the receiver (lights illuminate etc.) and would operate the steering servo, retract and brake valve but none of the primary flight controls. I discharged the pack to roughly 6.5volts (6.1volts under 1 amp load) and it worked just fine.
anyone else experience this phenomenon?
BTW i put a call into John Redman and he mentioned they've successfully operated the spektrum receiver at over 8.0volts off a hot Lipo pack. soo......I might have a goofy receiver but thought I'd give yaw'll a heads up.
cheers
buck
I discovered a peculiar situation today while performing the final rigging of my latest project. one of my 5cell 1100mah nicad packs would not operate my spektrum receiver hot off the charger. it indicated 7.0volts and 6.7 with a 1amp load applied.
it powered up the receiver (lights illuminate etc.) and would operate the steering servo, retract and brake valve but none of the primary flight controls. I discharged the pack to roughly 6.5volts (6.1volts under 1 amp load) and it worked just fine.
anyone else experience this phenomenon?
BTW i put a call into John Redman and he mentioned they've successfully operated the spektrum receiver at over 8.0volts off a hot Lipo pack. soo......I might have a goofy receiver but thought I'd give yaw'll a heads up.
cheers
buck
11-18-2007, 08:09 PM
#2
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RE: 7.0 volts on Spektrum???
NiCads........ Paleeeezzzzzzzzzzzzzzzzzzzzzeeeee..... Mr one flight wonder......
You gotta slap some dual Fromeco 52 hundizizzles in that bad boy!!!
You gotta slap some dual Fromeco 52 hundizizzles in that bad boy!!!
11-20-2007, 01:12 AM
#9
RE: 7.0 volts on Spektrum???
Just spoke w/ Buck and it appears that the problem is actually caused by the amplified Y-harness servo extensions - not the Spektrum AR9000 RX. He'll do some more tests to confirm and post the results tomorrow.
2G1C - spewing my Scotch out my nose....
Barry
2G1C - spewing my Scotch out my nose....
Barry
11-20-2007, 05:06 AM
#10
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RE: 7.0 volts on Spektrum???
I tried using the amplified Y harness in my gassers.........sometimes they work and sometimes they don't. I put a call into Horizon and they said not to use this type of y harness[8D]
11-20-2007, 09:19 AM
#11
RE: 7.0 volts on Spektrum???
Sorry about your difficulties Buck. Do not use amplifiers with Spektrum! The following is from Horizon's website:
Q: When using long servo leads and/or Y-harnesses, should I use amplifiers, chokes or other filters?
A: No. Spektrum’s 2.4GHz system is immune to interference caused by long servo leads and there is no need to add filters. In fact, some types of amplified Y-harnesses won’t operate with the Spektrum system.
Here's the full article:
http://www.horizonhobby.com/Articles...ID=1624&Page=2
Q: When using long servo leads and/or Y-harnesses, should I use amplifiers, chokes or other filters?
A: No. Spektrum’s 2.4GHz system is immune to interference caused by long servo leads and there is no need to add filters. In fact, some types of amplified Y-harnesses won’t operate with the Spektrum system.
Here's the full article:
http://www.horizonhobby.com/Articles...ID=1624&Page=2
11-20-2007, 11:46 AM
#12
RE: 7.0 volts on Spektrum???
Joe
thanks for the help.
I vaguely remember referencing that some time ago but didn't have any problem when setting up the jet initially. Ofcourse, I was using an old reliable 4cell bench pack when doing initial rigging.
The up side of the delay was having a pleasant conversation with Rebecca from Fromeco.
hope to see you guys in Feb.
drinks on me @ Miramar O'Club
cheers
buck
thanks for the help.
I vaguely remember referencing that some time ago but didn't have any problem when setting up the jet initially. Ofcourse, I was using an old reliable 4cell bench pack when doing initial rigging.
The up side of the delay was having a pleasant conversation with Rebecca from Fromeco.
hope to see you guys in Feb.
drinks on me @ Miramar O'Club
cheers
buck
11-20-2007, 12:00 PM
#13
RE: 7.0 volts on Spektrum???
Buck,
Check out this post by Matt:
http://www.rcuniverse.com/forum/fb.asp?m=6649504
Its in reference to problems with JR servos on Futaba PCM and FASST receivers, but it may be the same problem with Spektrum RX's. In short, an RX with a modern processor inside may only put out signal pulses that are 3.3V high and some servos look for pulses in reference to their supply voltage. When the supply voltage is too high, they don't see the 3.3V pulses from the RX. It seems even more likely since some of the outputs (steering servo and valves) worked and others didn't. It may be also the reason some amplifiers don't work with the Spectrum systems...
Bob
Check out this post by Matt:
http://www.rcuniverse.com/forum/fb.asp?m=6649504
Its in reference to problems with JR servos on Futaba PCM and FASST receivers, but it may be the same problem with Spektrum RX's. In short, an RX with a modern processor inside may only put out signal pulses that are 3.3V high and some servos look for pulses in reference to their supply voltage. When the supply voltage is too high, they don't see the 3.3V pulses from the RX. It seems even more likely since some of the outputs (steering servo and valves) worked and others didn't. It may be also the reason some amplifiers don't work with the Spectrum systems...
Bob
11-20-2007, 01:27 PM
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RE: 7.0 volts on Spektrum???
Joe - I happen to be using long servo leads for the elev and rudder, they have chokes on them, is it OK to use them with my DX7? Everything seems to work fine. I don't want to redo it if I don't have to.
Thnx,
Bob
Thnx,
Bob
11-20-2007, 04:44 PM
#18
RE: 7.0 volts on Spektrum???
ORIGINAL: bob1393
Joe - I happen to be using long servo leads for the elev and rudder, they have chokes on them, is it OK to use them with my DX7? Everything seems to work fine. I don't want to redo it if I don't have to.
Thnx,
Bob
Joe - I happen to be using long servo leads for the elev and rudder, they have chokes on them, is it OK to use them with my DX7? Everything seems to work fine. I don't want to redo it if I don't have to.
Thnx,
Bob
I don't have any personal experience with this. If you have had many successful flights on it than I'd be prone to keeping it as is. Otherwise change it, since it is much simpler to change out two leads than build a new plane!
