Today's Message Index:
----------------------
1. 06:43 AM - Re: shielded 5 wire for trim servo (Robert L. Nuckolls, III)
2. 06:44 AM - Re: model airplane servo (Robert L. Nuckolls, III)
3. 06:50 AM - Re: Mounting a d-sub connector to a bulkhead as a pass-through (jhclarkfl)
4. 07:12 AM - Re: Transponder antenna signal (Marty)
5. 07:46 AM - Re: shielded 5 wire for trim servo (Etienne Phillips)
6. 07:49 AM - Re: model airplane servo (Robert Taylor)
7. 07:55 AM - Re: shielded 5 wire for trim servo (Jesse Jenks)
8. 07:56 AM - Re: model airplane servo (Eric M. Jones)
9. 08:54 AM - Re: shielded 5 wire for trim servo (Robert L. Nuckolls, III)
10. 09:04 AM - Re: shielded 5 wire for trim servo (Robert L. Nuckolls, III)
11. 12:00 PM - shielding through DB9s (Fergus Kyle)
12. 01:25 PM - Re: shielding through DB9s (Bob McCallum)
13. 01:58 PM - Re: shielding through DB9s (Peter Pengilly)
14. 02:00 PM - Sandia txp/encoder combo any good? (CardinalNSB@aol.com)
15. 02:58 PM - Re: Sandia txp/encoder combo any good? (Peter Pengilly)
16. 03:20 PM - Re: shielding through DB9s (Robert L. Nuckolls, III)
17. 03:40 PM - Re: Sandia txp/encoder combo any good? (BobsV35B@aol.com)
18. 06:02 PM - Re: Shielding through DB9s (Fergus Kyle)
Message 1
INDEX | Back to Main INDEX |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: shielded 5 wire for trim servo |
At 11:28 AM 1/16/2011, you wrote:
>I'm wiring my elevator trim servo and wondering what to do with the
>shield on the 5 wire cable that came with my kit. The Ray Allen
>instructions say nothing about it. Should I ground it at one or both
>ends, or just ignore it?
>Thanks.
>Jesse
Your choice. There is no value for having these
wires shielded so what you do with the shield
is optional and of no electrical significance.
Bob . . .
Message 2
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: model airplane servo |
At 12:48 PM 1/16/2011, you wrote:
>I agree with Bob's comments on this. I get around this problem by
>early testing to make sure that the "hard over failure" is easily
>controlled by manual override.
Good for you.
Nothing can replace the value of doing failure modes
effects analysis and/or demonstrations on a motor driven
flight control surface. See:
http://www.aeroelectric.com/articles/Trim_System_Failures.pdf
Bob . . .
////
(o o)
===========o00o=(_)=o00o========
< Go ahead, make my day . . . >
< show me where I'm wrong. >
=================================
Message 3
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Mounting a d-sub connector to a bulkhead as a pass-through |
That is exactly what I was looking for to make the connection. Thank you for your
help and to all other responders!
--------
Jack Clark
RV-8A Fuselage
http://www.mykitlog.com/jackclark/
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=327290#327290
Message 4
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Transponder antenna signal |
Stan,
Interesting post "world's fastest RV-8A", indeed. How about sharing some of
the tricks you used to achieve this goal. You maybe onto something here,
starting a new trend in "experimenting".
Marty RV-6A N826ME
Time: 02:02:03 PM PST US
From: Speedy11@aol.com
Subject: AeroElectric-List: Re: Transponder antenna signal
Great responses from everyone. I appreciate each one. Like Old Bob, I've
broken off stub antenna. I'd considered switching to a blade antenna, but
didn't want to fit a new antenna. I will reconsider that option, but I'd
like to investigate doing my own "antenna fairing."
I've been gradually making streamlining changes to my RV-8A and I now claim
the status of "world's fastest RV-8A." Maybe a streamlined transponder
antenna will help a tiny bit more. My new target is 200 KIAS in level
flight at 1000" MSL. I'm already within reach of that goal.
Thanks again for your responses.
Stan Sutterfield
Message 5
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: shielded 5 wire for trim servo |
Hi Bob
Thinking aloud here...
Wouldn't the noisy current of a brushed DC motor emit a heap of RF over long
wire runs (especially if the trim servo is locally grounded)?
Would that not be the reason for the shielding on the cable - not to stop
the servo from being interfered with, but to reduce the emitted noise?
Thanks
Etienne
On 17 January 2011 16:40, Robert L. Nuckolls, III <
nuckolls.bob@aeroelectric.com> wrote:
> nuckolls.bob@aeroelectric.com>
>
>
> At 11:28 AM 1/16/2011, you wrote:
>
>> I'm wiring my elevator trim servo and wondering what to do with the shield
>> on the 5 wire cable that came with my kit. The Ray Allen instructions say
>> nothing about it. Should I ground it at one or both ends, or just ignore it?
>> Thanks.
>> Jesse
>>
>
> Your choice. There is no value for having these
> wires shielded so what you do with the shield
> is optional and of no electrical significance.
>
> Bob . . .
>
>
Message 6
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: model airplane servo |
I'd add that, in my application, I have already done the hard over failure
analysis. My TigerCub is safely controllable with the trim tab at either
limit.
Bob Taylor
TigerCub N657RT
--------------------------------------------------
From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
Sent: Monday, January 17, 2011 9:41 AM
Subject: Re: AeroElectric-List: model airplane servo
> <nuckolls.bob@aeroelectric.com>
>
> At 12:48 PM 1/16/2011, you wrote:
>>I agree with Bob's comments on this. I get around this problem by early
>>testing to make sure that the "hard over failure" is easily controlled by
>>manual override.
>
> Good for you.
>
> Nothing can replace the value of doing failure modes
> effects analysis and/or demonstrations on a motor driven
> flight control surface. See:
>
> http://www.aeroelectric.com/articles/Trim_System_Failures.pdf
>
>
> Bob . . .
> ////
> (o o)
> ===========o00o=(_)=o00o========
> < Go ahead, make my day . . . >
> < show me where I'm wrong. >
> ================================
>
>
>
Message 7
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | shielded 5 wire for trim servo |
Thanks Bob=2C
In digging around on the Vans forum I saw mention that the Ray Allen trim i
ndicator could go bonkers while transmitting on a radio if the wire wasn't
shielded. I'm going to attempt to use the trim indicator on my Dynon screen
so hopefully it won't be a problem=2C but I soldered a 22 gauge wire onto
the shield at the servo end so I can run it into the fuselage just in case.
> Date: Mon=2C 17 Jan 2011 08:40:15 -0600
> To: aeroelectric-list@matronics.com
> From: nuckolls.bob@aeroelectric.com
> Subject: Re: AeroElectric-List: shielded 5 wire for trim servo
>
kolls.bob@aeroelectric.com>
>
> At 11:28 AM 1/16/2011=2C you wrote:
> >I'm wiring my elevator trim servo and wondering what to do with the
> >shield on the 5 wire cable that came with my kit. The Ray Allen
> >instructions say nothing about it. Should I ground it at one or both
> >ends=2C or just ignore it?
> >Thanks.
> >Jesse
>
> Your choice. There is no value for having these
> wires shielded so what you do with the shield
> is optional and of no electrical significance.
>
> Bob . . .
>
>
===========
===========
===========
===========
>
>
>
Message 8
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: model airplane servo |
It is amazing how many neat devices the "Nonman-carrying" quadrant of the flight
universe comes up with.
For those looking for more powerful servos and other neat devices, Google:
Robot Zone or Servo City.
Here's a great example: "the Magic Box" http://www.circuitcellar.com/psoc2002/winners/297.pdf It's hard not to want one of these. Complete info is back up a level.
I sell two distinctly different servo controllers: the EGPNMSC that drives Futaba
and other servos, and the TSCMR, that turns the MAC/RAC "sort-of-servo" into
a real servo. (Some glitch on my website is being worked on... so you might
not be able to see them now).
The Ray Allen trim box is really a nice piece of hardware. For those who want to
improve it a tiny bit, read the attached.
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones@charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=327300#327300
Attachments:
http://forums.matronics.com//files/tscmr_installation_manual_152.pdf
http://forums.matronics.com//files/egpnmsc_209.pdf
http://forums.matronics.com//files/rac_trim_and_trim_indicator_schematics_756.pdf
Message 9
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | shielded 5 wire for trim servo |
At 09:53 AM 1/17/2011, you wrote:
>Thanks Bob,
>In digging around on the Vans forum I saw mention that the Ray Allen
>trim indicator could go bonkers while transmitting on a radio if the
>wire wasn't shielded. I'm going to attempt to use the trim indicator
>on my Dynon screen so hopefully it won't be a problem, but I
>soldered a 22 gauge wire onto the shield at the servo end so I can
>run it into the fuselage just in case.
If that's the case, then the problem is in the indicator,
not the wiring. DO-160 qualification protocols for accessories
in TC aircraft do not generally allow a latent design
deficiency to be masked by user installed shielding,
filters, relocation, etc.
If you're wiring the actuator's potentiometer leads
to the inputs of some indicator OTHER than a Ray-Allen
product, then you've got a whole new ball game.
If you DO need the shielding, it should be connected
to ground as close as practical to the victim. I.e.
the indicator. Take the pigtail to a ground pin in
the connector.
Bob . . .
////
(o o)
===========o00o=(_)=o00o========
< Go ahead, make my day . . . >
< show me where I'm wrong. >
================================
Message 10
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: shielded 5 wire for trim servo |
At 09:42 AM 1/17/2011, you wrote:
>Hi Bob
>
>Thinking aloud here...
>
>Wouldn't the noisy current of a brushed DC motor emit a heap of RF
>over long wire runs (especially if the trim servo is locally grounded)?
Given that the actuator is a PM motor device with both
lead wires floating (to achieve CW/CCW operations) then
there's no 'local grounding' opportunities to be considered.
So all 5 wires from the actuator should be brought forward
with the motor pair splitting out to the trim command controls
and 3 position-pot wires going to the selected indicator.
Brushed DC motors DO emit noise. But it's a matter of
degree combined with the manner in which the noise
gets out of the system (radiated, conducted or both).
In this case, that tiny little motor (draws about 100 mA
as I recall) is a mouse roaring in a cacophony of
other noises. Further, the noise will come out conducted
on the twisted pair . . . these cannot radiate nor can
they become victims of radiation with respect to the
motor noise.
>Would that not be the reason for the shielding on the cable - not to
>stop the servo from being interfered with, but to reduce the emitted noise?
The actuator itself contains a motor and a pot. These
are not potential victims. The motor does generate
a modicum of insignificant noise. The pot generates
no noise.
If the Ray-Allen indicators have proven susceptible
to RF, it will be shown to have root cause in a common
mode conduction of RF into the indicator circuitry.
This MIGHT be improved upon by shielding, the common
wisdom seems to indicate this is the case. But it's
like carrying a fire extinguisher to offset the potential
effects of known fuel leaks. Better to fix the 'leak'
inside the indicator.
Bob . . .
////
(o o)
===========o00o=(_)=o00o========
< Go ahead, make my day . . . >
< show me where I'm wrong. >
================================
Message 11
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | shielding through DB9s |
I am keen to provide a shield through one end of a 4-wire cable to the other
(it's grounded only at one end and that will be preserved). The cable must
be cut to accommodate feed-through needs, so am using DB9s.*
Thing is, if I use metal-sprayed bodies, can I feed the wires
through the shield (as for a single wire) and then solder the shield to a
wire which is wound 'round one of the assembly bolts (#4x40)? This I hoped
would continue the shield through both DB9 bodies (bolt-body-body-bolt) and
onto the next section of shielded cable.
What say you?
Fair winds,
Ferg
Europa Classic mono 914
*The cable joins the Dynon D-100 EFIS to its attitude sensor
eight feet away and might be sensitive to nearby RF
Message 12
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | shielding through DB9s |
Ferg=3B
Simply carry the ground through one of the pins in the DB9. Don't worry abo
ut the cover. The unshielded portion within the cover is so tiny as to be i
nsignificant.
Bob McC
From: VE3LVO@rac.ca
Subject: AeroElectric-List: shielding through DB9s
I am keen to provide a shield through one end of a 4-wire cable to the othe
r (it=92s grounded only at one end and that will be preserved). The cable m
ust be cut to accommodate feed-through needs=2C so am using DB9s.*
Thing is=2C if I use metal-sprayed bodies=2C can I feed the wires t
hrough the shield (as for a single wire) and then solder the shield to a wi
re which is wound =91round one of the assembly bolts (#4x40)? This I hoped
would continue the shield through both DB9 bodies (bolt-body-body-bolt) and
onto the next section of shielded cable.
What say you?
Fair winds=2C
Ferg
Europa Classic mono 914
*The cable joins the Dynon D-100 EFIS to its attitude sensor eight feet awa
y and might be sensitive to nearby RF
Message 13
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: shielding through DB9s |
And use a solder sleeve to attach a pig-tail to the shield, and then the
pig tail to the pin. Steinair SS-3, under heatshrink.
Peter
On 17/01/2011 21:20, Bob McCallum wrote:
> Ferg;
>
> Simply carry the ground through one of the pins in the DB9. Don't
> worry about the cover. The unshielded portion within the cover is so
> tiny as to be insignificant.
>
> Bob McC
>
> ------------------------------------------------------------------------
> From: VE3LVO@rac.ca
> To: aeroelectric-list@matronics.com
> Subject: AeroElectric-List: shielding through DB9s
> Date: Mon, 17 Jan 2011 14:56:36 -0500
>
> I am keen to providea shield through one end of a 4-wire cableto the
> other (its grounded only at one end and that will be preserved). The
> cable must be cut toaccommodatefeed-through needs, so am using DB9s.*
>
> Thing is, if I use metal-sprayed bodies, can Ifeed the wires through
> the shield (as for a single wire) and then solder the shield to a
> wirewhich is woundround one of the assembly bolts (#4x40)? This I
> hoped would continue the shield through both DB9
> bodies(bolt-body-body-bolt)and onto the next section of shielded cable.
>
> What say you?
>
> Fair winds,
>
> Ferg
>
> Europa Classicmono 914
>
> *The cable joins the Dynon D-100 EFIS to its attitude
> sensor eight feet away and might be sensitive to nearby RF
>
> *
>
> -List" target=_blank>http://www.matronics.com/Navigator?AeroElectric-List
> ttp://forums.matronics.com
> =_blank>http://www.matronics.com/contribution
>
> *
> *
>
>
> *
Message 14
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Sandia txp/encoder combo any good? |
Does anyone have any thoughts on the new Sandia Aerospace transponder with
built in encoder?
I like the small size and integrated encoder, and the unit is attractively
priced (for a new unit).
Is there any general problems associated with encoders that make it
advisable to keep the encoder separate, so it can be replaced without replacing
the transponder?
Thanks for your thoughts. Skip Simpson
Message 15
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Sandia txp/encoder combo any good? |
Well, its only mode A/C, and a Trig TT-21 is $1870 from Spruce (less
elsewhere?) and provides Mode S. Apart from that looks good from the web
page. Will be interesting to see how it performs in the field.
http://www.sandia.aero/?q=node/66
Peter
On 17/01/2011 21:56, CardinalNSB@aol.com wrote:
> Does anyone have any thoughts on the new Sandia Aerospace transponder
> with built in encoder?
> I like the small size and integrated encoder, and the unit is
> attractively priced (for a new unit).
> Is there any general problems associated with encoders that make it
> advisable to keep the encoder separate, so it can be replaced without
> replacing the transponder?
> Thanks for your thoughts. Skip Simpson
> *
>
>
> *
Message 16
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | shielding through DB9s |
At 03:20 PM 1/17/2011, you wrote:
>Ferg;
>
>Simply carry the ground through one of the pins in the DB9. Don't
>worry about the cover. The unshielded portion within the cover is so
>tiny as to be insignificant.
>
Right on. I might add that there's no great transgression
for 'exposing' what might seem to be significant lengths
of the 'protected' wiring.
Shielding breaks electro-static coupling of noise that is
potentially significant if the victim wire shares a wire
bundle with a anatagnonist wire for considerable distance.
In a Beechjet were a pressure transducer wire might be
40' long and share a wire bundle with lots of butt-@#$@
noises, then the shielding has a high probability of
standing off a noise problem.
In our itty-bitty airplanes, wire runs are so short
that the probability of introducing noise issues for
lack of shielding is very low. I'll bet that 99.9% of
all shielded wires in small aircraft could be replaced
with unshielded, twisted pairs with no observable
adverse effects.
So make your shield transition at the connector look
nice even if it exposes what appears to be a lot of
wire.
See:
http://www.aeroelectric.com/articles/pigtail/pigtail.html
Solder sleeves are cool . . . and I do use them on
occasion but 'shade tree' shield terminations are
just as functional.
Bob . . .
////
(o o)
===========o00o=(_)=o00o========
< Go ahead, make my day . . . >
< show me where I'm wrong. >
================================
Message 17
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Sandia txp/encoder combo any good? |
Good Afternoon Skip,
The only comment I would make has to do with Sandia, the company.
Everything I have bought from them has been well built and has worked
flawlessly. I think the new product will likely be great.
Happy Skies,
Old Bob
In a message dated 1/17/2011 4:00:50 P.M. Central Standard Time,
CardinalNSB@aol.com writes:
Does anyone have any thoughts on the new Sandia Aerospace transponder with
built in encoder?
I like the small size and integrated encoder, and the unit is attractively
priced (for a new unit).
Is there any general problems associated with encoders that make it
advisable to keep the encoder separate, so it can be replaced without replacing
the transponder?
Thanks for your thoughts. Skip Simpson
(http://www.matronics.com/Navigator?AeroElectric-List)
(http://www.matronics.com/contribution)
Message 18
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | re: Shielding through DB9s |
Wow! What swift returns!
Many thanks for the suggestions on the above topic.
To Bob N: Sorry I missed the discussion on "articles/pigtail" and it of
course answered my question superbly. It also saves me a lot of fiddly-fooly
wirework. I am appreciative once more for the good offices on Matt Dralle's
net and Bob's Connections. Thanks too to Bob Mcc. way down the QEW, 50 cliks
from here.....!
Cheers
Ferg
Other Matronics Email List Services
These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.
-- Please support this service by making your Contribution today! --
|