GNS 530 and VOR ID

Matthew

Touchdown! Greaser!
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Matthew
Tuning in a VOR on the 530 gets me the VOR identifier, radial, and distance in the VLOC ident window.

I haven't been able to find this answer: Does the 530 listen to the Morse, then decode it and display it? Or is it using some database instead and just looking up the freq that's been dialed in?
 
I've never known the 430/530 to have a morse reader built-in.

You really should be listening to it, and verifying the function/status of the station before depending on it.
 
Screen Shot 2022-11-04 at 3.26.32 PM.jpg

I assume from this it's decoding the Morse as broadcast from the station. My 172N had a Davtron gadget that spelled out the identifier of whatever station the navcom was receiving. Very handy.
 
It listens to the morse code. The manual says:
> When the GNS 530 is tuned to a nearby VOR, the VLOC Ident Window (Figure 9-3) displays the Morse code identifier of the selected station

I wish the 430 did that.
 
It listens to the morse code. The manual says:
> When the GNS 530 is tuned to a nearby VOR, the VLOC Ident Window (Figure 9-3) displays the Morse code identifier of the selected station

I wish the 430 did that.

I'm not trying to nit-pick (really): but there's a difference between "displays the Morse code identifier", and "displays the Morse code sent by the station."

The first can be done by a geo-aware database. The second requires a morse reader.
 
I'm not trying to nit-pick (really): but there's a difference between "displays the Morse code identifier", and "displays the Morse code sent by the station."

The first can be done by a geo-aware database. The second requires a morse reader.
Yes, the GNS530 wording is unfortunate. The GNS480, SL30, GNC255 and GTN650/750 manuals specifically say that they decode the Morse.

I suppose one experiment would be to listen to the Morse and then see if the GNS530 waits until after its sent before displaying the identifier.
 
One way to test it would be, to tune to the station, and see how long it takes for the station identifier to display in the window.

If it happens immediately, this indicates that it's most likely a database.

If it takes 5-20 seconds, then it's possibly listening to and decoding the Morse.
 
One way to test it would be, to tune to the station, and see how long it takes for the station identifier to display in the window.

Tune a station 300nm away and see what, if any, identifier displays.
 
It is way more likely that it is pulled from the database but @Rgbeard suggested a good way to determine what it is doing.
 
It's pretty slow Morse, at a consistent speed and pitch, so it's not like it would be a particularly challenging task technologically.
 
It is way more likely that it is pulled from the database but @Rgbeard suggested a good way to determine what it is doing.
The database would have to know approximately where the plane was in order to distinguish between VORs on the same frequency. It seems to me that Garnin would want VOR identification to work even if the GPS didn't, such as when military interference testing is going on. Especially then.
 
Tuning in a VOR on the 530 gets me the VOR identifier, radial, and distance in the VLOC ident window.

I haven't been able to find this answer: Does the 530 listen to the Morse, then decode it and display it? Or is it using some database instead and just looking up the freq that's been dialed in?
The 530 makes a positive identification of station reception by decoding the identifier. That photo from the Pilot Guide @Pilawt posted? When you see the ID, radial and distance displayed in the lower window, the station has been decoded and positively identified. As the AIM puts it,

Some VOR equipment decodes the identifier and displays it to the pilot for verification to charts, while other equipment simply displays the expected identifier from a database to aid in verification to the audio tones. You should be familiar with your equipment and use it appropriately. If your equipment automatically decodes the identifier, it is not necessary to listen to the audio identification
I suppose one experiment would be to listen to the Morse and then see if the GNS530 waits until after its sent before displaying the identifier
That what it does. You see that regularly with localizers since you have to be within its angular reception window. You tune it when you set up for the approach but the ID doesn't show up in the lower window until it is positively identified.
 
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It's handier to simply be proficient in Morse. :p

Handy, but not exactly easiest. :D

When I was studying Morse for my 13 WPM ham test, I noticed I did not need to look a the chart for the Morse, I could mentally decode it.
 
I know I’ve flown systems that actually identify, but always wondered if it was decoding the Morse or if there was some other info modulated onto the carrier. That would make an ID nearly instant.

On many transport category EFIS systems, once you saw the station ID window populate with the identifier, that was considered “IDed”. And it happened fast.
 
Personally, I still don’t see enough direct evidence from anything authoritative to believe one way or the other how this works. I’m acknowledging the photo that was posted by @Pilawt. However, as it is worded, it says that the Garmin displays the Morse code identifier. Gosh, so does my old paper chart from 1976, and it didn’t decode anything.

If I was the OP, I’d like someone to either test the morse-to-ID and report back, or post something well-enough worded to be clear, from an authoritative source. Then we can put this to bed.
 
It can't do it with a database because the same ILS frequency is used with different identifiers at the same airport. For example, at IAD 110.1 sends I-IAD when 1R is in use, but I-SGC when 19L is in use.
 
Personally, I still don’t see enough direct evidence from anything authoritative to believe one way or the other how this works. I’m acknowledging the photo that was posted by @Pilawt. However, as it is worded, it says that the Garmin displays the Morse code identifier. Gosh, so does my old paper chart from 1976, and it didn’t decode anything.

If I was the OP, I’d like someone to either test the morse-to-ID and report back, or post something well-enough worded to be clear, from an authoritative source. Then we can put this to bed.
Since I've flow IFR with one for decades, we don't share the same concerns.
 
It is way more likely that it is pulled from the database but @Rgbeard suggested a good way to determine what it is doing.
Every other radio with a VLOC component in Garmin's catalog says in its respective manual that it decodes the Morse. It would be weird for the GNS530 to be the lone oddball.
 
On one of my flights with a 430, the owner had apparently pulled the database chip to update it, because the unit reported that it had no navigation database. So one way to test it would be to pull the chip and see if the unit still displays navaid IDs.
 
Since I've flow IFR with one for decades, we don't share the same concerns.

I don’t have the same advantage as you in this case and base my position on the tangible information.

This in no way means your significant experience is devalued by me. Knowing this and all else posted here makes it far more likely to be so. However, I will say, in the case of this one device, Garmin screwed the pooch on describing how their system functions, leaving the window open for doubt.
 
Is the same ambiguity in the 430 manual?
 
The purpose of verifying the morse code identifier is to ensure the station is online and not in test mode. Why would a nav radio look up an identifier from a database (which would be near impossible as Ron noted above) if you still had to audibly verify the Morse code transmission?

A agree the Garmin manual could have been a bit more explicit in explaining what it's doing.
 
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The purpose of verifying the morse code identifier is to ensure the station is online and not in test mode. Why would a nav radio look up an identifier from a database (which would be near impossible as Ron noted above) if you still had to audibly verify the Morse code transmission.

A agree the Garmin manual could have been a bit more explicit in explaining what it's doing.

My Garmin Nav/Comm GNC-255A is an example of such. It has a database, which I update regularly, and shows the ID of the stations as I dial past their frequencies. It’s geo-referenced getting position information from my Garmin 375 GPS.
 
My Garmin Nav/Comm GNC-255A is an example of such. It has a database, which I update regularly, and shows the ID of the stations as I dial past their frequencies. It’s geo-referenced getting position information from my Garmin 375 GPS.
In the GNC 255A/255B manual, Section 1.1, it says, "the GNC 255 also incorporates workload-reducing functions such as automatic decoding of the Morse code station
identifier for VOR/LOC...."
 
My Garmin Nav/Comm GNC-255A is an example of such. It has a database, which I update regularly, and shows the ID of the stations as I dial past their frequencies. It’s geo-referenced getting position information from my Garmin 375 GPS.

From the Garmin website re: The GNC 255:

"The device even automatically decodes a station’s Morse code to provide a positive identification – no aural decoding required."


I've taken numerous part 135 checkrides in Garmin equipped aircraft. The check airmen (and FAA) have always been happy with using the Garmin to id a station, VOR or LOC.
 
In the GNC 255A/255B manual, Section 1.1, it says, "the GNC 255 also incorporates workload-reducing functions such as automatic decoding of the Morse code station
identifier for VOR/LOC...."

while this may be true, it’s also showing the station IDs as I whiz by them turning dials. There’s certainly no active Morse listening happening to enable that.
 
This airplane also has a GNC255 Nav/Comm. Reading that manual has some interesting findings.

When dialing in a freq into standby, the unit will display the NEAREST facility with that matching frequency using a reverse lookup. It specifically says: "CAUTION: THE IDENTIFIER IS DETERMINED FROM THE DATABASE AND IS NOT THE DECODED NAV IDENTIFIER."

But, when you flip it into the active and go into OBS mode, it does listen and decode the Morse: "NOTE: The Identifier is the decoded NAV identifier from the Morse code broadcast by the station."
 
This airplane also has a GNC255 Nav/Comm. Reading that manual has some interesting findings.

When dialing in a freq into standby, the unit will display the NEAREST facility with that matching frequency using a reverse lookup. It specifically says: "CAUTION: THE IDENTIFIER IS DETERMINED FROM THE DATABASE AND IS NOT THE DECODED NAV IDENTIFIER."

But, when you flip it into the active and go into OBS mode, it does listen and decode the Morse: "NOTE: The Identifier is the decoded NAV identifier from the Morse code broadcast by the station."

This is great information. I’m really pleased at what I’m getting from this thread.

Previously, I have paid no attention to this as I am proficient in Morse.
 
Is the same ambiguity in the 430 manual?
No. The 430 doesn't have the real estate to display the extra box like the 530. The 430 Pilot Guide (or AFMS) doesn't discuss decoding the ID at all.
 
I don’t have the same advantage as you in this case and base my position on the tangible information.

This in no way means your significant experience is devalued by me. Knowing this and all else posted here makes it far more likely to be so. However, I will say, in the case of this one device, Garmin screwed the pooch on describing how their system functions, leaving the window open for doubt.
There's nothing wrong with choosing to rely on the audio ID rather than the decoding.

Yes, they could have made it more detailed but I don't really see the vagueness others do. In addition to my experience with the unit, the use of the term "radial" is a big clue for me.
 
GTN's have two fields in the nav frequency. One is the ID from the database and one is the decoded morse ID. Was a question during my IFR practical. Database ID comes up when you dial it, morse ID comes up a bit later after it reads the code.
 
One way to test it would be, to tune to the station, and see how long it takes for the station identifier to display in the window.

If it happens immediately, this indicates that it's most likely a database.

If it takes 5-20 seconds, then it's possibly listening to and decoding the Morse.

It doesn't happen immediately. There is a delay. Been flying the 530 a lot recently and it had me wondering this also? Also the DME figure on the 530. Is it using GPS or real DME to figure that out.
 
It doesn't happen immediately. There is a delay. Been flying the 530 a lot recently and it had me wondering this also? Also the DME figure on the 530. Is it using GPS or real DME to figure that out.
It's using GPS.
 
GTN's have two fields in the nav frequency. One is the ID from the database and one is the decoded morse ID. Was a question during my IFR practical. Database ID comes up when you dial it, morse ID comes up a bit later after it reads the code.
That's what you get. Morse UD when it can receive it,
It's using GPS.
Yup. If you are not DME equipped, you don't have DME.
 
Tuning in a VOR on the 530 gets me the VOR identifier, radial, and distance in the VLOC ident window.

I haven't been able to find this answer: Does the 530 listen to the Morse, then decode it and display it? Or is it using some database instead and just looking up the freq that's been dialed in?

I was looking this up today and came upon this post I found this...
In the 530w series installation manual (Google it. I'm not allowed to post links), on page 5-39 and 5-40 it takes about checking whether the Morse code decoder works for vors and localizers.

So it seems that the 530w does have a decoder.
 
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