Vertical Card Compass Interference?

[Curt Lewis - 95]

Vertical Card Compass Interference?

I'm installing an LXNAV S100 top center in my panel with FLARM, ADS-B and GPS antennas at back/top of instrument shroud. I have a PAI-700 Vertical Card Compass mounted now on top of shroud about 2/3 back from front. As it sits now it would be only ~4" from antennas at rear. If you go by manufacturers' recommendations on anything electrical everything should be at least 3 feet from everything else :).

1 - Does anyone have any empirical evidence of antenna interference specifically from this type of compass?

I could move the compass forward but it gets closer to the S100.

2 - Does anyone have any empirical evidence of Vario/Flight Computer interference from this type of compass?

Note: I am less concerned about the effect on the compass vs the compass effect on the other stuff :)

Thanks all.

Curt - 95

[[email protected]]

On Thursday, May 16, 2019 at 10:46:29 AM UTC-4, Curt Lewis - 95 wrote:
> Vertical Card Compass Interference?
>
> I'm installing an LXNAV S100 top center in my panel with FLARM, ADS-B and GPS antennas at back/top of instrument shroud. I have a PAI-700 Vertical Card Compass mounted now on top of shroud about 2/3 back from front. As it sits now it would be only ~4" from antennas at rear. If you go by manufacturers' recommendations on anything electrical everything should be at least 3 feet from everything else :).
>
> 1 - Does anyone have any empirical evidence of antenna interference specifically from this type of compass?
>
> I could move the compass forward but it gets closer to the S100.
>
> 2 - Does anyone have any empirical evidence of Vario/Flight Computer interference from this type of compass?
>
> Note: I am less concerned about the effect on the compass vs the compass effect on the other stuff :)
>
> Thanks all.
>
> Curt - 95

That compass is not an electronic device. It's just a swiveling magnet. Won't affect anything else.

[MNLou]

It is highly possible that the S100 (or other speakers) will interfere with the PAI compass.

I'm trying to figure out that gremlin right now. PAI recommended shielding the speakers which I am working on.

YMMV -

Lou

[[email protected]]

On Friday, May 17, 2019 at 7:05:48 PM UTC-4, MNLou wrote:
> It is highly possible that the S100 (or other speakers) will interfere with the PAI compass.
>
> I'm trying to figure out that gremlin right now. PAI recommended shielding the speakers which I am working on.
>
> YMMV -
>
> Lou

It is difficult to "shield" the field of a permanent magnet. A conductive layer, such as aluminum, shields against electromagnetic fields, not this. Best thing to do is to mount the speaker (which has a strong magnet in it) far away from the compass (at least a foot, preferably two). But check the compass behavior first, maybe it's OK as it is. At least the speaker's field does not change. Just check the compass reading in all directions.

[bumper[_4_]]

On Friday, May 17, 2019 at 4:05:48 PM UTC-7, MNLou wrote:
> It is highly possible that the S100 (or other speakers) will interfere with the PAI compass.
>
> I'm trying to figure out that gremlin right now. PAI recommended shielding the speakers which I am working on.
>
> YMMV -
>
> Lou

If the interfering magnetic field is strong enough, the correction adjustments in the compass won't be able to compensate for the stray field. What you then do is set the correction adjustments on the compass back to neutral. Then use a separate neodymium magnet to correct the compass error instead of the compass built in magnets.

Start to swing the compass as you would normally do, but move the strong neodymium magnet around near the front of the panel. Rotate it and change the distance as required to determine what location will best correct the compass error. When you have it as good as possible, tape the magnet in position on the backside of the panel.

Repeat the compass swinging procedure using the compass built in correction magnets. This should get you acceptably close. Permanently attach additional correction magnet in place.

bumper

[Jonathan St. Cloud]

On Thursday, May 16, 2019 at 11:18:36 AM UTC-7, wrote:
> On Thursday, May 16, 2019 at 10:46:29 AM UTC-4, Curt Lewis - 95 wrote:
> > Vertical Card Compass Interference?
> >
> > I'm installing an LXNAV S100 top center in my panel with FLARM, ADS-B and GPS antennas at back/top of instrument shroud. I have a PAI-700 Vertical Card Compass mounted now on top of shroud about 2/3 back from front. As it sits now it would be only ~4" from antennas at rear. If you go by manufacturers' recommendations on anything electrical everything should be at least 3 feet from everything else :).
> >
> > 1 - Does anyone have any empirical evidence of antenna interference specifically from this type of compass?
> >
> > I could move the compass forward but it gets closer to the S100.
> >
> > 2 - Does anyone have any empirical evidence of Vario/Flight Computer interference from this type of compass?
> >
> > Note: I am less concerned about the effect on the compass vs the compass effect on the other stuff :)
> >
> > Thanks all.
> >
> > Curt - 95
>
> That compass is not an electronic device. It's just a swiveling magnet. Won't affect anything else.

Just curious, how many of you actually use a compass? I flying the mountains not flat land, but the only time I can remember referencing a compass was a vertical card to see the runway direction. I have two flux compasses in instruments and I tried to license the glider without, but one minimum equipment list.

[Dan Marotta]

Compass?Â* What's that?

On 5/18/2019 7:57 AM, Jonathan St. Cloud wrote:
> On Thursday, May 16, 2019 at 11:18:36 AM UTC-7, wrote:
>> On Thursday, May 16, 2019 at 10:46:29 AM UTC-4, Curt Lewis - 95 wrote:
>>> Vertical Card Compass Interference?
>>>
>>> I'm installing an LXNAV S100 top center in my panel with FLARM, ADS-B and GPS antennas at back/top of instrument shroud. I have a PAI-700 Vertical Card Compass mounted now on top of shroud about 2/3 back from front. As it sits now it would be only ~4" from antennas at rear. If you go by manufacturers' recommendations on anything electrical everything should be at least 3 feet from everything else :).
>>>
>>> 1 - Does anyone have any empirical evidence of antenna interference specifically from this type of compass?
>>>
>>> I could move the compass forward but it gets closer to the S100.
>>>
>>> 2 - Does anyone have any empirical evidence of Vario/Flight Computer interference from this type of compass?
>>>
>>> Note: I am less concerned about the effect on the compass vs the compass effect on the other stuff :)
>>>
>>> Thanks all.
>>>
>>> Curt - 95
>> That compass is not an electronic device. It's just a swiveling magnet. Won't affect anything else.
> Just curious, how many of you actually use a compass? I flying the mountains not flat land, but the only time I can remember referencing a compass was a vertical card to see the runway direction. I have two flux compasses in instruments and I tried to license the glider without, but one minimum equipment list.

--
Dan, 5J

[JS[_5_]]

On Saturday, May 18, 2019 at 8:32:38 AM UTC-7, Dan Marotta wrote:
> Compass?Â* What's that?
> Dan, 5J

Reference standard for innacurate instruments.
Jim

[[email protected]]

my MEL does not reference a compass, but the factory does. ASW27 early model ser 31 Standard certification. I removed it and my AP/IA doesnt have an issue with it.

[SoaringXCellence]

On Saturday, May 18, 2019 at 2:11:39 PM UTC-7, wrote:
> my MEL does not reference a compass, but the factory does. ASW27 early model ser 31 Standard certification. I removed it and my AP/IA doesnt have an issue with it.

The operating manual for three gliders I've owned state that a compass is only needed for cloud flying.

[Charles Longley]

Pretty sure you don’t need a compass in the US. Reality is if it’s a concern try the glider in various directions on the ground with the radios on and off. I don’t see it as a real problem flying gliders.