BNC T Connector???

Discussion in 'General Electronics Chat' started by spinnaker, Nov 14, 2009.

  1. spinnaker

    Thread Starter AAC Fanatic!

    Oct 29, 2009
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    Some of you may know I am reintroducing myself back to electronics after a 20+ year hiatus. I am going through my old junk box looking for usefull items.

    I found a BNC T connector. For the life of me I can't remember how I used this. I never owned a scope but used plenty of them back in the day at work. Somehow this connector wound up in my personal stash.

    I remember using them but can't remember how. How would I have used this thing?
     
  2. SgtWookie

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    Jul 17, 2007
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    Remember the old 10base 2 Ethernet cards? The coax connectors? You had to terminate the ends of the loop with 50 Ohm resistors, and in the middle of the loop, each Ethernet card used a T connector.
     
  3. SgtWookie

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    You might've also used a T connector if you were looking at filters or loads checking for S-parameters with a network analyzer.
     
  4. spinnaker

    Thread Starter AAC Fanatic!

    Oct 29, 2009
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    YES! That was where it was from. Oh those were the days.

    I can't remember the name of the one manufacture. Began with an E I think.


    I remember the horror story with the very first customer we installed. They were wondering why their files were being corrupted. I contacted the manufacturer and they told me the network is a "disk" server and not a "file server". It turns out each user had their own copy of the FAT. Whoever wrote last, that's whose FAT you got! To write you had to each have separate logical drives.


    And then there was the customer that made a diskcopy of Peachtree Accounting and wondered why her 10 Meg Davong hard drive (who on earth would ever need more than 10 Megs :D ) had suddenly become a 360K hard drive!


    And then there was the time I should up at a users location to repair their Tallgrass hard drive. I did not have the part to repair it so I told the customer I would have the part Fedexed and return in the morning. It was raining when I left. The next morning I called and called. No answer. Finally I got in touch with someone late in the afternoon. I told them I had the part and would stop by to repair their hard drive. She said don't bother, the computer because the computer had been under about 2 feet of water! She said about 20 minutes after I left the day before, they came in to rescue the whole office in canoes! Turns out the nearby creek flash flodded. :)
     
  5. SgtWookie

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    Those were the days where when someone bumped their computer with their foot, the network went down! :eek:

    I had an old IBM 3278 mainframe terminal on my desk; ancient $10,000 boat anchor. Our department manager tried like heck to get me off of it, and on to a PC for my mainframe work. I told him I would, just as soon as they demonstrated that the network had less than 5 minutes downtime in any month of the year.

    They never even got close; it usually crashed around 10AM on Friday, and everyone had to log into the timekeeping system using my dear old dumb terminal so they could get their paycheck the following week. This was about 17 years ago.

    You might be thinking of 3-Com? Those cards were around $200 each in the old days. They were HUGE, too; all populated with DIP chips, pull-down resistors, discrete components - nowadays they have just a single VLSI chip on the PCI cards.

    Nice! :D


    Oh, how fun...

    We had a secretary that was having problems with losing files on the 8" disks of a WANG word processor. Turned out that she was typing the labels out - after she put them on the disks; just rolled 'em right into the machine and hammered away! :rolleyes:

    We had a guy staple a note to a floppy disk.

    Had another guy stick a floppy to a white board with a magnet.

    I spent a day writing a simulation program for a fellow who had a Dr. degree in Physics; the next day he came to me and told me his computer wouldn't read the disk. Turns out he left the disk on his magnetic paperclip holder...

    Went over to the home of a fellow who was our resident EMF/EMP expert, with a masters in Physics. He had his collection of floppy disks for his computer stored with his old fashioned telephone - he certainly got a sheepish look when I asked him why he had a Ma Bell powered degaussing coil in with his prized collection of disks...

    One of those Deepwater hard drives, eh? ;)
     
  6. spinnaker

    Thread Starter AAC Fanatic!

    Oct 29, 2009
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    Yes 3COM. Good memory! :)





    Memory is fuzzy on this one, can't remember it was me or a fellow tech but there was a guy that had practically had his whole PC replaced. "Intermittent" problems with the floppy disk. He had yet another repair call an right before he has it repaired yet again. He takes the diskette out and puts it up on his file cabinet with a big magnet! :eek:

    And then there was the guy with PC memory issues. On separate calls, I replaced all of the memory, I replaced the system board. Still I got another call and I should up for another repair. He had Visicalc running so I go to exit it with /Q and Visicalc pops up! I /q again and it pops up again! He had visicalc loaded at least 3 times! He was starting visicalc, shelling to DOS then starting a whole new instance of visicalc, instead of exiting DOS.

    And then there was one of my most genius moments in my career. We had a customer with a Tallgrass harddrive. In those days you had to boot them via the floppy. Every week or so I would get a call that he could not boot his PC. I replaced just about everything but got another call. I was trying to talk hom through some things over the phone. He mentioned how cold it was in the office. A light went on in my head. I remembered reading how when people got diskettes in the mail during the winter, they would not work at first. I told him to take the diskette to a warm office for several minutes then come back and try again. Sure enough it worked!

    I used to carry a whole pile of those old diskette drive doors in my tool box. They would break all the time. I used to wonder why until I saw a customer open the drive door and practically lift the PC off of the desk!

    I remember repairing one at one customer's office. I noticed a pair of glasses on top of the file cabinet. A note attached that said "Found yesterday in the gym". Several months go by and another repair (for all I remember another drive door :) ). There were those same pair of glasses on that file cabinet with a note "Found yesterday in the gym". I thought, "that darn kid must lose his glasses every single day"! Just my warped sense of humor. :)
     
  7. someonesdad

    Senior Member

    Jul 7, 2009
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    Earlier this year I sold an HP 9817 computer that I bought around 1985. It had been sitting in a cabinet for a couple of decades or more. I was a bit amazed to get it out, connect the thing up, and fire it up. It worked! It had a 10 MB hard drive in it. And people really did think 10 MB was far beyond what they ever would need.

    This hard drive was one of the first 3.5" SCSI disk drives on the market (if not the first). I sold the computer and disk drive for $2000 -- and the gentleman who bought it was only interested in the disk drive (as part of a legacy test system). I had worked on the thin film disk team at HP that made the disks in those drives and a couple of years later I returned to that group to be the thin film engineer in the group that sputtered the thin film coating on those disks. We had worried a lot about stiction between the head and disk in those drives, causing a failure of the drive. If any of you old MRTC or Nighthawk employees are reading this, the drive worked! :)
     
  8. SgtWookie

    Expert

    Jul 17, 2007
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    I bought a TRS-80 Model I computer about the 1977-1978 timeframe. It had a Z80 microprocessor running at a blazing 1.77MHz. It had 4k RAM, 4K ROM containing Level I Basic, a gutted RCA B&W TV painted in Chrysler Silver as a monitor (as supplied by Radio Shack), a cassette deck to store programs/data on, and a "wall wart" type power supply, all for $630 out the door.

    Upping the stakes to 16k RAM, 16K ROM w/Level II Basic and a numeric keypad raised the tab another $179.

    It didn't have lowercase installed when I got it. I bought one of Dennis Bathory Kits' books on the TRS-80, and installed a lowercase mod "dead bug" style, and had to write an assembler code driver to enable it.

    I later added an expansion interface from a company called Lobo Drives out in Goleta, CA for $450, expanded the memory to a whopping 48K! Added on three BASF 5-1/4" DSDD floppy drives to the tune of $210 each; for 174k of storage per disk. About the same time (1980) I looked into the latest technology; Winchester HDD's. A 5MB drive was available for a mere $9,999!! :eek:

    A few years later, I was in a computer salvage shop; they were using 5MB drives as door stops and paperweights. ;)
     
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