I hear that.
The last time I flew, the guy at the TSA x-ray told me to take off my
shoes and belt. I laughed, thinking he was joking and he didn't
reply. He repeated it as the two Nat'l Guardsmen with M-16s took a
step forward. I loudly said COMPLIANCE and hurriedly removed them
and set them in the bucket for scanning. That was mid-morning the day
the "shoe bomber" had been nabbed. I was flying to Alaska for my 50th
birthday 14 years ago. My Nikes and belt passed OK and the Guardsmen
stepped back. Interesting morning. Later, I saw the flash on the
right wing, the plane shuddered, and a loud crack sounded. We were
struck by lightning on approach to SeaTac. The cabin lights dimmed,
but the engines didn't skip a beat. 'Twas me first strike.
Do not let your fire go out, spark by irreplacable spark.
In the hopeless swamps of the not quite, the not yet, and
If you've ever worked around a tower that was struck by lightning,
you'll know first hand what that induced magnetic pulse can do to
unshielded circuits. I spent hours on cross country phone calls
arranging for replacement parts, and had one of the techs waiting at the
airport for them to arrive after losing audio on every satellite
delivered channel on a CATV system because o the manager's attitude of,
'It's just audio, why waste money on shielded cable'? The <$20 he saved
caused us to spend over $1000 to repair.
Our satcom antennas in domes atop military aircraft were protected
What did you use as a reference manual for antenna grounding? My home
antenna mast is next to a granite outcrop that keeps me from
installing the multiple radials I'd like to have.
Thee were no grounding manuals availabe to the CATV industry, so I
used common sense to protect the equipment. Three, 24 ground rods were
driven through the concrete floor for the modulator/processor/computer
racks. Then the racks were lifted over the new ground rods to put them
inside the racks. 8AWG bare copper was welded to the rods, then to the
racks. The paint was ground off the insides of the racks at each bolt
hole, and a star lockwashers were added under each nut and bolt head. At
least eight bolts where each rack joined the next. ALL audio wring was
replaced with Belden two conductor shielded cable, and run in 3" Panduit
ducting, with new double shielded video cable. The original cabling was
run loose over the ceiling tiles, which presented more area to act as
antennas. Since the opening in the Panduit ducting faced the floor, I
used pencils every foot to hold the wires up, until I was ready to
install the covers. I simply slipped them into the open slots, and let
the ducking hold them in place. Once the covers were on, they were
pulled out to make it difficult for anyone to cover up their tampering. :)
A spare 19" aluminum 2U rack panel was drilled for F61 double female
'F' connectors, and used for a bulk grounding plate for the TV antennas
right after they enered the building. That was tied to the 24' ground
rod behind the C-band racks.
After that rebuild, we had no more problems. It had to be done this
way, because we couldn't simply shut down 10,000+ TVs while we made
repairs and did upgrades. I also had to replace the CA3240 CMOS input
Opamps in every modulator, as part of the repairs. I had all 36 channels
working in under 19 hours, which was at noon on a Saturday.
This all happened in 1982.
Now thanks to the Net we have almost too much information, some hard
to find or conflicting:
At Mitre I was reorganized from a digital communications department to
a radio one, of which I knew almost nothing. The company accommodated
us transferees by having a retired British radar boffin teach the
amateur radio class. In return we helped him maintain his extensive
home installation. I was the ground-level assistant to the tower
He didn't have an elevator on his tower? :)
That website is written by ham radio types, not engineers. A lot of
it is rule of thumb, and old wives tales.
Motorola has some hard rules about prepping a site for their
equipment, but I haven't seen it. I se it mentioned on a Facebook group
for Broadcast Engineers.
The last tower site I worked at was 1700 feet. It had antennas for
two TV stations, five FM stations and a lot of trunking radio systems.
The trunking radios were put out of business by cell phones.
My first visit to the station was on a cloudy night. Part of the
tower was hidden by the clouds.
They hired an expert in RF system design from a college, since it was
their first 'Million Dollar Headend'. It looked like it was laid out by
a drunken teenager who had only seen an I-pad.
The room had it's own air conditioning, yet equipment was
overheating. The audio and video wiring was crap, and anything as
grounded, other than through their power cords or several hundred feet
of RG6/U, and then through 130 feet of tower.
I moved all the racks slightly, and some of the equipment
temperature dropped by over 40 degrees. Some of the moves were for the
improved grounding, while the others were done to improve airflow.
The 'man' who replaced the designer was even worse. He was the one
who hired me, and he bragged about all of the stupid things he'd done at
other CATV systems, including how many bucket trucks that he'd wrecked.
His name was 'Bliss', and he was an idiot. He would set the video levels
without terminating the waveform monitor. The Collins had 4 Volt
unterminated output, instead of the 1 volt terminated that was industry
standard. He insisted that Tektronix knew nothing about video test
equipment, even though 95% of all video waveform monitors were built by
I also caught an overheating three phase power panel that he tried
to brush off as not important. That cost us a couple thousand dollars to
repair. The neutral was undersized for electronic loads, and the
harmonics had the wire too hot to touch. You could feel the heat, just
by walking past the panel.
He refused to replace the desiccant cartridges in the pressurization
system for the Heliax to the 5 meter dish. We ended up wit gallons of
green water inside that expense cable.
When they fired him for sexual harassment, they walked in a brand
new VP, with a new manager from our smallest systems. He pissed me off
by telling me that "Any service company would be proud to have our
work", so I gave two weeks notice. I spent part of my last week
installing all new C-band microwave equipment, because Collins/Rockwell
would no longer service it, and none of those service companies would
touch it. I routinely rebuilt the Collins equipment in house for our
system, and other systems owned by United Video.
My degree is in Chemistry, a very hands-on field in which you may not
have an assistant, so we learned the practice as well as the theory. I
haven't often seen the same from many recent electrical and mechanical
engineering graduates or the co-op undergrads I rode herd on. After
they left I redesigned their circuits with half the components, which
mattered when packed into a Xilinx chip.
I picked up a lot of practical knowledge from the manufacturers' data
sheets I studied to learn how to use their products. Switches and
fuses for instance aren't that simple if you need to push their
capabilities while expecting long life.
One young engineer kept asking me for Polaroid scope camera film by
the case, until I showed him that data sheet which answered all his
The 30A output breaker on my welding transformer power supply can hold
70A for a few seconds, to quickly measure diode drop etc. At 300A it's
rated to open but not necessarily to close ever again.
This guy was a professor who was teaching CATV system design. I
wrote a simple program in Basic for a Commodore 64 computer to calculate
cable loss, and the insertion loss of line taps. You could select any
brand of hardline, in any available size by the OEM part number, along
with the taps by their OEM numbers. You entered the source level, and
the amplifier gains, then the distance between taps, and the number of
ports at each tap. It also allowed multiple bridging outputs per trunk
amplifier, and to help decide which direction it was to be run from.
Sometimes it allowed you to eliminate an expensive line extender
amplifier. Every amplifier you could eliminate from the design reduced
the electrical load, and improved system reliability. The electric
company charged you for a full line load from each of the 60 VAC, 30A
modified square wave power transformers, rather than meter the power
input for each. They were ferro-resonant transformers made famous bu Sola.
It did the strand map information in seconds, that took this bozo
hours to do. The only assistant in this type of work was someone who
drew the actual maps that showed the location f the hardware on
existing, and private poles, or underground installs.
I designed an interconnect between two CATV systems for their
community loops, to provide a private system for the local schools. I
did all of the calculations, and calibrated the equipment before it was
installed. I was only off by .25 dB at the interconnect site, and they
entire system was in spec at initial turn-on.
I have close to 200 databooks in paper format, and thousands of
datasheets or databooks in PDF files here at home.
I found design errors in many older products at Microdyne, and came
close to being fired over it, several times because the older engineers
were furious that a tech had the nerve to point out a ten yer old mistake.
There is currently a thread on a Facebook group where someone used
two short SFE 32 VDC automotive fuses in series to replace a 3AG/AGC 250
volt fuse. The idiots think that it's cool, and or funny. those 32 volt
fuses will not open reliably at 250 volts. According to the long
standing data, the first to open will create a ball of plasma, and keep
conducting. The heat will destroy the fuseholder, and the fire can
spread into the wiring, and on to the surroundings.
I can't wait to see the gore and glory when a Millennial architect
gets together with a Millennial inspector, who then let a Millennial
contractor and Millennial carpenters and metalworkers build the
skyscraper. You thought you had it bad...
At least you were getting them from Polytechnic colleges. We had a
new teacher fill in for another at Coleman College when I was learning
about trons. He had been an English teacher and was now teaching
Computer Electronics Technology. I thought that rather odd, and knew
(and found) that I couldn't ask him any tech questions. I believe the
Teacher's Union Industrial Complex have a "teaching algorithm" which,
in theory, allows any graduate to teach anything in a matter of weeks.
Marry that to even more Post-Modernist/Feminist/Progressive thinking
and you have what's teaching (and coming out of) Uni these days.
That's the correct way. We knuckle busters installed circuit breakers
in cars with hi-power stereos because transient currents could and
would break normal fusing. That was before they were running enough
amperage and speakerage to blow the hatches half an inch off their
seals. I can't imagine the overpressure in the vehicle, matched with
the decibels of the Rap (which I still refuse to call "music") does
their brains or bodies any good.
(facepalm) I imagine he found those as interesting as the paper
things we used to refer to as "manuals".
"What'll they think of next?"
I'd say that's most likely a good thing.
Do not let your fire go out, spark by irreplacable spark.
In the hopeless swamps of the not quite, the not yet, and
I read an automotive paper about vehicle suspension frequencies to
avoid because they could unpleasantly resonate internal organs. I
couldn't generate them at a high enough power level to notice
anything, although my stereo can rattle the doors and windows.
The heavy and flexible cable for car audio has been useful in my
alternate energy projects.
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