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<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>>
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