From: acg@hermes.dlogics.com (Andrew C. Green)
Newsgroups: comp.dcom.telecom
Subject: Review of Ameritech Personal Communication Service
Date: 12 Nov 92 16:57:51 GMT
Reply-To: acg@hermes.dlogics.com
Organization: TELECOM Digest
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X-Telecom-Digest: Volume 12, Issue 841, Message 1 of 5

You may recall that several months ago, I reported my being signed up
for a long-term test of Ameritech's Personal Communication Services.
This is essentially a cellular-phone type of network, but uses
digital-transmission radio frequencies between the user's portable
phone and local transceivers.  The idea is to develop a very small
cell network (i.e. approximately 1/4 mile per cell) using 10mw digital
transceivers for handsets. Ameritech has wired up sections of downtown
Chicago, the Lincoln Park residential area to the north, and downtown
Arlington Heights in the northwest suburbs. For the record, I'm using
"cellular" as a shorthand description, though Ameritech itself does
not describe the PCS as such.

At the end of September I finally received a call from Ameritech: they
had received their latest batch of prototype phones, and was I still
interested in joining the test? I said I was.  :-) A huge box soon
arrived, containing the following items:

1) The PCS phone itself, a flip-style pocket phone. It's 6 1/2" long,
2 1/4" wide and 1 1/4" thick, with a single-segment 4" flexible whip
antenna. The literature claims a weight of 6.6 ounces, though with the
3.6-volt battery installed (roughly the size of two AA batteries), it
weighs in by my measurements at a porky 7.3 ounces. ;-)

2) A small charging stand for the phone powered by a brick transformer.  
It includes a recessed port for simultaneous charging of the spare 
battery (included).

3) A "base station", 9"W by 6 1/2"D by 3"H, which connects to your
home phone line and allows the PCS to function at home as a cordless
phone.  The base station itself also functions as a very nice
speakerphone and signalling intercom to the PCS. It's powered by yet
another brick transformer and six AA backup batteries.

4) A quantity of instructional documents, including a slick glossy
manual for the PCS, an instructional videotape and a map showing the
service areas for making calls in downtown Chicago, Lincoln Park and
Arlington Heights.  Ameritech told me today that they are currently
expanding the service area with additional transceivers, though the
new boundaries are unclear.

A number of immediate observations here:

1) The phone and base station both arrived in retail-quality packaging
bearing a "SilverLink" logo, and the base station's packing list
mentions an instruction manual that was not found. Apparently they are
existing products that have been modified for the PCS test. Ameritech
did tell me that the phone was a current model that had been modified
with a pager unit. I noticed it also didn't match the unit shown in
the videotape, which they said was a non-pager prototype.

2) The host of the instructional video should be beaten with sticks.
My wife and I had to really grit our teeth through a variety of awful
Star Trek "Beam-me-up-Scotty" jokes and insulting European accents in
a segment about international calls before we were done. Anyone who
gave up on the videotape halfway through would miss some information
at the end.

3) It would be nice if the production-model PCS base station had the
phone charging stand built in. This would save quite a bit of space
and spaghetti wiring.

The phone itself: It operates in two modes: Public (i.e. a cellular
phone) and Private (a cordless extension phone). It has a small LCD
display and 18 backlit soft-touch buttons covered by the flip-type
microphone cover. A rubber-like molding around the perimeter contains
Mute/Backlighting and Volume Step-Up/Step-Down buttons. The molding
itself is a weird aqua blue color that gives a sort of toy-like look
to it ("Hot new PCS colors for Fall: Strawberry and Wild Peach!!!").
Setup options include Pager On/Off and Phone On/Off, the latter for
keeping the phone on when the cover is closed, required for ringing
the phone from the base station in Private mode. It can store up to 30
frequently-called numbers and five received pages; the numbers are
scrolled on its screen and can be dialed automatically off the
display.  As a side-note, the phone makes a variety of cheerful
warbling tones to confirm commands; this apparently is the source of
the stupid Star Trek communicator jokes on the videotape.

Making a call is more conventional than cellular. You open the phone
and press a green button to get a line. The phone apparently "pings"
the nearest transceiver (or base station) to get an open line, and
once a handshake is established, you get a dial tone. At this point
you dial your phone number. I found this tricky; the PCS tries to
buffer the digits as you dial, but often tends to drop digits or fire
off truncated DTMF tones that are too short to register. Dialing
slowly is recommended, though its redial feature can rattle off the
tones with no problem.

Incoming calls are handled in a sort of indirect fashion. Unlike a
typical cellular system, the PCS network has no idea where any
particular phone is, and therefore cannot ring it directly. Callers
dialing your number are routed to an Ameritech Voicemail box where
they are directed (by your own greeting or a company-supplied default)
to leave a voice message or to punch in a phone number.

Callers leaving voice recordings will trigger a page to your PCS phone
with your own number displayed; you then call it and play back your
message(s) after entering a seven-digit password. Callers entering DTMF
numbers will trigger a page of that number to the PCS. (Any voice
message from that same DTMF call is discarded, I found.) In either
case, the incoming page number is displayed on the PCS, and (assuming
you're within the service area) pressing the green Call button will
automatically dial the displayed number for you. As the PCS uses an
existing pager network, the performance has been fine throughout the
Chicago area, with only one attempted page lost that we know of so
far.

Call quality with digital transmission is, as you might expect,
superb.  The phone does suffer from frequent dropouts, however,
depending on battery strength and your proximity to the transceiver
antenna. Callers tell me that they don't notice dropouts as much as I
do; perhaps some software somewhere is filling in short dropouts with
interpolated values, although I found it rather distracting at my end.
A boost in power from 10mw would be nice, as on one occasion I was
standing within 40 feet of an antenna and still getting dropouts. The
phone is supposed to generate a warning tone before you blunder out of
range and lose a call, but I found in practice that dropouts became so
severe at long distances that the warning tone, which I have yet to
hear, would be somewhat redundant.

So do I like the PCS? Yes. Its small size is a big asset, its digital
transmission quality is exceptional (dropouts aside) and secure, and
its pager system for incoming calls is an acceptable compromise, as it
is not positioned as a competitor to a cellular phone. I see the PCS
as a sort of low-end communication device suitable for the occasional
caller; in fact the early brochures I received show scenarios such as
a lady shopping at our local supermarket and kids at an amusement
park. The only snags I can see at the moment are the low power
limitations, which presumably can be bumped up if necessary, but
primarily the density of transceiver installations required under the
current design. Packing antennas and phone lines into infrastructure
at the rate of one every quarter-mile or so seems like quite an
undertaking to me.

I want to add a particular good word for their 800 support line:
granted this is a test program, and one should expect the
highly-competent support we are getting for this, but it is
nevertheless extremely satisfying to have one's call for help answered
promptly by people who have all the answers at their fingertips, as
opposed to being put on hold by Public Relations salesdroids who can't
answer a simple question.

This test program is scheduled to continue through the end of next
year, and I'll post further developments as they occur.


Andrew C. Green
Datalogics, Inc.      Internet: acg@dlogics.com
441 W. Huron          UUCP: ..!uunet!dlogics!acg
Chicago, IL  60610    FAX: (312) 266-4473