Charleston (SC) Microwave Tower
- Just returned from a business trip to Charleston South Carolina. Across from the College of South Carolina is a short microwave tower on top of a Bell South Building. There is one large microwave (KS style) horn and another strange looking horn. Any idea of its history and whether it was part of the cold war apparatus? I was going to stop by and ask but got tied up on other business.
- Doubt it is if it was on a BellSouth facility. BellSouth here locally
(Chattanooga, Tennessee) used microwave to link some remote central offices
to the tandem here, up until around the late 80s or early 90s, when it was
all replaced with fiber.
Got any photos? If you go to
http://www.qsl.net/kf4lhp/telco/scb-georgetown.html and look at the photos
there, I have up-close shots of the different types of microwave antennas
used. There are three different types, but all are 6 GHz band antennas.
I looked through the licenses and only AT&T has a current license for any
microwave stuff down there, so it's probably been turned down.
Matthew Sadler, KF4LHP mws@...
http://kf4lhp.virtualave.net/railfan/ Tennessee Valley Railfanning
http://www.kf4lhp.net/ Chattanooga's amateur radio & scanner resource
----- Original Message -----
Sent: Friday, January 07, 2000 8:45 PM
Subject: [coldwarcomms] Charleston (SC) Microwave Tower
Just returned from a business trip to Charleston South Carolina. Across
from the College of South Carolina is a short microwave tower on top of a
Bell South Building. There is one large microwave (KS style) horn and
another strange looking horn. Any idea of its history and whether it was
part of the cold war apparatus? I was going to stop by and ask but got tied
up on other business.
- Back in the old days of the Bell System, it was not uncommon for
Long Lines and the local operating telephone companies to
colocate equipment in a local central office. In those days, Long
Lines often brought their long distance trunks into a main central
office for an area. For example, the Allentown CO in Allentown, PA
(CLLI ALTWPAAL) had a sizeable array of KS horns on a two-level
platform on the roof. Long Lines had some rooms in the upper
levels of the building where they handled the RF and some of the
demultiplexing, then handed off the circuits to the Bell of PA Toll
frame on the floor below. Once divestiture was ordered, the
arrangement for the handoff of toll traffic changed, so that now the
local telephone company carries the circuits from the AT&T point of
presence (in the Allentown case, their Lanark tower, CLLI
LNRKPA) to the local central offices. Eventually, Long Lines
moved out of the Allentown CO, and the KS horns and platform
It's not unusual for local CO's to have KS or other microwave horns
to interface with the pre-divestiture Long Lines networks. Other
local CO's have microwave links for inter-office links where the
topography does not favor running cables (ie, Bois Blanc Island to
the Cheboygan CO in northern Michigan). There is even a KS horn
on the old local CO here in State College. The old CO is now used
for Bell Atlantic's engineering offices, and a newer CO is a block
away. I doubt highly that the microwave link is still in use.
An important thing to remember is that with the exception of
certain specific facilities, ie-Autovon switches and hardened cables
to military installations, almost all Bell System facilities were dual-
use carrying civilian and military traffic. I would expect that the
vast majority of circuits anywhere carried civilian traffic, just
because that volume would far outweigh the military traffic. So
even the majority of circuits carried over even the hardened L carrier
routes probably carried regular mom and pop long distance calls. If
someone has other information, let us know. Thus, just because
you see a facility with KS horns, don't automatically think "military"
rather, think dual-use. Any Bell System facility could be used for
either purpose. Military circuits may very well have ridden in the
same cable sheath as civilian, maybe even within the same carrier
Keep in mind that AT&T was a business first...PROFIT was the
main motive for what they did. If they hardened a route, it was
because they got paid to do it, or otherwise had an incentive,
regulatory or contractual. It just wouldn't make business sense to
build separate networks for civilian and military traffic. Moreover,
because of the benefits of diversity, the military was better served
by sharing the civilian network, enjoying much better survivability
and redundancy than if they had a dedicated network.
From what my AT&T contacts tell me, they had been keeping a lot
of the microwave circuits live over the past 10 years, so that they
would not lose the licenses and the valuable spectrum they
represent. I imagine with the regulatory changes and auctioning,
that strategy has been abandoned, since much of this equipment
has been removed now. The last time I was in Lanark, all the old
microwave equipment was gone, and the only things left were
some direct microwave links to larger customers, allowing them to
bypass the local Bell network for their long distance traffic.
Going back to the post-divestiture network topology...since the
local telephone companies have to switch and carry the ends of the
long distance calls...where things are a LOT more complicated
than moving a call across the country...I can't understand why
everyone is on the AT&T bandwagon to reduce the fees they pay to
the LEC's for originating/completing these calls. SOMEONE has
to pay for all the stuff connecting you to them!
Nuff Said...(can you tell i am an ex-Bell manager?)
Mike Jacobs, N3YAV
Antenna and RF Engineering Laboratory
Penn State University
State College, PA