Some not so quick... quick and easy Christmas presents.

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.

Reply to
Michael A Terrell
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Now thanks to the Net we have almost too much information, some hard to find or conflicting:

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"are-fifty-six-man-2005.pdf" ???

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 climber.

-jsw

Reply to
Jim Wilkins

I know, I know ---"No brag, Just fact"

Reply to
Tom Gardner

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.

Reply to
Michael A Terrell

I bet. The stainless steel "tactical" pens are selling for $20 to $50 on Fleabay. The way I made these there is no way I could afford to sell them that cheap. I did think about it though. If I made a couple sets of soft jaws for the Hurco I could do 8-10 at a time doing everything except the internal threading of the cap, and the finish taper and grip lines of the body. Then finishing them on the lathe would be much quicker. I suppose I could sit down and figure otu the speed and feed for my tapping head to do the internal threads too, but that would be fiddly and time consuming to get just right to not jerk the pens out of the vise and not break the taps on the retract without constantly clicking the head.

Reply to
Bob La Londe

Ya gotta love "upper" management, don't ya?

Reply to
Larry Jaques

Did I just hear little Gunner's little friend, Tristy, say "Ground it to the gas pipe."?

Reply to
Larry Jaques

Wow, the monthly electric bill for all that must have been staggering.

Looks like some of my sister's emails. She uses Google Voice to Text convertor.

And proud to be on the ground, no doubt?

Reply to
Larry Jaques

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 them.

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.

Reply to
Michael A Terrell

I think it's a romantic thing. Like dipping Gunner's pigtails in the inkwell. And in return, Gunner should dip his something in the something.

Reply to
Tom Gardner

Face it, he's got a crush on you! Kinmda' makes your but tingle...don't it?

Reply to
Tom Gardner

We all know the reason..."Hot monkey love!" Why else would you want pictures of Gunner's crotch?

Reply to
Tom Gardner

Cuz' most people agree with Gunner, you should cease to exist!

Reply to
Tom Gardner

Not worth fuel for the backhoe,

Reply to
Tom Gardner

Full traction in what? Don't you get it? Nobody even likes you a little! At least Gunner is lovable. I'd hire half a Gunner over a dozen of you!

Reply to
Tom Gardner

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.

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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.

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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 questions.

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.

-jsw

Reply to
Jim Wilkins

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.

Reply to
Michael A Terrell

One of the "Here, hold my beer and watch this. I is a Injuneer!" types, eh?

Good for you.

Reply to
Larry Jaques

No, it was more like, 'They hired me to run this place, and you just want to spend money.' One year they announced that due to the purchase of a large competitor, there would be no bonus checks that year, except for the managers. He was waving a ?$50 check in our faces as another check fell out of the Fedex envelope. It had my name on it. He laughed and said, If I only got $50, your check must just be $5. I opened it and said, You're right. it is $500.00. Mine was ten times what he got, because of the extra time that I put in, and the money that I had saved the company.

Reply to
Michael A Terrell

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.

Reply to
Larry Jaques

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