Getting The Most Out OF The Milestone-311
The Milestone-311 is a digital voice recorder and MP3 player. It was specifically
designed to meet the needs of blind or visually impaired users. In fact, it does not even
have a visual display. All of its functions are supported by speech. As a simple memo
recorder and MP3 player, it works quite well, but in my opinion, if its functionality were
that limited, it would be much more difficult to justify the cost. However, it also has the
capability of making high quality stereo recordings using external sources. In addition,
because it supports SD memory cards, it handles storage of large amounts of MP3 data,
making it a practical option for taking audio books with you when you are on the road. I
will elaborate on these aspects of the device later in this article.
The Milestone-311 is very small, about the size of a credit card, but thicker, of course.
The unit contains 256MB of internal flash memory and is equipped with a slot which
accepts SD memory cards of any size. I am currently using a 2GB card. The internal
memory allows roughly two hours of recording using the internal microphone. This is
primarily designed for memos, lists, etc. With a 2GB memory card installed, however,
you have much more flexibility. With the recorder oriented properly, the five primary
controls are visible. The card slot is on the right side of the unit. The five main buttons
are arranged in a cross shape, sometimes called a joystick pattern. These buttons are:
- Record: round button with small indent.
- Play button: at the center of the cross, flat surface.
- Rewind button: embossed with a left-arrow.
- Fast-forward button: embossed with a right-arrow.
- Mode button: bottom button, embossed with a cross.
Along the top of the recorder, there is a sixth button, the Selector, followed to the right by
a mini USB port, and a charge jack. At the bottom of the unit at the right is a 1/8-inch
stereo phone jack which performs both input and output functions. There is also a cut-out
with a fastener for a neck lanyard. On the face of the unit below the five main buttons is
a group of small holes for the internal speaker. Finally, there is a small LED on the face
in the upper left corner, which is the only visual indicator.
The recorder is powered by a built-in rechargeable lithium battery. The manufacturer
estimates that the unit will record for roughly ten hours on a single charge. Should the
battery ever require replacement, the unit must be sent in for service. This is a bit of a
drawback, but given the use of a lithium battery, the life expectancy is much greater than
it would be for standard NiMH batteries. There is also no danger of causing the
formation of memories in the battery by recharging before the battery is fully discharged.
For quick notes or conference recording, the internal microphone does quite well. I
recommend sitting reasonably close to the sound source for best capture. The internal
microphone produces a highly compressed mono MP3 recording, and is therefore most useful
for recording speech. It uses a bit rate of 32KBPS. On a 2GB SD memory card, this
translates to roughly 140 hours of recording. It is, however, much better sounding than
other digital voice recorders using similar techniques. For high quality stereo recording,
you must use an external source, which can only be accomplished when using a memory
card. The internal memory only supports recording from the internal microphone. This
is understandable, as the limited available memory would not allow for much recording
time. When recording from external sources, the Milestone-311 produces a stereo MP3
file at a rate of 192KBPS. Using a 2GB SD memory card, this translates to roughly 24
hours of recording. This is nearly CD quality and sounds excellent.
There are two ways to make a recording. You can press the Record button and simply
hold it while speaking into the microphone. The recording continues until you release the
button. For longer continuous recordings, press the Record button and while holding it,
press the Play button. The recorder emits a pair of beeps: a low-pitched beep followed by
a higher-pitched beep. Then, you can let go of both buttons and recording begins and
continues until you again press and release the Record button. When you end the
recording, you will hear two beeps, like you did when starting, but in reverse order.
Recordings can be made using either the internal memory or using a memory card.
The Selector button on the top edge of the recorder is used to switch between the memory
recorder choices. A third available selection is the MP3 player, which can play MP3 files
stored on the memory card. Each time you press the selector button, the unit switches
from one application to another: Internal Memory Voice Recorder, Memory Card Voice
Recorder and MP3 Player. Once you have moved through the three applications, you
simply press the Selector button once more to begin cycling through them again. If you
want to hear a status of your current application, press the Mode button, which is the one
with a cross on it, at the bottom of the group of five buttons. Hold it in for at least 1.5
seconds. The unit will report the current application, current folder number, percentage
of available memory and battery charge status. While you are in one of the voice
recorder applications, you can access any of five folders for organizing your recordings.
To select a folder, press the Selector button, and while holding it, press one of the five
buttons on the main surface of the recorder. The buttons correspond to folders as
The folders are announced as one, two, three, four and five.
You can add your own spoken labels to folders by using the folder selection buttons as
just described, but keep the buttons pressed for at least 4 seconds. You will hear the
beeps indicating that recording is ready to start. Keep the buttons pressed until you have
spoken the name you wish to assign to the folder. Release them and the next time you select the folder you will hear your voice announcing its name.
The play and navigation functions are logical and much as you would expect. The Play
button is pressed to play or pause the recorder. The left and right arrow keys are used to
navigate within a folder. The MP3 player uses similar navigation, but adds the ability to
move into and out of folders. This is done using the Mode and Record buttons. The
Mode button moves down into a folder, while the Record button moves up one level. In
the MP3 player application, you can label a folder by navigating to it, and then using the
keys: Selector and Record pressed together. This works in the same manner as labeling
in the recorder applications.
There are other keyboard details such as erasing of messages which I will not describe as
they are handled very nicely in the electronic manual which is included on the Milestone-
311 itself. You must connect it to your computer using the supplied USB cable and then
you can read the manual or copy it to your hard drive for future reference. One important
key combination which I will mention is the locking mechanism. If you press and hold
the Mode button and press the Record button, you will lock the keyboard. This is handy
if you are going to carry the unit around and could inadvertently press a button. To
unlock the keyboard, you press the same key combination once more. Also note that the
recorder does not have a power switch. It goes into sleep mode after ten minutes of
inactivity. To awaken it, simply press one of the five main buttons. It will announce the application it is currently in, and if
applicable, the current folder. If it was locked, it will announce that also. However, when it is awake, if it is locked and you begin pressing buttons, there will be no
response. This is because it is locked. Before you panic, try pressing the unlock
For the remainder of this article, I will focus on two ways of expanding the use of the
Milestone-311. The first is the use of text-to-speech software to produce MP3 files
which can be transferred to the recorder and played while you are away from your
computer. There are many software tools available which provide this function, but my
favorite is a product called TextAloud. It is a nifty little program which can read files to
you, or generate MP3 files for later use. It is shareware, so you can download it and try it
before you buy it. It costs about $30. As an option, you can also purchase the AT&T
Natural Voices for it, which produce fantastic quality speech. I have produced a copy of
this article using this program and the AT&T Crystal voice. Listen to it, and I think
you will agree that it is great for converting reading material to MP3 files and taking them
The other way to extend the use of the Milestone-311 is to record from external sources.
As mentioned earlier, you can only do this from the memory card recorder.
To set up the recorder to use an external source, press and hold the Selector button, and then press both arrow keys. This temporarily switches the phone jack to function as an input connector. The normal arrangement of the Milestone-311 is to use the jack for output connection to headphones.
Once you have set the unit for external recording, you can connect the source and then use standard procedures to begin recording. If you press any key other than the Record button after setting the unit for an external source, the unit will reset and the next recording will be made using the internal microphone.
The complication with external recording is the way in which the recorder operates in this mode.
Due to design constraints, the Milestone-311 uses one stereo jack to handle headphone
output and external input. This means that you can not monitor recordings while you are
making them. It also means that the input impedance expected by the recorder when used
with external sources is low, like that of a set of stereo headphones, that is, 32-ohms.
This permits direct recording from the headphone jack of a stereo portable radio,
Walkman or other such device. When you do this, you must use moderate volume levels.
The expected signal level is roughly the level produced by line-level devices, but at the
low impedance. This presents a problem when it comes to such things as external
microphones and standard line input devices.
After many hours of Internet searches, I found a reasonable solution to this problem. It
is a device called Mymonitor. Which is designed as a monitor for vocalists. It is a
small mixer with a mono microphone XLR input and a stereo line input. It has two stereo
headphone outputs. There are two level controls, one for each of the inputs. It would be
practically perfect if it had a stereo microphone input, but that is about the only thing it lacks.
Since it has headphone outputs, it works very nicely as a mixer for feeding the Milestone-
The second headphone jack also enables you to plug in a set of headphones and
monitor the signal being fed to the recorder. It is not quite as good as monitoring the
recording itself, but it beats having no feed at all. For microphone recording, you must
use an amplified stereo microphone, or you can opt for a monaural recording using a
standard dynamic microphone through the XLR input. I have both. The stereo
microphone I found is made by The Sound Professionals and is the SP-Booster-1.
The combination just described will produce good quality stereo recordings, suitable for
conversion to CD tracks. You will probably want a good CD burning package such as
Nero or another favorite. I should mention that the Mymonitor product as well as the SP-
Booster-1 are both powered by batteries. The Mymonitor also comes with an AC
adapter for connection to commercial power when it is available. Since I will be using
the Milestone-311 for some field recording, I have purchased a camcorder case which
holds all of the accessories described in this article. Certainly, for applications which do
not require higher quality sound, I will simply tuck the recorder itself in my pocket and
use it stand alone. As I said, it does a good job in this mode for general-purpose
recordings. For reference, I have included a list of the components which comprise my
field recording system as described here. I hope this helps you to maximize your use of
The Milestone-311 is available at:
Independent Living Aids
The text-to-speech software I use is:
The amplified microphone I use is:
Sound Professionals Amplified Stereo Omnidirectional Microphone.
To adapt the 1/8-inch stereo plug of the microphone to the 1/4-inch stereo jack on the
mixer, I use:
1/8 inch Stereo Jack to 1/4 inch Stereo Plug Headphone Adapter
Radio Shack Item#: 274-367
The mixer and impedance matching device which I use is:
ART MyMonitor My Monitor Personal Headphone Monitor Mixer
Available from several sources including
Music Works Group
To accommodate standard line outputs from audio components, you can use:
6-foot cable, 1/8 inch stereo plug to 2 phono plugs
Radio Shack Item#: 42-2551
To feed the output from Mymonitor to the Milestone-311, I use:
Sound Professionals 1/4 inch Stereo Phone Plug To 1/8 Inch Stereo Phone Plug.
For monaural vocal or spoken input I use:
AT-MB1KC - Audio Technica with XLR cable
Available from Sound Professionals.
The MP3 version of this article is here.
Return to our Assistive Technology page