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Dave Jacobowitz
March 16th 04, 12:56 AM
Hey... have been flying instrument practice in the Bay
Area for the past couple of months and have been flying
NDB approaches without any trouble, but yesterday I
was setup for the OAK NDB 27R and could not get the
station. Needle didn't point and could not get the
identifier.

Tuning the ADF to other stations, like KGO AM or
REIGA compass locator works fine. Every station I
tried except RORAY (OAK compass locator) worked.

Still, we requested and were granted the NDB
approach at OAK and that seems like it would have
been a good time to tell me that that RORAY compass
locator was OTS. Nobody said anything.

Later, on the ground, I looked over NOTAMS to see
if there had been a frequency change or other problem
with RORAY, but I couldn't find anything.

Any ideas? Do I need to investigate this further?

My instructor figures that it's something screwy
about the OAK NDB transmitter, not the ADF in my
rental aircraft. But what kind of screwy could
it be? It either works or not, right? I guess I
can imaging frequency drift from 341 kHz to 340.5
kHz or something, but is the front end of an ADF
that selective?

It'll be embarassing on my very soon upcoming
checkride if I take a plane up with an supposedly
working ADF and then can't fly approaches with it.
I would think the DE would want to know why it
was not placarded if it was known to be flakey.

Any advice welcome.

sincerely,
-- Dave
jacobowitz73 -at- yahoo -dot- com

Brad Z
March 16th 04, 02:41 AM
Dave- were you able to ID the morse code identifier?

"Dave Jacobowitz" > wrote in message
om...
> Hey... have been flying instrument practice in the Bay
> Area for the past couple of months and have been flying
> NDB approaches without any trouble, but yesterday I
> was setup for the OAK NDB 27R and could not get the
> station. Needle didn't point and could not get the
> identifier.
>
> Tuning the ADF to other stations, like KGO AM or
> REIGA compass locator works fine. Every station I
> tried except RORAY (OAK compass locator) worked.
>
> Still, we requested and were granted the NDB
> approach at OAK and that seems like it would have
> been a good time to tell me that that RORAY compass
> locator was OTS. Nobody said anything.
>
> Later, on the ground, I looked over NOTAMS to see
> if there had been a frequency change or other problem
> with RORAY, but I couldn't find anything.
>
> Any ideas? Do I need to investigate this further?
>
> My instructor figures that it's something screwy
> about the OAK NDB transmitter, not the ADF in my
> rental aircraft. But what kind of screwy could
> it be? It either works or not, right? I guess I
> can imaging frequency drift from 341 kHz to 340.5
> kHz or something, but is the front end of an ADF
> that selective?
>
> It'll be embarassing on my very soon upcoming
> checkride if I take a plane up with an supposedly
> working ADF and then can't fly approaches with it.
> I would think the DE would want to know why it
> was not placarded if it was known to be flakey.
>
> Any advice welcome.
>
> sincerely,
> -- Dave
> jacobowitz73 -at- yahoo -dot- com

Ron Rosenfeld
March 16th 04, 03:07 AM
On 15 Mar 2004 16:56:59 -0800, (Dave Jacobowitz)
wrote:

>Tuning the ADF to other stations, like KGO AM or
>REIGA compass locator works fine. Every station I
>tried except RORAY (OAK compass locator) worked.

Were you able to positively identify the Morse Code identifier? If so,
there may well have been something screwy with the avionics in the a/c. Or
perhaps the signal was weak, or being interfered with.
Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

Dave Jacobowitz
March 16th 04, 05:53 PM
Ron Rosenfeld > wrote in message >...

> Were you able to positively identify the Morse Code identifier? If so,
> there may well have been something screwy with the avionics in the a/c. Or
> perhaps the signal was weak, or being interfered with.
> Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

Negative. I got neither a needle indication or was I able
to ID the station audibly. (but was able to get others).

Everything points to the station being the problem,
not the box in my A/C, but again, there were no notams
and I was cleared for that approach.

-- dave
-- jacobowitz73 -at- yahoo --dot-- com

John Harper
March 17th 04, 01:24 AM
I suspect the controllers just didn't know. I've been involved in exchanges
where someone asks whether the XXX VOR is out of service, and
the controller says "not as far as I know" so a bunch of pilots try it
and all report it u/s. The controller says "thanks, I'll report that".
After all, nobody actually uses NDBs - certainly not that one -
except for practice approaches.

John

"Dave Jacobowitz" > wrote in message
om...
> Ron Rosenfeld > wrote in message
>...
>
> > Were you able to positively identify the Morse Code identifier? If so,
> > there may well have been something screwy with the avionics in the a/c.
Or
> > perhaps the signal was weak, or being interfered with.
> > Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)
>
> Negative. I got neither a needle indication or was I able
> to ID the station audibly. (but was able to get others).
>
> Everything points to the station being the problem,
> not the box in my A/C, but again, there were no notams
> and I was cleared for that approach.
>
> -- dave
> -- jacobowitz73 -at- yahoo --dot-- com

Dave Jacobowitz
March 18th 04, 05:57 PM
I think this is the most likely scenario, too. Thanks for
the feedback, John. As an instrument student, I've never
flown anything put practice approaches (though some of those
were in actual ;)

I wonder how many NDB approaches I'll be using once I've
got my ticket. But you're right, it's kind of hard to take
the ndb to 27r at oak when there's a lovely ILS right there.

-- dave j

"John Harper" > wrote in message news:<1079486818.506172@sj-nntpcache-3>...
> I suspect the controllers just didn't know. I've been involved in exchanges
> where someone asks whether the XXX VOR is out of service, and
> the controller says "not as far as I know" so a bunch of pilots try it
> and all report it u/s. The controller says "thanks, I'll report that".
> After all, nobody actually uses NDBs - certainly not that one -
> except for practice approaches.
>

Ron Rosenfeld
April 1st 04, 12:58 AM
On 16 Mar 2004 09:53:32 -0800, (Dave Jacobowitz)
wrote:

>Negative. I got neither a needle indication or was I able
>to ID the station audibly. (but was able to get others).
>
>Everything points to the station being the problem,
>not the box in my A/C, but again, there were no notams
>and I was cleared for that approach.

Since you were not able to ID the station, but were able to ID other
stations, then either there is something in your a/c interfering with
reception on that particular frequency, or there was a problem with the
station.

The fact that you were cleared for the approach by ATC is irrelevant, and
the absence of a NOTAM might mean only that no one else noted the problem
at the time you flew. Many NDB's are not monitored, so ATC has no way of
knowing if it is functioning or not. Furthermore, given the proliferation
of approach approved GPS equipment, it is possible to be cleared for an NDB
approach with the NDB OTS.

You could troubleshoot by flying in the vicinity with the same a/c, and
seeing if you can now receive the station. If you cannot, check it with
other equipment (or ask another a/c in the vicinity to check it).


Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)

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