Yes and no. The rule of 60 still applies, although the s/n ratio certainly
plays a part, given that we are talking about AM.

Bob Gardner

"John R. Copeland" wrote in message
...
It's signal-to-noise ratio that's the culprit, Bob, not radial spread.
A degree at the ADF antenna on the airplane is always the same size.

Either low signals or high noise will reduce ADF performance.
Everybody knows they get squirrelly around thunderstorms.
---JRC---

"Bob Gardner" wrote in message
news:0Zyub.182351$9E1.954218@attbi_s52...
It's a function of distance from the transmitting antenna...you have the
same "radial" spread situation that you have with a VOR in that one degree
spreads out 100 feet per mile from the antenna. The further you are away,
the slower the response. You should also know the class of the facility
from
the A/FD...an H beacon is good for 50 miles, HH is good for 75 miles,
LMM/LOM good for 15 miles, MH good for 25 miles. I've had many a pilot try
to pick up an outer marker from 25 miles away and gripe because s/he
wasn't
getting a good signal.

Bob Gardner

"Ben Jackson" wrote in message
news:4Iyub.178554$mZ5.1264586@attbi_s54...
My ADF (Narco 841) quit pointing shortly after I got the plane, so
I pulled it and found it was covered in swarf (metal shavings) so I
cleaned it off, cleaned the contacts (card edge connector) and put
it back in. Now it points again. What I'm wondering is: How fast
should it point? Let's say there's nothing on freq 200 (default)
and I tune a nearby NDB/marker on standby and hit swap. How fast
should the needle point? I realize that in flight it doesn't have
much call to move quickly, but until now I was never paying attention.

--
Ben Jackson

http://www.ben.com/