XM Weather Blues

dekky111 · #1 04-19-2009, 10:25 AM

I'm having trouble receiving XM since my paint job. The unit is powered and showing a solid green LED.

Antenna is under the cowling on a shelf attached to the firewall. No trouble prior to paint. XM pinged the unit, but still no luck.

Could the paint (yellow non-metallic, 4 coats) be blocking the signal?

dekky111@gmail.com

DickDe · #2 04-19-2009, 12:00 PM

I placed my GPS antenna within my fiberglass wingtip & I called Garmin and asked if that was okay as far as signal reception. The answer was yes but the paint, especially if it has lead in it, "may" interfere with the signal. Mine works beautifully so obviously the paint I used is okay. Perhaps the same is true of XM signals.

Dick DeCramer
RV6 N500DD flying
RV8 Fuselage
Northfield, MN

Ironflight · #3 04-19-2009, 02:29 PM

Who's receiver (Garmin, GRT, etc), and what configuration. that will make a difference in the kind of advice you get. I always suspect anything that was working when it went in to a shop, and isn't working when it came out to be something the shop disconnected, changed, etc....

Paul

dekky111 · #4 04-19-2009, 07:06 PM

The XM is fed into a GRT Horizon I.

I will uncowl tomorrow and check the wiring. No obvious problem with wiring behind the panel.

GaryK · #5 04-19-2009, 07:28 PM

Jack,
Have you tried re-activating the weather? For some reason mine drops every 6 months or so. When you look at the configuration weather page it seems normal, reset it anyway.

www.xmradio.com/refresh/

Gary

Jamie · #6 04-19-2009, 08:31 PM

Quote:

Originally Posted by GaryK

Jack,
Have you tried re-activating the weather? For some reason mine drops every 6 months or so. When you look at the configuration weather page it seems normal, reset it anyway.

www.xmradio.com/refresh/

Gary

I'm assuming that's what he meant by XM pinging him, because there's really no way for XM to do a ping, per se. The XM units are receive only and XM has no idea if the unit is actually receiving a signal or not.

scard · #7 04-19-2009, 09:20 PM

Hmmm... Which GRT XM? How much time do you have on it before paint? If it is the serial fed with the "extra" GRT box on top, I was never able to get it anywhere stable either. Sometimes it would work, sometimes not (of course when you need it). I have talked to a couple others with the same experience. Bypassing the extra GRT XM serial box and only using the (same) WxWrox box into the GRT HX USB has been almost perfectly stable. Granted, that leaves only one of my three displays with weather... My suggestion, if you're using the GRT H1 XM serial interface, don't kill yourself over it. It just sucks.

dekky111 · #8 05-11-2009, 05:45 PM

Well the mystery is over. The problem turned out to be a bad connection of the USB between the processor and receiver. To fix it I pulled the cord out and replugged each end a few times, then fired it up. Works.
This brings up an issue of the USB connection that is not secured. Would not be a good thing if the connection broke in IFR when I'm trying to get weather.

beechrv9a · #9 09-07-2009, 06:39 AM

Left KLAF (Go Boilermakers!) VFR to return to 0W3 yesterday morning 1230Z. (KLAF-MIE-ROD-APE-KZZV-GRV-FDK-0W3). Weather briefing called for VFR along the route and the XM Weather was working properly upon departure. XM weather painted a great picture to avoid rainshowers coming up from the South around Muncie, Indiana. After fueling at Zanesville, Ohio I could not get XM weather to come up again on the 396. The antenna had been sitting in the sun for about an hour at this point. Although weather was no longer an issue, I was preturbed that it would not receive. The Garmin kept saying "waiting for DATA". I recycled the unit, but this did not help. This may have been discussed in a previous thread but I have not been able to find. Does heat affect the antenna? Or, is this a sign of an antenna going bad? After I got home and was sitting on the deck with a cold beverage, the 396 started receiving weather data again. The hockey puck was cooled down by this time. Or does XM periodically just quit relaying weather data?

Ironflight · #10 09-07-2009, 07:48 AM

Quote:

Originally Posted by beechrv9a

Left KLAF (Go Boilermakers!) VFR to return to 0W3 yesterday morning 1230Z. (KLAF-MIE-ROD-APE-KZZV-GRV-FDK-0W3). Weather briefing called for VFR along the route and the XM Weather was working properly upon departure. XM weather painted a great picture to avoid rainshowers coming up from the South around Muncie, Indiana. After fueling at Zanesville, Ohio I could not get XM weather to come up again on the 396. The antenna had been sitting in the sun for about an hour at this point. Although weather was no longer an issue, I was preturbed that it would not receive. The Garmin kept saying "waiting for DATA". I recycled the unit, but this did not help. This may have been discussed in a previous thread but I have not been able to find. Does heat affect the antenna? Or, is this a sign of an antenna going bad? After I got home and was sitting on the deck with a cold beverage, the 396 started receiving weather data again. The hockey puck was cooled down by this time. Or does XM periodically just quit relaying weather data?

My black XM hockey puck sits on my black glareshield down here in the Texas sun, and I have yet to have it fail due to temperatures - even when it reaches the point where you just can't touch anything! So as much as i like to blame heat for unknown performance problems (heat transfer being a dark art...), I'd put that low on the probability list.

The only time I have had a problem receiving XM is when my subscription had a minor hiccup that took 24 hours to sort out....(well, and then the Audio drops out on the downside of a loop of course....). I am wondering if you were getting "shadowing", with structure between your antenna and the satellites - not uncommon if you are flying north at higher latitudes. Just throwing that out there.

Paul