On Tue, 08 Jan 2008 14:09:03 -0600, Gig 601XL Builder
wrote in
:

george wrote:
On Jan 9, 5:34 am, Mxsmanic wrote:

Sec. 91.21 Portable electronic devices.

(a) Except as provided in paragraph (b) of this section, no
person
may operate, nor may any operator or pilot in command of an aircraft
allow the operation of, any portable electronic device on any of the
following U.S.-registered civil aircraft:
(1) Aircraft operated by a holder of an air carrier operating
certificate or an operating certificate; or
(2) Any other aircraft while it is operated under IFR.
(b) Paragraph (a) of this section does not apply to--
(1) Portable voice recorders;
(2) Hearing aids;
(3) Heart pacemakers;
(4) Electric shavers; or
(5) Any other portable electronic device that the operator of the
aircraft has determined will not cause interference with the
navigation
or communication system of the aircraft on which it is to be used.
(c) In the case of an aircraft operated by a holder of an air
carrier operating certificate or an operating certificate, the
determination required by paragraph (b)(5) of this section shall be
made
by that operator of the aircraft on which the particular device is to
be
used. In the case of other aircraft, the determination may be made by
the pilot in command or other operator of the aircraft.

That is the Reg.
Self explanatory

(1) Portable voice recorders;

Is an iPod not a personal voice recorder? Yet all the airlines I've been
on recently include it in the don't turn on until we say so list.

While portable voice recorders fall under Paragraph B, there is a
report of an iPod causing interference in the cockpit:

From: (Don Poitras)
Newsgroups: rec.aviation.piloting
Subject: Bizarre radio experience
Date: Mon, 22 Oct 2007 19:26:27 +0000 (UTC)
Message-ID:
...
There's only one thing left to try...
I turn off my iPod that's plugged into the headset (not "Ride of
the Valkyries", but Amy LaVere)... silence. Wow. Cool. Plug back
in, "podunk..."

Somehow the combination of iPod, wire and LightSpeed 30-3G was
acting as a radio (a very crisp, loud radio) picking up multiple
frequencies at once. I wish I had written down all the airport
names so I could see how many I was hearing, but it was quite the
cacophony. I called LightSpeed and the guy there had never had
that reported before.