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<DIV><FONT face=Arial size=2>Reminds me of the fiber optic unit I used to use in
my 40% planes where I would mount the throttle servo right at the
firewall. It had a unit at the rx end that plugged into the rx, then ran a
fiber optic cable up to the throttle servo where another decoding
unit hooked up with the servo and a power wire ran to the ignition
battery. The optic cable only served as the signal. Worked
good. They're still available I think.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<BLOCKQUOTE
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=d.pappas@kodeos.com href="mailto:d.pappas@kodeos.com">Dean Pappas</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=nsrca-discussion@lists.nsrca.org
href="mailto:nsrca-discussion@lists.nsrca.org">NSRCA Mailing List</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Thursday, August 10, 2006 11:42
AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [NSRCA-discussion] ESC and
RX intereference</DIV>
<DIV><BR></DIV>
<DIV><SPAN class=601541415-10082006><FONT face=Arial color=#0000ff size=2>Hi
Gang,</FONT></SPAN></DIV>
<DIV><SPAN class=601541415-10082006><FONT face=Arial color=#0000ff size=2>The
real fix (or at least part of it) is a cheap plastic optical
fiber link. The folks at Smart-Fly (the obvious website) created one, and
the market didn't materialize. I have a prototype, but a 5V supply at the ESC
end will have to be created that runs from the big battery. Maybe the
microprocessor supply on the ESC can be tapped for the optical receiver. The
problem, even though all these ESCs are opto-isolated, is that the
ESC/servo lead is still an antenna that runs deep into enemy
territory, picking up motor and ESC induced crud and putting it into
the RX ground. That corrupts the receiver's measurement of the received
signal. Dave's ferrite donut helps this. The biggest sources are the big
battery leads, and the three motor wires. The big battery wires should be
twisted, or at lest tied together so that any AC current ripple in those
wires does not have a big loop antenna with which to braoadcast magnetic noise
fields. Those big capacitors on the input of the ESC do not completely
flatten the current coming from the batteries, and in particular the big caps
used are useless at several MegaHertz . </FONT></SPAN></DIV>
<DIV><SPAN class=601541415-10082006><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=601541415-10082006><FONT face=Arial color=#0000ff size=2>The
same is true for the three motor leads: they have 35 volts of square wave AC
with lots of current. Both the electric and magnetic fields are considerable,
but if short and twisted or tied together, they become less effective
radiators of RF. OIf course, distance is king. The optical link woiuld then
allow you to keep any radio wiring far from the power
system.</FONT></SPAN></DIV>
<DIV><SPAN class=601541415-10082006><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=601541415-10082006><FONT face=Arial color=#0000ff size=2>An
electronics hobbyist could build a cheap fiber link with maybe $20 in parts
from Digi-Key. </FONT></SPAN></DIV>
<DIV> </DIV>
<P><FONT face="Times New Roman">Dean Pappas</FONT> <BR><FONT
face="Times New Roman">Sr. Design Engineer</FONT> <BR><FONT
face="Times New Roman">Kodeos Communications</FONT> <BR><FONT
face="Times New Roman">111 Corporate Blvd.</FONT> <BR><FONT
face="Times New Roman">South Plainfield, N.J. 07080</FONT> <BR><FONT
face="Times New Roman">(908) 222-7817 phone</FONT> <BR><FONT
face="Times New Roman">(908) 222-2392 fax</FONT> <BR><FONT
face="Times New Roman">d.pappas@kodeos.com</FONT> </P>
<BLOCKQUOTE dir=ltr style="MARGIN-RIGHT: 0px">
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma
size=2>-----Original Message-----<BR><B>From:</B>
nsrca-discussion-bounces@lists.nsrca.org
[mailto:nsrca-discussion-bounces@lists.nsrca.org]<B>On Behalf Of
</B>DaveL322@comcast.net<BR><B>Sent:</B> Thursday, August 10, 2006 11:04
AM<BR><B>To:</B> NSRCA Mailing List<BR><B>Subject:</B> Re:
[NSRCA-discussion] ESC and RX intereference<BR><BR></FONT></DIV>
<DIV>With my Abbra, I had throttle glitches (but no radio holds) and no
amount of re-routing wires or antenna helped. 3 different RXs made no
difference (2 770s and 1 649, all SC JR). Adding a choke (the iron
ring thingy) to the ESC lead immediately adjacent to the RX fixed the
problem. Of note, ESCs used were CC Phx 45 and 85 and the glitching
did not occur with setups that were <55 amps. I've now run up to 85
amps no problems.</DIV>
<DIV> </DIV>
<DIV>I had the same thing with my Prestige - throttle glitches but no radio
holds. The same choke helps, but wasn't a 100% fix. Rotating the
RX 90 degrees (in any orientation) had an effect, so I picked the "best"
orientation and only an occasional throttle glitch remained. I
recently changed from the 770 to the 790 (synth SC) and that is better still
(99.9% fixed).</DIV>
<DIV> </DIV>
<DIV>Regards,</DIV>
<DIV><BR>Dave Lockhart</DIV>
<DIV><A href="mailto:DaveL322@comcast.net">DaveL322@comcast.net</A></DIV>
<DIV>Team JR</DIV>
<DIV>Team Castle Creations</DIV>
<DIV> </DIV>
<DIV> </DIV>
<BLOCKQUOTE
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px solid">--------------
Original message -------------- <BR>From: Chad Northeast
<chad@f3acanada.org> <BR><BR>> FWIW, I have an identical
equipment setup as Adam, even placing of the <BR>> gear is near the
same. We built the planes together, use the same <BR>> paint, covering
etc. The only difference is I use Futaba radio gear <BR>> (9Z, R319DPS
rx)...and have never once went into hold. I think we came <BR>> to the
conclusion that there is something going on with DC rx's and how <BR>>
they filter out noise vs. SC rx's in some setups.....as both our setups
<BR>> on DC work great, and Adam's on SC did not. <BR>> <BR>>
Maybe someone with a bit more EE knowledge could explain why this would
be. <BR>> <BR>> Chad <BR>> <BR>> Adam Glatt wrote: <BR>>
<BR>> >I'm forwarding the conversation I had with a pattern buddy to
the list <BR>> >in the hopes! it wil l save someone else's airplane.
<BR>> > <BR>> >Adam Glatt <BR>> >Team Shulze <BR>>
>Team Plettenberg <BR>> > <BR>> >-------- Original Message
-------- <BR>> >Subject: Re: ESC and RX intereference <BR>>
>Date: Wed, 09 Aug 2006 21:38:14 -0600 <BR>> >From: Adam Glatt
<ADAM.G@SASKTEL.NET><BR>> >To: <BR>> >**** <BR>> >
<BR>> > <BR>> > <BR>> > <BR>> > <BR>>
>Yikes, that sucks. <BR>> >I was going into hold about every
tenth flight with my Mantis (Xtra <BR>> >25). When I switched to the
Twister I was going into hold about three <BR>> >times a flight
(EVO). I tried everything (new TX antenna, new TX <BR>> >module, new
TX crystal, new RX crystal, new RX, twisting elevator servo <BR>>
>leads, choke on ESC line...). The only things that helped were running
<BR>> >the antenna along the wing, and switching to a JR dual
conversion <BR>> >receiver. ! Since s witching to the DC RX I've
never had a moment of hold. <BR>> >This electric motor stuff is
definitely causing interference with the <BR>> >RX. It is very
important to set your failsafe to have the throttle go <BR>> >to
idle. This way, when it goes into hold, it will chop the throttle,
<BR>> >which ends the interference. I also set my failsafe to
deflect the <BR>> >rudder a bunch so it is very obvious when hold is
occuring (good when <BR>> >trying to sort out the problem, bad when
trying to compete). <BR>> >I'm betting your only solutions are
switching to Futaba or Hitec TX+RX <BR>> >systems, or using a vastly
different receiver: JR DC, Berg 7 (just <BR>> >released), Sombra
Shadow, GWS... <BR>> > <BR>> >I have a spare ch48 JR DC RX
crystal that I can send you, and I can sell <BR>> >you a Sombra RX
through work. Other than that you'll need to source <BR>> >your
solution elsewhere. If you want to try ! the Ber g 7 I suggest <BR>>
>phoning Castle directly, as no dealers have it yet. <BR>> >
<BR>> >It's also possible that a different brand ESC will fix it. I
can sell <BR>> >you an HV85 through work for cheap. <BR>> >
<BR>> >I've been down this road. The EVO + Schulze system interferes
with <BR>> >something in the JR SC PCM receivers - that much I'm
sure of. <BR>> > <BR>> >-Adam <BR>> > <BR>>
>******* wrote: <BR>> > <BR>> > <BR>> >>Hello
Adam, <BR>> >> <BR>> >>I had a problem with my radio
yesterday and I want to check with you <BR>> >>since it maybe the
same cause as you. <BR>> >> <BR>> >>I was trying the Evo
for the first time yesterday evening at the field. <BR>> >>I
range checked before the flight but not with motor running. That may
<BR>> >>have been a big mistake now that I think about it. Anyway
the flight was <BR>> >>fi! ne unti l I got to the horizontal 8.
Just past the middle of the first <BR>> >>loop down, the motor
stopped and the control went to neutral. The plane <BR>> >>was
going down inverted at about 45 degree and hit the ground. I tried
<BR>> >>elevator and ailerons with no success. Amazingly, the
wing, batteries, <BR>> >>ESC, motor are fine. The prop just
folded, the wing didn't come off but <BR>> >>the aileron servo
gear stripped. The other servos works ok. There are a <BR>>
>>bunch of cracks in the fuse but I put everything back in place
with CA <BR>> >>and tonight I will put some glass and carbon
fibre inside. I rechecked <BR>> >>the range after the crash,
checked all connections and can't found <BR>> >>anything. My
transmitter is a 10X with the synthesizer module. <BR>> >>
<BR>> >>My friend ***** told me the ESC may have cause the fail
safe condition. <BR>> >>The motor was back ! to low throttle
before the fail safe happened. You <BR>> >>say in the message
below that you had interference this year. Was that <BR>> >>only
with the Evo and its ESC ? I had 122 flights with the std 30-10 and
<BR>> >>ESC with no problem at all with the R770 and the R2000
since around the <BR>> >>middle of Jul. I was planning flying
tomorrow with another TX & RX if <BR>> >>the plane was ready
but now I am thinking of checking the range with the <BR>>
>>motor running before going to the field again. <BR>> >>
<BR>> >>What do you think ? <BR>> >> <BR>>
>>****** <BR>> >> <BR>> >> <BR>> >>
<BR>> >> <BR>> >> <BR>> >>>-----Original
Message----- <BR>> >>>From:
nsrca-discussion-bounces@lists.nsrca.org <BR>>
>>>[mailto:nsrca-discussion-bounces@lists.nsrca.org] On Behalf Of
Adam <BR>> >>>Glatt <BR>> >&! gt;> Sent: July 4,
2006 11:10 PM <BR>> >>>To: NSRCA Mailing List <BR>>
>>>Subject: [NSRCA-discussion] WTBuy or WTBorrow: JR Dual
Conversion <BR>> >>>receiver crystals (red) ch48 and ch30
<BR>> >>> <BR>> >>> <BR>> >>>I've been
having nonstop radio interference problems this year but <BR>>
>>>finally solved it by installing a JR dual conversion PCM
receiver. <BR>> >>>However, I don't have receiver crystals for
this receiver on the <BR>> >>>channels I'm set to fly in
Muncie. I need the red JR dual conversion <BR>> >>>receiver
crystals in channels 48 and 30. I'll buy them or borrow them <BR>>
>>> <BR>> >>> <BR>> >>> <BR>> >>
<BR>> >> <BR>> >> <BR>> >>>during Muncie.
<BR>> >>> <BR>> >>>-Adam <BR>> >>>
<BR>> >>> <BR>> > <BR>> >________! _______
________________________________ <BR>> >NSRCA-discussion mailing
list <BR>> >NSRCA-discussion@lists.nsrca.org <BR>>
>http://lists.nsrca.org/mailman/listinfo/nsrca-discussion <BR>> >
<BR>> > <BR>> > <BR>>
_______________________________________________ <BR>> NSRCA-discussion
mailing list <BR>> NSRCA-discussion@lists.nsrca.org <BR>>
http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
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