ADF Removal

How to keep the Cessna 170 flying and airworthy.

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Onewinglo
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ADF Removal

Post by Onewinglo »

Guys,
I plan to remove the ADF radio pictured below during the annual in October. Are both of these antenna on the belly associated with the ADF radio?
Thanks, JP
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C170A N1714D
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lowNslow
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Re: ADF Removal

Post by lowNslow »

The front antenna (blade) is a marker beacon antenna, the rear one is probably your ADF antenna.
Karl
'53 170B N3158B SN:25400
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jmurtap
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Re: ADF Removal

Post by jmurtap »

I just removed mine, it had the square one on the bottom like yours and a cloths hanger that ran the length of the fuse on top. If coarse now I day dream about what goodies can go in that spot empty space.
Jason P
53 170
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Onewinglo
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Re: ADF Removal

Post by Onewinglo »

lowNslow wrote:The front antenna (blade) is a marker beacon antenna, the rear one is probably your ADF antenna.
I dont have a marker beacon so I guess we will remove both antenna when the radio comes out.
Thanks Karl and Jason.
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lowNslow
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Re: ADF Removal

Post by lowNslow »

Your marker beacon is the "O" "M" and "I" indicator lights on the left side of your audio panel.
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DaveF
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Re: ADF Removal

Post by DaveF »

lowNslow wrote:Your marker beacon is the "O" "M" and "I" indicator lights on the left side of your audio panel.
Press the "MKR" button on your audio panel and listen for the beeping next time you fly to an ILS-equipped runway.
Onewinglo
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Re: ADF Removal

Post by Onewinglo »

DaveF wrote:
lowNslow wrote:Your marker beacon is the "O" "M" and "I" indicator lights on the left side of your audio panel.
Press the "MKR" button on your audio panel and listen for the beeping next time you fly to an ILS-equipped runway.
So I do have a marker beacon. :oops:
Now I questioon if I should leave the beacon antenna in place... Is a marker beacon still widely used for the IFR guys?
JP
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DaveF
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Re: ADF Removal

Post by DaveF »

Definitely leave it. Marker beacons are slowly being phased out, but they're used on most ILS-equipped runways. I wish I had one. There's really nothing to be gained by removing the antenna and cable, which weigh almost nothing, and you won't have to fill the holes.
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cessna170bdriver
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Re: ADF Removal

Post by cessna170bdriver »

I'd leave the ADF if it's working, but I wouldn't pay to have it repaired if it wasn't. Not a popular point of view but it's mine...
Miles

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N2625U
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Re: ADF Removal

Post by N2625U »

When I bought my 172 about 12 years ago I had an ADF but only the radio worked, not the needle. After about 3 years figured out I hadn't used it during that time so when installed new radios had it removed. Sometimes I think they pulled 20 pounds of wiring out...
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cessna170bdriver
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Re: ADF Removal

Post by cessna170bdriver »

When I lived in Mississippi, the flight back to visit family in NW Georgia was just about long enough to listen to a Braves game on WSB, a clear channel AM station out of Atlanta, and the needle reminded me that I was headed in roughly the right direction. 8) It now takes both XM and GPS accomplish those things. Time marches on...
Miles

“I envy no man that knows more than myself, but pity them that know less.”
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hilltop170
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Re: ADF Removal

Post by hilltop170 »

I regularly listen to AM radio in the 170 on the ADF. On long cross countrys there is usually not a lot to do and searching for a good local station with the farm and ranch report or listening to music is always a good pastime. The GPS system does go down from time to time but it would be tough to shut down all the NDBs that are left and all of the AM radio stations. It is still good back-up unless the space is needed for new radios.

The entire KR-86 installation weighs less than 10lb including wires so its not a big factor and I would definitely leave the marker beacon in place. You might want to get your instrument rating some day and it will come in handy.
Last edited by hilltop170 on Fri Sep 04, 2015 12:26 am, edited 1 time in total.
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Onewinglo
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Re: ADF Removal

Post by Onewinglo »

Thanks for the feedback guys. I plan to attend a flap jack fly-in Saturday and the airport has an NDB so Ill test my ADF. Plus we have a clear channel AM station in New Orleans (WWL) which the fish spotters over the Gulf used for decades. ADF was popular with those guys because they flew to low for VOR.
JP
C170A N1714D
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