VOR Antenna location

How to keep the Cessna 170 flying and airworthy.

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GAHorn
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Re: VOR Antenna location

Post by GAHorn »

Silver French Grey was a Cessna interior color. The original Narco antenna I have is that color with black Narco lettering.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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bgiesbrecht
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Re: VOR Antenna location

Post by bgiesbrecht »

Looked all over the forums and also my logs and for the life of me, I can't find the p/n for the Narco NAV antenna (the "whiskers" version, mine is installed in the vert stab). Does anyone happen to have this P/N and whether or not it picks up glideslope? My radio is a Narco 12d+ (i.e. has GS capability, but I don't have a GS CDI).

I'm pulling the Narco soon and putting in a GNS430 (non-WAAS) but wondering if the Narco whiskers antenna will work with the NAV functionality.
Former owner of:
1953 170B
N1977C
s/n 26122
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GAHorn
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Re: VOR Antenna location

Post by GAHorn »

n3833v wrote:Just to stimulate thinking. Pointed forward could be a trash catcher such as anything flying from the cockpit, don't ask. Swept rearward any trash would fly off. ... John
OK, John... we’ve waited long-enough.... Whose bra was it?
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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DaveF
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Re: VOR Antenna location

Post by DaveF »

bgiesbrecht wrote:Looked all over the forums and also my logs and for the life of me, I can't find the p/n for the Narco NAV antenna (the "whiskers" version, mine is installed in the vert stab). Does anyone happen to have this P/N and whether or not it picks up glideslope? My radio is a Narco 12d+ (i.e. has GS capability, but I don't have a GS CDI).

I'm pulling the Narco soon and putting in a GNS430 (non-WAAS) but wondering if the Narco whiskers antenna will work with the NAV functionality.
All VHF nav antennas should work with any nav receiver, and they should all receive glideslope. Any problems will be caused by bad coax or balun attached to the antenna. But a quarter-wave dipole is the same antenna to any receiver.
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Bruce Fenstermacher
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Re: VOR Antenna location

Post by Bruce Fenstermacher »

As far as the VOR antenna pointing forward or backward, there is a technical difference in the performance level the antenna would give. This is because of the shape of the reception cone created as I understand it from my electrical engineer friends who specialize in antenna design and radio wave transmission. I can't remember which way would be technically better. In reality it probably doesn't matter based on the fact you see them mounted both ways. The expensive SR 20 and 22s and one Seneca III I can currently see in the hanger, all have them pointed backward and of course Narco's antenna most often found on the 170 was also backward if that is any indicator which way to point the whiskers.

BTW I connected a Garmin 155 GPS VOR receiver to the whiskers I mounted on the tail of my 170 and had no issues. Can't remember whether whiskers forward or back on that project but believe I went forward.
CAUTION - My forum posts may be worth what you paid for them!

Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
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bsdunek
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Re: VOR Antenna location

Post by bsdunek »

I have the Narco antenna on top of the cabin - been there since 1952. I did remove and refurbish it in the 80's. Works great.
Of course, I'm of the opinion that you can't improve on the 170 - mines an "A", and I try to keep it as original as practical. Love the key switches, round instruments, etc. Works for me.
Bruce
1950 170A N5559C
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DaveF
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Re: VOR Antenna location

Post by DaveF »

bgiesbrecht wrote:Looked all over the forums and also my logs and for the life of me, I can't find the p/n for the Narco NAV antenna (the "whiskers" version, mine is installed in the vert stab). Does anyone happen to have this P/N and whether or not it picks up glideslope? My radio is a Narco 12d+ (i.e. has GS capability, but I don't have a GS CDI).

I'm pulling the Narco soon and putting in a GNS430 (non-WAAS) but wondering if the Narco whiskers antenna will work with the NAV functionality.
Are you looking for a Narco mast antenna to install? If so, I’ve got one you can have. It’s just sitting in my hangar doing nothing. Yours if you want it.
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GAHorn
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Re: VOR Antenna location

Post by GAHorn »

Bruce Fenstermacher wrote:As far as the VOR antenna pointing forward or backward, there is a technical difference in the performance level the antenna would give. This is because of the shape of the reception cone created as I understand it from my electrical engineer friends who specialize in antenna design and radio wave transmission. I can't remember which way would be technically better. ....
If that is true, Bruce... should we always fly TOWARD the VOR? ......Or AWAY from it?

Should we keep it on our starboard side... or Port? :wink:

I would think the ground-plane would favor wherever the majority of the airplane’s structure would exist.... and if that were so... perhaps mfr’s should think about placing the antenna on the Nose... or the Tail... ? Or should they place it in the MIDDLE of the structure such as seen on old Connies, Douglass’s and Martins... or over the cabin on a 170.... Wonder why they didn’t just make those things shaped like an “X” instead of a “V”.... :wink:
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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bgiesbrecht
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Re: VOR Antenna location

Post by bgiesbrecht »

DaveF wrote:
bgiesbrecht wrote:Looked all over the forums and also my logs and for the life of me, I can't find the p/n for the Narco NAV antenna (the "whiskers" version, mine is installed in the vert stab). Does anyone happen to have this P/N and whether or not it picks up glideslope? My radio is a Narco 12d+ (i.e. has GS capability, but I don't have a GS CDI).

I'm pulling the Narco soon and putting in a GNS430 (non-WAAS) but wondering if the Narco whiskers antenna will work with the NAV functionality.
Are you looking for a Narco mast antenna to install? If so, I’ve got one you can have. It’s just sitting in my hangar doing nothing. Yours if you want it.
I appreciate that! Nope - I'm not looking for one - I have the whiskers already in the vert stab...but was curious about the p/n for it.
Former owner of:
1953 170B
N1977C
s/n 26122
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bgiesbrecht
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Re: VOR Antenna location

Post by bgiesbrecht »

gahorn wrote:
n3833v wrote:Just to stimulate thinking. Pointed forward could be a trash catcher such as anything flying from the cockpit, don't ask. Swept rearward any trash would fly off. ... John
OK, John... we’ve waited long-enough.... Whose bra was it?
haha!! :lol:
Former owner of:
1953 170B
N1977C
s/n 26122
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DaveF
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Re: VOR Antenna location

Post by DaveF »

It doesn't matter which way you point the antenna. The elements are angled toward each other to give the antenna an omnidirectional receive pattern. A standard dipole antenna has two elements lined up directly away from each other, which gives a donut-shaped receive pattern perpendicular to the wire axis. If the wires point outward, parallel to the airplane wings, the antenna has maximum reception along the fuselage axis and zero gain off to the sides. So they bend the elements toward each other, which munges the radiation pattern into a sorta-omni-circle.

Having said that, it sort of does matter which way you point the elements because the vertical fin interferes with the receive pattern. The less metal you put between the antenna elements, the better. But in reality we ignore that because there's plenty of energy available for good reception. I installed my VOR antenna facing forward to avoid injury because the pointy things are exactly at eye level.
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GAHorn
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Re: VOR Antenna location

Post by GAHorn »

My Baron originally had a “U” shaped mast-mounted antenna over the cockpit/pilot’s seats, exactly the same antenna as found on early airliners (see pic). It incorporated a glide-slope dipole mounted directly in front of the VOR radials. I’m sorry that I didn’t keep it for “posterity” or for my junk-pile-museum in the corner of my hangar.....but I decided to remove that in my remodeling and mimicked later Barons by installing whiskers on the vert-stab... in a forward/reverse. Still later, Beech used wrap-around towel-bars on the leading edge of the vertical, and then ultimately resorted to blades at the mid-chord position (which should thoroughly ignore the idea that “blanking” of any significance should be a concern.

Let’s face it, it’s VHF and the receive antenna has an incredible amount of “height” on top of a tower. MRA’s were/are published on Instrument charts to address anticipated reception issues and we’re pretty much (once again) measuring it with a micrometer, marking it with a grease-pencil, then cutting it with a hatchet. :lol:
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'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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AirMonte
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Re: VOR Antenna location

Post by AirMonte »

Hello Guys,
Can anyone recommend a “whisker” type VOR/LOC antenna for my ‘50 C170A ?
An install procedure ? I’m also wanting a GS antenna...what ideas you all have for that; I’ve heard of windshield mounted ones ? I’m going to install a king KX 125 w a Kn-75 GS receiver for this ...
Thanks
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cessna170bdriver
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Re: VOR Antenna location

Post by cessna170bdriver »

AirMonte wrote:Hello Guys,
Can anyone recommend a “whisker” type VOR/LOC antenna for my ‘50 C170A ?
An install procedure ? I’m also wanting a GS antenna...what ideas you all have for that; I’ve heard of windshield mounted ones ? I’m going to install a king KX 125 w a Kn-75 GS receiver for this ...
Thanks

I can’t recommend a brand of whisker antennas, as my airplane came with one and it has worked flawlessly since 1982. As for GS, you don’t need a separate antenna, just a splitter. I have a KX-155 with GS, and a panel jack for a handheld, all three fed by the whiskers mounted on top of the vertical stabilizer.
Miles

“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
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dstates
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Re: VOR Antenna location

Post by dstates »

AirMonte wrote:Hello Guys,
Can anyone recommend a “whisker” type VOR/LOC antenna for my ‘50 C170A ?
An install procedure ? I’m also wanting a GS antenna...what ideas you all have for that; I’ve heard of windshield mounted ones ? I’m going to install a king KX 125 w a Kn-75 GS receiver for this ...
Thanks

I recently installed a Rami AV-525. I chose it because it has an integral balan and you just connect the coax with a BNC connector. I had no interest in making my own balun.

You can get it from Aircraft Spruce. I also bought new coax (RG-400) from Aircraft Spruce and then was told you can get RG-400 from eBay a lot cheaper. Something to look into.
N1235D - 1951 170A - SN: 20118
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