who does VOR "calibration" for most accurate VOR approaches?

www.radiodaze.com/toolover.htm and look at their selection of alignment
tools. You can also go to the General Cement website
http://www.gcwaldom.com/catalog.html to see all the tools that you can get
from GC."Robert M. Gary" wrote in message
oups.com...

RST Engineering wrote:
Most VOR receivers/heads have a fairly accessable calibration control for
the VOR and another one for the LOC. Most of us who don't choose to
finance
our radio shop's owner to another week in Hawaii know how to find those
controls.

Easier said than done. The screw drivers that do that adjustment are
highly unique and seemingly impossible to find. My shop got theirs back
in the 50's. I spent about a month calling every place I could think of
to get the proper driver to adjust a basic King head and never got
anywhere. I think you need to wait around a shop until the old guy dies
and then grab his.

-Robert

Do you know what the name of the type of driver this is? I thought it
was just a spline driver but my shop said it wasn't. They were not sure
what it was called by they call it a "Cessna avionics driver" (even
though this is just a basic King head). They said if you tried to use a
regular spline driver it would probably strip the screws. Looking at
their driver it was the strangest shapped head I've ever seen.

-Robert

RST Engineering wrote:
www.radiodaze.com/toolover.htm and look at their selection of alignment
tools. You can also go to the General Cement website
http://www.gcwaldom.com/catalog.html to see all the tools that you can get
from GC."Robert M. Gary" wrote in message
oups.com...

So far as I know it is the smallest spline driver you can buy. At least
that's what I've been using for a goodly number of years.

Jim



"Robert M. Gary" wrote in message
oups.com...
Do you know what the name of the type of driver this is? I thought it
was just a spline driver but my shop said it wasn't. They were not sure
what it was called by they call it a "Cessna avionics driver" (even
though this is just a basic King head). They said if you tried to use a
regular spline driver it would probably strip the screws. Looking at
their driver it was the strangest shapped head I've ever seen.

-Robert

RST Engineering wrote:
www.radiodaze.com/toolover.htm and look at their selection of alignment
tools. You can also go to the General Cement website
http://www.gcwaldom.com/catalog.html to see all the tools that you can
get
from GC."Robert M. Gary" wrote in message
oups.com...

That's true. Even the 30 day rule was a compromise between
the needs of the still used tube radios and the solid state
radios. I have done ground checks at surveyed locations,
checks between two radios, had shops do a calibration and
done checks along an airway over a landmark. What I have
seen is that a poor antenna or a interference in the
airplane, such as a bad alternator, can cause problems.
Turn both VORs OFF and the needles will be centered, what
does that tell you? If the receiver is weak because of
antenna problems the needle sensitivity will be poor. If it
takes 15-20 degrees of knob turning to get full scale
deflection, the observation that the needles are within 4
degrees or 6 degrees of anything means very little, since it
is taking twice the standard deviation to move the needle.
A check within five miles of the VOR on the airport with a
VOT is legal, but check sensitivity. And check the system
along an airway at 30-50 miles every so often.


--
James H. Macklin
ATP,CFI,A&P

"RK Henry" wrote in message
news | On Wed, 12 Jul 2006 08:03:09 -0500, "Jim Macklin"
| wrote:
|
| Set the OBS to the published radial/course. In the old
days
| of vacuum tube radios, the tubes would change their
tuning
| as they got hotter and wore out. Thus the 30 day check
| rule. Modern solid state VOR are very stable and once
| adjusted are likely to stay within tolerance until they
| fail.
|
| Except that back then the rule required that the VOR check
be
| performed every 10 days. About 30 years ago, after
solid-state
| equipment became commonly available, the FAA liberalized
the rule to
| its present 30 day interval.
|
| RK Henry