Peter wrote:
> I am just going through some King video FAA IR training material and
> it briefly covers this topic.
>
> On a normal intercom one has selectors for "DME" and "NAV" and one
> would ident the VOR and the DME separately. However she mentions a
> that one can tell if one or the other is inop from the period of the
> ident. How does this work?
>
> Is she assuming some sort of mixed-mode intercom where there is just
a
> single "ident" selector? In that case, I can see that if the VOR
> (only) was inop then the ident would be heard every 30 secs (the DME
> ident) but what about if the DME (only) was inop? There would be some
> sort of strange periodicity.

The period of the ident (a missing ident every 4 as I recall) indicates
that the DME is not being transmited. Listening to the DME on the audio
panel just tells you that you are receiving the VOR (and will provide
the same audio the VOR does). Its really a test of the instrument's
reception.

-Robert

Hope I have read you Q correctly...

the VOR idents every ten seconds, the DME every 30. So you should
hear...VOR, VOR,DME, VOR, VOR, DME et seq. every minute.

The DME ident is higher in pitch than a VOR ident to aid your understanding.

If one item is failed but transmitting, you'll hear VORt where the t is
meaning "test". Or the ident might be changed to "test" or "tst". Either
way if it isnt what you expect to hear, dont use it for serious nav.

HTH

David

Oops, sorry...VOR VOR VOR DME, VOR VOR VOR DME!

> the VOR idents every ten seconds, the DME every 30. So you should
> hear...VOR, VOR,DME, VOR, VOR, DME et seq. every minute.
>

Think about it like this..

The VOR and DME are TWO SEPARATE radios and nav systems. They are on
different frequency bands, different transmitters and the only
assiciation that they may have is 1) being in the same transmitter
building and 2) being "paired" frequency wise with a VOR/ILS frequency.

For instance, every DME frequency is "assigned" a corresponding VOR
frequency to buddy-up to it. That way you dont have to know, and tune,
the UHF frequency that the DME operates at. You simply set your DME
reciever to "slave" to your VOR/NAV radio to get the selected frequency
pair assignment or you can tune the DME manually to the VHF "VOR"
frequency of the pair

The same frequency pairing exists for Localizer + Glideslope
installation. You tune the localizer.. the radio is set up to look for
the glideslope signal on a separate but assigned/paired frequency.

The VOR Idents occur regularly.. every 10 seconds or so.. and are heard
by using the VOR ident function on your radio/audio panel.

The DME idents occur regularly but every 30 seconds or so. They are
heard using the separate DME ident function on your radio/audio panel.

As others have said, if you monitor BOTH simultaneously you will hear
one "higher pitched" DME ident for every three "lower pitched" VOR idents.

If one is inop, the other signal and functionality is not affected.
Again, the only thing that the two share is a site, and the "pairing" of
two different bands on two different frequencies.

My home base, EFD, used to have a terminal VORTAC but had the VOR
function decommissioned. The TACAN remains, and the DME function of the
TACAN is tuneable by tuning the DME to its "VOR frequency pair" of 109.4
mhz.

Dave

Peter wrote:
> "david" > wrote:
>
>
>>Oops, sorry...VOR VOR VOR DME, VOR VOR VOR DME!
>>
>>
>>>the VOR idents every ten seconds, the DME every 30. So you should
>>>hear...VOR, VOR,DME, VOR, VOR, DME et seq. every minute.
>>>
>>
>
> Is this true if one is using an intercom which has TWO buttons for
> idents; one marked DME and the other marked NAV?
>
> I don't understand how a DME ident can be (as a general rule)
> incorporated into the VOR signal. One can have a DME without a VOR (an
> ILS, or a TACAN). I can ident the DME on an ILS even if tuned to a
> wrong ILS frequency (the DME on an ILS has a different ident from the
> ILS anyway) and as far as I can remember from flying in Greece I can
> ident the DME in a TACAN even though I can't receive the VOR part
> because it's on UHF.
>
>
> Peter.
> --
> Return address is invalid to help stop junk mail.
> E-mail replies to but remove the X and the Y.
> Please do NOT copy usenet posts to email - it is NOT necessary.

david wrote:

> If one item is failed but transmitting, you'll hear VORt where the t is
> meaning "test". Or the ident might be changed to "test" or "tst". Either
> way if it isnt what you expect to hear, dont use it for serious nav.

I was flying along in the back seat while Margy and her instructor where in
the front. They figured out the VOR was acting loopy and were listening
to the ID. They pretty much figured out it wasn't sending EMI, but they
were stumped. Finally, I pointed out it was sending TEST. (...and Margy
is an Advanced class amateur radio operator to boot!).

Peter > wrote in
:
> Is this true if one is using an intercom which has TWO buttons for
> idents; one marked DME and the other marked NAV?

Yes. If you listen to both simultaneously that's what you will hear. If
you only listen to one, then you'll only hear the one you're monitoring.

> I don't understand how a DME ident can be (as a general rule)
> incorporated into the VOR signal.

It isn't. It's on a separate frequency, but paired to the associated VOR
frequency. But it's easy to combine both signals through one switch,
thus saving a little money on the unit, and some prefer to hear both. I
prefer having separate monitor switches, but you can combine as many
signals as you like into one switch.

--
Regards,

Stan

Stan Gosnell > wrote:
>> I don't understand how a DME ident can be (as a general rule)
>> incorporated into the VOR signal.
>
>It isn't. It's on a separate frequency, but paired to the associated VOR
>frequency. But it's easy to combine both signals through one switch,
>thus saving a little money on the unit, and some prefer to hear both. I
>prefer having separate monitor switches, but you can combine as many
>signals as you like into one switch.

I assume at the VOR-DME ground station, the audio generators for the
VOR and DME must somehow be syncronized with each other, so the two
id's don't get scrambled?

Yeah but thats not hard surely? Each tx is synchd to a clock and the clocks
are set to zulu.


"Roy Smith" > wrote in message
...
> Stan Gosnell > wrote:
>>> I don't understand how a DME ident can be (as a general rule)
>>> incorporated into the VOR signal.
>>
>>It isn't. It's on a separate frequency, but paired to the associated VOR
>>frequency. But it's easy to combine both signals through one switch,
>>thus saving a little money on the unit, and some prefer to hear both. I
>>prefer having separate monitor switches, but you can combine as many
>>signals as you like into one switch.
>
> I assume at the VOR-DME ground station, the audio generators for the
> VOR and DME must somehow be syncronized with each other, so the two
> id's don't get scrambled?

Peter wrote:

>
> I am doing the FAA IR from the UK, and thought that perhaps they have
> a system in the USA where (the case of the DME and the VOR being
> co-located) the DME ident is combined into the VOR ident. Certainly
> the King training video gives that impression, but it doesn't make any
> sense to me.
>

While I've never used the King Video, I understant they are popular.

Every plane I've flown that had a DME had a separate switch on the audio
panel for the DME. When I went to Ident, however, I usually selected
both the VOR I was using AND the DME as a matter of expediency. So..
sorry that you ended up with faulty info.. but they are actually
separate in all regards except frequency pairing and location.... and
the location rule isn't hard and fast...

I recall there are a few approaches that use an ILS... but you tune the
DME from the on-field VORTAC for DME information during the approach.
Two separate installations altogether.. and in this case, the idents
would be different as well.

Dave

Peter asked, "... does anyone actually do that [identify DME and VOR
together] , if they have an intercom which has separate DME/VOR ident
buttons, for navaids that have the same ident?"

Yes. I identify both at the same time and switch off whichever one I hear
first.

Jon

Peter > wrote in
:

> Yes, and it makes me wonder what they do when the two aren't exactly
> co-located. I wonder if there is any sync between e.g. the Biggin ILS
> ident and the Biggin VOR ident (both of which have a DME of their
> own).

AFAIK they are always colocated. If the ILS has its own DME (which isn't
always the case) then the DME will on a different channel, and have a
different ID, than the one with the VOR. If the ILS doesn't have its own
DME transmitter, then there will be no DME ident when you are tuned to
the localizer, *unless* you have set the DME to hold on the VOR, in which
case you will receive the DME ident off the VOR, and they may not by
synchronized. I regularly do this at my home base, where the ILS has no
DME, but the VOR is on the field. It's not usable for anything except
situational awareness, but in some cases it can be used for identifying
fixes on the approach, depending on what the approach chart says. I've
never worried about the synchronization, because we have separate monitor
switches for the nav and DME.

--
Regards,

Stan

"Jon Woellhaf" > wrote in
:

> Peter asked, "... does anyone actually do that [identify DME and VOR
> together] , if they have an intercom which has separate DME/VOR ident
> buttons, for navaids that have the same ident?"
>
> Yes. I identify both at the same time and switch off whichever one I
> hear first.

That's what everyone I fly with does. You never know where in the
sequence you'll come in, so you listen to both until you get an ident,
note it, and then turn it off so you don't hear it again. There usually
isn't time to be spending a lot of time doing this, because you usually
do it fairly late in the approach sequence. We can usually only tune the
final navaid after receiving vectors for final, so time becomes
important.

--
Regards,

Stan

In article >, Peter
> wrote
>
> "Robert M. Gary" > wrote:
>
>>The period of the ident (a missing ident every 4 as I recall) indicates
>>that the DME is not being transmited. Listening to the DME on the audio
>>panel just tells you that you are receiving the VOR (and will provide
>>the same audio the VOR does).
>
>Is the above true for intercoms that have separate ident buttons for
>the DME and the VOR?

Not on the ones I've used. Different pitch, different period.

--
Richard Herring >

On Wed, 19 Jan 2005 16:46:35 +0000, Peter wrote
(in message >):

> I am aware of the frequency pairing etc. I've been flying IFR for 2-3
> years and have always navigated entirely IFR. What confused me was the
> concept of identing both together - does anyone actually do that, if
> they have an intercom which has separate DME/VOR ident buttons, for
> navaids that have the same ident? I've done that for navaids that have
> different idents and then the two different idents are obvious.
>
> I am doing the FAA IR from the UK, and thought that perhaps they have
> a system in the USA where (the case of the DME and the VOR being
> co-located) the DME ident is combined into the VOR ident. Certainly
> the King training video gives that impression, but it doesn't make any
> sense to me.

The two systems are separate, but the ident from the VOR has a gap when the
DME transmits. If you select both then you the combined audio from both
navaids, but the result is a continous stream of idents :

VOR VOR VOR VOR VOR VOR VOR
DME DME

which you hear as :

VOR VOR VOR DME VOR VOR VOR DME VOR


There is nothing magical, it's just that the ident system is configured such
that the VOR misses every fourth ident, and the DME is synchronised to
transmit during this gap.



If one of them is switched off you would simply not hear it, as in :

VOR VOR VOR VOR VOR VOR VOR

or

DME DME


Or if the DME (say) were in test mode then you might hear :

VOR VOR VOR TST VOR VOR VOR TST VOR


Now, do I select both ? Well I struggle to ident anything (still at the "have
patterns written/printed on plog" stage), and I certainly haven't mastered
the finess of telling them apart ! So, no I don't.

Simon

"Simon Hobson" > wrote in message
et...
> Now, do I select both ? Well I struggle to ident anything (still at the
> "have
> patterns written/printed on plog" stage), and I certainly haven't mastered
> the finess of telling them apart ! So, no I don't.

You and me both. Anyway, what's the harm in writing them down - means you
can concentrate your brain on other things :-)

D.