Garmin Antenna placement

[Jim Rainer]

Herb, please post some pictures. Might help us all.

[gkey]

Originally Posted by Jim Rainer

Herb, please post some pictures. Might help us all.

AHA! I'n not alone in this, afterall...

There's a Chinese (I think) saying: When you ask the question, you may be a fool for a minute, but if you don't ask the question, you'll be a fool for life.

I will experiment with placements over the coming weekend, and report back. I have never subscribed to XM since I bought the unit almost a yeaqr ago, but I think it's high time.

I've got a 496 that works flawlessly in 2 airplanes but works intermittently in a third airplane. What I finally discovered after much angst and troubleshooting in the 3rd is that for some reason, when I have a certain nav frequency tuned in to either radio (Narcos)(109.7 -- my ILS freq at GMU), neither the GPS nor wx signal will activate.

Change the freq, and all is well within 5 minutes. Pete, you can explain this RFI (I assume)mystery to us common folk. It not only does this to my 496, but also does it to my Anywhere Map Wx PDA. So clearly, there's some sort of blocking of signals going on in the 3rd plane (TwinCo).

So, back to the original query, it may not be an antenna issue, but maybe a freq issue on a nav/com.

FWIW

Keven

P.S. Did I read somewhere that Larry sold his 337?
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Lovely Wendie

[stackj]

Keven,

There are some communication frequencies that interfere with GPS signals. I forget which harmonic it is, but it somehow seems to drive the GPS wild. There is a little item called a "notch filter" which goes in the communications radio antenna cable which will usually prevent this interference. IFR GPS systems have to be tested at each of the frequencies known to cause problems before they can be certified for IFR use. Sometimes the tank circuit in the output of certain ELTs will cause similiar problems. I think this only causes interference when transmitting on a comm radio.

Check with a good avionics shop. They should be able to resolve the issue.

Ever coming to Richmond? Does Peyton still speak to skymaster people?

http://www.aircraftspruce.com/catalo...s/tednotch.php

[gkey]

Kevin, I think you are right on the frequency issue. I did a search on Google "Garmin handheld no reception" and landed on a blog site, where someone wrote about the same thing. He stated that he contacted Garmin about the fact that his 396 would loose satellite reception out of the blue from time to time, and apparently they confirmed it was inteference with certain frequencies.

Get this: they sent him an "old" antenna (from the previous 196 series) and told him to try it. Apparently he does not have the problem anymore. Makes me wish I kept my 196...

I went to my plane yesterday to connect the antenna(s). I waited 30 minutes for the 396 to aquire satellites, and not a single one appeared on the screen. I took the handheld out, snapped on the little stub antenna and brought it home. I made it stand on the balcony railing were it had at least 270 degrees of clear view. Again it took about 20 minutes, but at last it aquired the satellites. I thought maybe it took that long because I had not used it for about 4 months, and it was setting up the whole calendar again from scratch. But, alas, I switched it off and on again, and waited another half hour before it would start getting the satellites. I can remember my 196 was as quick as lightning. Why is this unit so slow???

And I thought that I had found every way possible to spend money on an airplane . . . .

Well, I guess I'll be a couple hundred bucks poorer this week after buying a couple!

Jim, sorry to hear about the heart issues. As you may know, I had my own issues a few years back and was able to be back up in the air, so don't despair if you're not back up there yet.

Regarding Peyton, sometimes he'll stoop to the likes of me -- a 3-way twin driver, but is pretty preoccupied with his Cherokee 6 and his most recent acquisition -- a round engine, oil slobberin, aerobatic, deep gowlin, Yak. It sure is pretty, but as we like to kid about each time he lands at our airport, the fuel truck follows him from landing to his hangar!!!

kk
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Dc medical marijuana dispensary

[stackj]

Keven,

Be sure to check with your avionics guy (or gal) before buying a notch filter. That seems to be a likely solution, but your wiring may not have BNC connectors. Your avionics person may need to add or revise some connectors.

You can't just spend money on parts... You must buy labor too!

Don't despair... We just overhauled two props and the rear engine... now we are $42K poorer. At this point, we have invested about 220K in our 50K machine.

I'm sure the $ was a typo. Everyone who owns an airplane ends up making money on the acquisition and sale of the bird . . . at least that's what other folks/non-flying spouses hear!

Thanks for the reminder.

kk
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SabrinaCutie