Subject: [NEXTEL-1] Re: About the NYT Articles

From: Marcel <[email-masked]>
Date: Sun, 10 Nov 2002 12:52:12 -0500

------- Original Message --------
From: "Steven J. Makky, Sr., ENP" <[email-masked]>
Subject:  Re: About the NYT Articles

NO!

The Port Authority maintained a complete repeater system operational on the 
"Citywide" frequency - 154.4300 MHz. Nothing else. The repeater was located 
in 5 WTC and had part of its signal coupled out to a very long run of 
Radiax radiating coaxial cable, cross-band couplers, bi-directional 
amplifiers and distributed antennas, mostly in mechanical and electrical 
rooms. The remainder of the power was sent to a roof-mounted corner 
reflector antenna that was beaming up toward the outside of the buildings, 
mostly to illuminate the rooftops and compensate for the very high 
noisefloor and against desensitization while operating on the roof. This 
was a carefully engineered system, not a mobile radio in a milk carton as 
speculation would lead to believe.

The repeater was usually kept "knocked down." There was a tone remote 
command that could be sent by at the Police Desk usually when the desk 
received a "Signal 8-8." This command enabled (or "set up") the repeater. 
The NY Times reports that this tone sequence was clearly audible at the 
beginning of the incident. Once enabled, a separate "knock down" code is 
necessary to turn the repeater off. That code sequence was not reportedly 
heard.

Is it possible to confuse this with other channels? Yes. Reports indicate 
that not only this system was used, but also 153.830 simplex, the Boro 
frequencies for Manhattan and Brooklyn, as well. It depends on what channel 
your boss orders you to keep your radio on.

The Port Authority Police operated on 453 MHz, as well as on a three 
channel EDACS 800 MHz trunked radio system. The building maintenance 
systems were on 470 MHz. ALL OF THESE SIGNALS - 154.4300 MHz, the 453 MHz 
repeaters, the 470 MHz repeaters and the 800 MHz trunked system were 
coupled into the one Radiax line that ran the building complex.

The fact that communications were occurring on the repeater at the time 2 
WTC went down - and the lack of communications in 1 WTC leads me to think 
that perhaps the transection of cable in 2 WTC interrupted the signal into 
the other building. The other building MAY HAVE received signal from the 
outside corner reflector antenna on top of 5 WTC, which accounts for 
sporadic traffic that was not readable on portables in the lobby. We didn't 
have a remote installed in the lobby when I worked for the Port Authority. 
This was likely a recent addition. There *should have been* adequate signal 
levels in the lobby if things were working normally.

Other potential points of failure: power failure on bi-directional 
amplifiers causing a loss of signal downstream, turning on a second mobile 
repeater on the same channel that the in-building repeater was on thereby 
creating contention between two repeaters in the same CTCSS tone with the 
same RF frequency.

The Port Authority did not have any VHF operations inside the WTC with the 
exception of supporting a repeater (maintained by the Port Authority) for FDNY.

In all of this speculation, let's never lose sight of the fact that this 
was an incident of extraordinary proportions and the Radiax/ BDA/ 
distributed antenna system was engineered to be resistant to most incidents 
- but no one could have predicted an insidious incident with such 
structural damage. There were thousands of fire calls and other emergencies 
that were handled effectively. There is a vast difference between designing 
a system that's fire resistant, bomb resistant and missile resistant (those 
planes were effectively missiles). The communications systems were indeed 
fortified to be bomb resistant in 1993. Who amongst us would have ever 
believed pre-Sept. 11th that a missile attack against the building was 
imminent? Given that denial, does anyone really think funding for a missile 
resistant system (if there is such a thing!) would have been granted 
pre-September 11th.?

Under the circumstances, it's a miracle that the system worked at all - 
even to the small extent it appears to have under impairment.

Steve Makky, Sr. (ex-PARS)

Peter wrote:

>Nothing says that they are really talking about a repeater. It might
>have just been a transciever on 154.43 or 153.83 on top of 5 WTC. I
>suppose it is also possible that everyone is confusing some PANY
>repeater channel for a FDNY channel. I had been told in the past that
>most companies near the WTC had PANY portables (?UHF - 453 Mhz or 470
>Mhz?)

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