 |
Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
|
| View previous topic :: View next topic |
| Author |
Message |
nuckolls.bob(at)aeroelect
Guest
|
 Posted: Fri Dec 28, 2012 10:01 am Post subject: RF interference on GRT fuel pressure |
 |
|
At 07:28 AM 12/28/2012, you wrote:
| Quote: | Tim,
I ordered four units (Their evaluation kit), so will start out by trying just the sensor DB. If that doesn’t solve the problem, I’ll add one to the TEMP sensor DB input. My fear is that the actual sensor (I have the high pressure precision unit for a fuel injected engine) is being effected by the RFI. If this is the case, the signal coming from the sensor would be bad, causing the EFIS alarms. This type of problem can only be solved by protecting the sensor with capacitors. |
I'm sorry to have been out of the loop on this.
Extended family holiday activities (still going
on) plus a run-in with the flu (grandkids attending
a constellation of schools are veritable dragnets
for viruses) has kept Dr. Dee and myself somewhat,
uh . . indisposed.
Is this a new, untried combination of hardware?
Is the problem common to other identical installations
or just with your airplane?
The great RFI/Filter/Ferrite/copper-box hat-dance
to mitigate an RFI issue may have more to do with
conditions outside the affected system.
Bring me up to date on what's happening, what you've
tried, etc.
Bob . . . [quote][b]
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
 |
tim2542(at)sbcglobal.net
Guest
|
| Posted: Fri Dec 28, 2012 12:30 pm Post subject: RF interference on GRT fuel pressure |
|
|
Hi Bob and thanks!
The issue is fuel pressure spikes on transmit with the GRT EIS system. At least 3 cases I know of. On mine it only occurs at the higher end of the band using either comm.
GRT suggested a split ferrite over the bundle just before it enters the DB 25 connector, I have not tried anything yet myself but plan to during my condition inspection.
These look like a slick way to do what you had suggested earlier, that is small caps between the pins and ground. My only concern is I know there are both gender DB 25 connectors on the back of the unit and I need to determine if they sell both and or which one I need.
Tim
Sent from my iPad
On Dec 28, 2012, at 10:00 AM, "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com (nuckolls.bob(at)aeroelectric.com)> wrote:
[quote] At 07:28 AM 12/28/2012, you wrote:
| Quote: | Tim,
I ordered four units (Their evaluation kit), so will start out by trying just the sensor DB. If that doesn’t solve the problem, I’ll add one to the TEMP sensor DB input. My fear is that the actual sensor (I have the high pressure precision unit for a fuel injected engine) is being effected by the RFI. If this is the case, the signal coming from the sensor would be bad, causing the EFIS alarms. This type of problem can only be solved by protecting the sensor with capacitors. |
I'm sorry to have been out of the loop on this.
Extended family holiday activities (still going
on) plus a run-in with the flu (grandkids attending
a constellation of schools are veritable dragnets
for viruses) has kept Dr. Dee and myself somewhat,
uh . . indisposed.
Is this a new, untried combination of hardware?
Is the problem common to other identical installations
or just with your airplane?
The great RFI/Filter/Ferrite/copper-box hat-dance
to mitigate an RFI issue may have more to do with
conditions outside the affected system.
Bring me up to date on what's happening, what you've
tried, etc.
Bob . . . | Quote: |
===================================
ctric.com
| Quote: | www.buildersbooks.com
uilthelp.com
|
matronics.com/contribution
===================================
st">http://www.matronics.com/Navigator?AeroElectric-List
===================================
cs.com
===================================
|
[b]
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
|
tomrv4(at)me.com
Guest
|
| Posted: Sat Dec 29, 2012 6:08 am Post subject: RF interference on GRT fuel pressure |
|
|
My turn...
My stand alone led low voltage warning light comes on every time I key the mic. My Dynon D180 shows no effect of keying the mic on the voltage read out. Suggestions on which direction I need go to solve?
Tom
On Dec 29, 2012, at 6:12 AM, bob noffs <icubob(at)gmail.com (icubob(at)gmail.com)> wrote:
| Quote: | hi all,
my led's on my trim display light up when i key the mike. also recently the warning light on my gr eis blinks but i didn't notice if a particular warning was displayed. light stops when i release the key. wonder if i am getting the same thing?
bob noffs
On Fri, Dec 28, 2012 at 2:28 PM, Tim Andres <tim2542(at)sbcglobal.net (tim2542(at)sbcglobal.net)> wrote:
| Quote: | Hi Bob and thanks!
The issue is fuel pressure spikes on transmit with the GRT EIS system. At least 3 cases I know of. On mine it only occurs at the higher end of the band using either comm.
GRT suggested a split ferrite over the bundle just before it enters the DB 25 connector, I have not tried anything yet myself but plan to during my condition inspection.
These look like a slick way to do what you had suggested earlier, that is small caps between the pins and ground. My only concern is I know there are both gender DB 25 connectors on the back of the unit and I need to determine if they sell both and or which one I need.
Tim
Sent from my iPad
On Dec 28, 2012, at 10:00 AM, "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com (nuckolls.bob(at)aeroelectric.com)> wrote:
| Quote: | At 07:28 AM 12/28/2012, you wrote:
| Quote: | Tim,
I ordered four units (Their evaluation kit), so will start out by trying just the sensor DB. If that doesn’t solve the problem, I’ll add one to the TEMP sensor DB input. My fear is that the actual sensor (I have the high pressure precision unit for a fuel injected engine) is being effected by the RFI. If this is the case, the signal coming from the sensor would be bad, causing the EFIS alarms. This type of problem can only be solved by protecting the sensor with capacitors. |
I'm sorry to have been out of the loop on this.
Extended family holiday activities (still going
on) plus a run-in with the flu (grandkids attending
a constellation of schools are veritable dragnets
for viruses) has kept Dr. Dee and myself somewhat,
uh . . indisposed.
Is this a new, untried combination of hardware?
Is the problem common to other identical installations
or just with your airplane?
The great RFI/Filter/Ferrite/copper-box hat-dance
to mitigate an RFI issue may have more to do with
conditions outside the affected system.
Bring me up to date on what's happening, what you've
tried, etc.
Bob . . .
|
===================================
ctric.com
| Quote: | www.buildersbooks.com
uilthelp.com
|
matronics.com/contribution
===================================
st">http://www.matronics.com/Navigator?AeroElectric-List
===================================
cs.com
===================================
|
|
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
|
bbradburry(at)bellsouth.n
Guest
|
| Posted: Sat Dec 29, 2012 6:22 am Post subject: RF interference on GRT fuel pressure |
|
|
Well if we are going to have a throwdown..
My rudder trim position indicator dims and goes to one end when I key the mike. The elevator trim position indicator right beside it is not affected.
RAC trim system, Garmin GNS430W radio.
Bill B
From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Tom Chapman
Sent: Saturday, December 29, 2012 9:07 AM
To: aeroelectric-list(at)matronics.com
Subject: Re: AeroElectric-List: Re: RF interference on GRT fuel pressure
My turn...
My stand alone led low voltage warning light comes on every time I key the mic. My Dynon D180 shows no effect of keying the mic on the voltage read out. Suggestions on which direction I need go to solve?
Tom
On Dec 29, 2012, at 6:12 AM, bob noffs <icubob(at)gmail.com (icubob(at)gmail.com)> wrote:
[quote]
hi all,
my led's on my trim display light up when i key the mike. also recently the warning light on my gr eis blinks but i didn't notice if a particular warning was displayed. light stops when i release the key. wonder if i am getting the same thing?
bob noffs
On Fri, Dec 28, 2012 at 2:28 PM, Tim Andres <tim2542(at)sbcglobal.net (tim2542(at)sbcglobal.net)> wrote:
Hi Bob and thanks!
The issue is fuel pressure spikes on transmit with the GRT EIS system. At least 3 cases I know of. On mine it only occurs at the higher end of the band using either comm.
GRT suggested a split ferrite over the bundle just before it enters the DB 25 connector, I have not tried anything yet myself but plan to during my condition inspection.
These look like a slick way to do what you had suggested earlier, that is small caps between the pins and ground. My only concern is I know there are both gender DB 25 connectors on the back of the unit and I need to determine if they sell both and or which one I need.
Tim
Sent from my iPad
On Dec 28, 2012, at 10:00 AM, "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com (nuckolls.bob(at)aeroelectric.com)> wrote:
| Quote: |
At 07:28 AM 12/28/2012, you wrote:
Tim,
I ordered four units (Their evaluation kit), so will start out by trying just the sensor DB. If that doesn’t solve the problem, I’ll add one to the TEMP sensor DB input. My fear is that the actual sensor (I have the high pressure precision unit for a fuel injected engine) is being effected by the RFI. If this is the case, the signal coming from the sensor would be bad, causing the EFIS alarms. This type of problem can only be solved by protecting the sensor with capacitors.
I'm sorry to have been out of the loop on this.
Extended family holiday activities (still going
on) plus a run-in with the flu (grandkids attending
a constellation of schools are veritable dragnets
for viruses) has kept Dr. Dee and myself somewhat,
uh . . indisposed.
Is this a new, untried combination of hardware?
Is the problem common to other identical installations
or just with your airplane?
The great RFI/Filter/Ferrite/copper-box hat-dance
to mitigate an RFI issue may have more to do with
conditions outside the affected system.
Bring me up to date on what's happening, what you've
tried, etc.
Bob . . .
012
|
345678901
2345678901234
[b]
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
|
Bob McC
Joined: 09 Jan 2006
Posts: 258
Location: Toronto, ON
|
| Posted: Sat Dec 29, 2012 6:25 am Post subject: RF interference on GRT fuel pressure |
|
|
Tim;
There is no issue with determining the “gender” of the suppression device. It has both a male and a female side and is inserted between the existing “plug” and “socket” therefore the same device does both “genders”. There is only one suppressor for each size DB connector (in your case presumably 25 pin) which works in all cases.
Bob McC
From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Tim Andres
Sent: Friday, December 28, 2012 3:29 PM
To: aeroelectric-list(at)matronics.com
Subject: Re: AeroElectric-List: Re: RF interference on GRT fuel pressure
Hi Bob and thanks!
The issue is fuel pressure spikes on transmit with the GRT EIS system. At least 3 cases I know of. On mine it only occurs at the higher end of the band using either comm.
GRT suggested a split ferrite over the bundle just before it enters the DB 25 connector, I have not tried anything yet myself but plan to during my condition inspection.
These look like a slick way to do what you had suggested earlier, that is small caps between the pins and ground. My only concern is I know there are both gender DB 25 connectors on the back of the unit and I need to determine if they sell both and or which one I need.
Tim
Sent from my iPad
On Dec 28, 2012, at 10:00 AM, "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com (nuckolls.bob(at)aeroelectric.com)> wrote:
| Quote: |
At 07:28 AM 12/28/2012, you wrote:
Tim,
I ordered four units (Their evaluation kit), so will start out by trying just the sensor DB. If that doesn’t solve the problem, I’ll add one to the TEMP sensor DB input. My fear is that the actual sensor (I have the high pressure precision unit for a fuel injected engine) is being effected by the RFI. If this is the case, the signal coming from the sensor would be bad, causing the EFIS alarms. This type of problem can only be solved by protecting the sensor with capacitors.
I'm sorry to have been out of the loop on this.
Extended family holiday activities (still going
on) plus a run-in with the flu (grandkids attending
a constellation of schools are veritable dragnets
for viruses) has kept Dr. Dee and myself somewhat,
uh . . indisposed.
Is this a new, untried combination of hardware?
Is the problem common to other identical installations
or just with your airplane?
The great RFI/Filter/Ferrite/copper-box hat-dance
to mitigate an RFI issue may have more to do with
conditions outside the affected system.
Bring me up to date on what's happening, what you've
tried, etc.
Bob . . . | Quote: | | ===================================ctric.com>www.buildersbooks.comuilthelp.commatronics.com/contribution===================================st">http://www.matronics.com/Navigator?AeroElectric-List=================================== |
012
|
3456789 | Quote: | | =================================== |
0 | Quote: | | =================================== |
1 | Quote: | | =================================== |
2 | Quote: | | =================================== |
3 | Quote: | | =================================== |
4 | Quote: | | =================================== |
5 | Quote: | | =================================== |
6 | Quote: | | =================================== |
7 | Quote: | | =================================== |
8 | Quote: | | =================================== |
90123456789 | Quote: | | >www.buildersbooks.com |
0 | Quote: | | >www.buildersbooks.com |
1 | Quote: | | >www.buildersbooks.com |
2
[quote][b]
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
_________________
Bob McC
Falco #908
(just starting) |
|
| Back to top |
|
|
tim2542(at)sbcglobal.net
Guest
|
| Posted: Sat Dec 29, 2012 8:16 am Post subject: RF interference on GRT fuel pressure |
|
|
Ok thanks Bob. I guess I had not thought it through...the thing is reversible!
Tim
Sent from my iPad
On Dec 29, 2012, at 6:24 AM, Bob McCallum <robert.mccallum2(at)sympatico.ca (robert.mccallum2(at)sympatico.ca)> wrote:
[quote] v\:* {behavior:url(#default#VML);} o\:* {behavior:url(#default#VML);} w\:* {behavior:url(#default#VML);} .shape {behavior:url(#default#VML);} <![endif]--> st1\:*{behavior:url(#default#ieooui) } <![endif]-->
Tim;
There is no issue with determining the “gender” of the suppression device. It has both a male and a female side and is inserted between the existing “plug” and “socket” therefore the same device does both “genders”. There is only one suppressor for each size DB connector (in your case presumably 25 pin) which works in all cases.
Bob McC
From: owner-aeroelectric-list-server(at)matronics.com (owner-aeroelectric-list-server(at)matronics.com) [mailto:owner-aeroelectric-list-server(at)matronics.com (owner-aeroelectric-list-server(at)matronics.com)] On Behalf Of Tim Andres
Sent: Friday, December 28, 2012 3:29 PM
To: aeroelectric-list(at)matronics.com (aeroelectric-list(at)matronics.com)
Subject: Re: AeroElectric-List: Re: RF interference on GRT fuel pressure
Hi Bob and thanks!
The issue is fuel pressure spikes on transmit with the GRT EIS system. At least 3 cases I know of. On mine it only occurs at the higher end of the band using either comm.
GRT suggested a split ferrite over the bundle just before it enters the DB 25 connector, I have not tried anything yet myself but plan to during my condition inspection.
These look like a slick way to do what you had suggested earlier, that is small caps between the pins and ground. My only concern is I know there are both gender DB 25 connectors on the back of the unit and I need to determine if they sell both and or which one I need.
Tim
Sent from my iPad
On Dec 28, 2012, at 10:00 AM, "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com (nuckolls.bob(at)aeroelectric.com)> wrote:
| Quote: |
At 07:28 AM 12/28/2012, you wrote:
Tim,
I ordered four units (Their evaluation kit), so will start out by trying just the sensor DB. If that doesn’t solve the problem, I’ll add one to the TEMP sensor DB input. My fear is that the actual sensor (I have the high pressure precision unit for a fuel injected engine) is being effected by the RFI. If this is the case, the signal coming from the sensor would be bad, causing the EFIS alarms. This type of problem can only be solved by protecting the sensor with capacitors.
I'm sorry to have been out of the loop on this.
Extended family holiday activities (still going
on) plus a run-in with the flu (grandkids attending
a constellation of schools are veritable dragnets
for viruses) has kept Dr. Dee and myself somewhat,
uh . . indisposed.
Is this a new, untried combination of hardware?
Is the problem common to other identical installations
or just with your airplane?
The great RFI/Filter/Ferrite/copper-box hat-dance
to mitigate an RFI issue may have more to do with
conditions outside the affected system.
Bring me up to date on what's happening, what you've
tried, etc.
Bob . . . 012
|
3456789 | Quote: | | =================================== |
0 | Quote: | | =================================== |
1 | Quote: | | =================================== |
2 | Quote: | | =================================== |
3 | Quote: | | =================================== |
4 | Quote: | | =================================== |
5 | Quote: | | =================================== |
6 | Quote: | | =================================== |
7 | Quote: | | =================================== |
8
| Quote: | | =================================== |
9
[b]
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
|
nuckolls.bob(at)aeroelect
Guest
|
| Posted: Sat Dec 29, 2012 10:12 am Post subject: RF interference on GRT fuel pressure |
|
|
At 08:24 AM 12/29/2012, you wrote:
| Quote: | Tim;
There is no issue with determining the “gender” of the suppression device. It has both a male and a female side and is inserted between the existing “plug” and “socket” therefore the same device does both “genders”. There is only one suppressor for each size DB connector (in your case presumably 25 pin) which works in all cases. |
I would expand on Bob's comments to remind
readers that the designers of 'universal'
suppression connectors cannot know which,
if any, pins within the array are at RF
ground. Hence, they MUST assume that all
pins are 'hot' and worthy of protection.
This means that the connector SHELL is expected
to become RF ground for all filters built
into the device.
When I add capacitors to the connector of
a unique 'victim', I am knowing which pins
are suitable for grounding the capacitors.
I can also focus on one or perhaps a few pins
that may be vulnerable . . . i.e. not all
pins get caps.
So when using a universal 'filtered' connector,
make sure your connector's shell gets into a
close relationship with RF ground for the
device you're trying to protect.
Bob . . . [quote][b]
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
|
nuckolls.bob(at)aeroelect
Guest
|
| Posted: Sat Dec 29, 2012 10:14 am Post subject: RF interference on GRT fuel pressure |
|
|
At 08:21 AM 12/29/2012, you wrote:
| Quote: | Well if we are going to have a throwdown..
My rudder trim position indicator dims and goes to one end when I key the mike. The elevator trim position indicator right beside it is not affected.
RAC trim system, Garmin GNS430W radio. |
The RAC trim indicators have always been
very vulnerable to ordinary levels of RF
in the cockpit. I spoke with the folks at
OSH many years ago offering to assist in
getting their products RF hardened but they
weren't interested.
Most folks know that it happens and simply
ignores it . . .
Bob . . . [quote][b]
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
|
bbradburry(at)bellsouth.n
Guest
|
| Posted: Sat Dec 29, 2012 3:02 pm Post subject: RF interference on GRT fuel pressure |
|
|
Thanks, Bob. That is exactly what I will do.
I called and spoke with someone at RAC about this problem. His response was “Well it works ok except when you transmit doesn’t it?” I suspected then that good enough was good enough.
Bill B
From: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] On Behalf Of Robert L. Nuckolls, III
Sent: Saturday, December 29, 2012 1:14 PM
To: aeroelectric-list(at)matronics.com
Subject: RE: AeroElectric-List: Re: RF interference on GRT fuel pressure
At 08:21 AM 12/29/2012, you wrote:
Well if we are going to have a throwdown..
My rudder trim position indicator dims and goes to one end when I key the mike. The elevator trim position indicator right beside it is not affected.
RAC trim system, Garmin GNS430W radio.
The RAC trim indicators have always been
very vulnerable to ordinary levels of RF
in the cockpit. I spoke with the folks at
OSH many years ago offering to assist in
getting their products RF hardened but they
weren't interested.
Most folks know that it happens and simply
ignores it . . .
Bob . . . 01234567890123456789
[quote][b]
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
|
erich.weaver(at)urs.com
Guest
|
| Posted: Sun Dec 30, 2012 2:55 am Post subject: RF interference on GRT fuel pressure |
|
|
Hate to be discouraging, but I have this same problem and have previously tried the dsub filter technique on both the EFIS and on the EIS with zero success. Just living with a few seconds of flashing warning light on the EFIS now. Let us know if anyone fares any better.
Erich
This e-mail and any attachments contain URS Corporation confidential information that may be proprietary or privileged. If you receive this message in error or are not the intended recipient, you should not retain, distribute, disclose or use any of this information and you should destroy the e-mail and any attachments or copies.
| | - The Matronics AeroElectric-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?AeroElectric-List |
|
|
|
| Back to top |
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
