Wednesday, September 11, 2019

Experience as a Radio Engineer at One WTC

Every year on 9/11 I reflect back on my feelings on that day.  Watching the buildings burn and the impacts of those planes touch me personally.

I used to work and maintain radio equipment on One World Trade Center when I worked as an engineer for Southern New England Telephone's Paging system in NY,NJ at the time of the 1st bombing on February 26, 1993.


At One WTC we maintained a 72 MHz terrestrial radio link that fed data to all our paging transmitters in the NY,NJ area.  The data for this transmitter originated at our main paging terminal at 20 Exchange Place a few blocks away from the Trade Center buildings.

A week prior to the bombing our primary transmitter failed over to our secondary transmitter and I visited the site to investigate the issue to repair.  Yes real electronics as I used to do component level repair on radio circuits.  Trying to repair this equipment in the radio equipment area just below the roof of 1WTC is difficult and uncomfortable as it is very hot and lighting is very poor.  When you need tools or test gear it is about a 40 minute journey from the roof to the parking garage below 1WTC so after 1 or 2 attempts at making the repair I decided to pull the Primary unit and bring it home to my repair bench to better repair and burn in the unit after repair.

The next day I worked on the unit and replaced the components and aligned the drive for proper operation.

The following day I scheduled myself to do some system checks in the morning and after the peak NYC rush hour I would start my journey from my home in Northern NJ to One WTC hoping to have the unit installed and back in operation by just after lunch that day......Or that was the plan.....

While doing my system checks my wife told me she was not feeling well that day and there were signs of a few snowflakes coming down so I decided to push this replacement off another day rather then leave home and deal with snow in lower Manhattan.

I continued my system checks and had CNN on the TV in the background.  When the breaking news about smoke coming out of the bottom of the WTC interrupted the concentration on my work I was curious about what this issue was but at this point I was glad that I decided to delay my trip as this would have caused some issue getting near the building.

As details started to come out as to the extent of the damage and realization that this was the work of an explosion I continued to keep an eye on our system.  As a life long radio engineer I have always took my responsibility to keep systems operational very seriously and realized that thousands of people depend on my keeping things running especially in an emergency.

Later that night I received alerts that our WTC radio link lost AC power and was running on battery backup.  Time was very limited on the batteries and I was hoping this was a temporary power issue.  We were able to get contact with building personnel and were informed power and steam to the upper floors needed to be shut down due to the damage from the bomb damage.  When the batteries run down this would leave all of the greater NYC area out of service for our paging customers.

Realizing I had a good 72 Mhz link transmitter in my trunk I let my manager at SNET know that I had an option to keep the system running at some level.  I took the transmitter to our main paging terminal site at 20 Exchange Place.  20 Exchange Place is an older building and we had windows that could open.  I was able to bridge the modem audio that fed the analog circuit to WTC to this transmitter.  I then fashioned a simple dipole antenna out of a run of coax and suspended this vertically polarized dipole out the window with a broom stick.  I was not really pleased with the SWR reading off of this antenna but with some tweaking and I was able to get it to an acceptable level so the transmitter would not clip off and I was able to get about 80 percent of our transmitters in the NJ/NYC area back on the air keeping our customers and hospitals pagers in service.



It took some time of reflection of the timing of events of the day of the bombing.  I was glad that I procrastinated a little on that day due to my wife's illness and my desire to not head into lower Manhattan on a possible snow day.  If I would have left at my planned time there is a REAL good chance I would have been in the parking garage area when the bomb went off.

1 comment:

  1. Thanks for the blog and Great you did not go to WTC on that tragic day. Also to know how tough a Radio Engineer job could be.

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