Question on AC grounding - found an old device that has me confused

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  • EasyGoing1
    Shock Therapist
    • Sep 2016
    • 977
    • USA

    #21
    Re: Question on AC grounding - found an old device that has me confused

    Originally posted by Per Hansson
    -But ohh, what if the customer don't have a grounded outlet?
    Well that's his fucking problem then, isn't it?
    Seriously, how old of a building would you have to be in to not have a ground in your AC outlet? I'm thinking pre-1950's?
    sigpic

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    • EasyGoing1
      Shock Therapist
      • Sep 2016
      • 977
      • USA

      #22
      Re: Question on AC grounding - found an old device that has me confused

      Originally posted by eccerr0r
      I didn't think RatShak was so bad to sell (under their name) things that could kill people
      To be fair, I did not see a Radio Shack brand on this device nor the other brand that they manufactured and sold under ... was it Realistic? I know Tandy was their computer line ... I can't remember ... but there was no branding on this thing at all, it just LOOKED like a device that Radio Shack would make and sell back in the day.

      sigpic

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      • stj
        Great Sage 齊天大聖
        • Dec 2009
        • 30977
        • Albion

        #23
        Re: Question on AC grounding - found an old device that has me confused

        if it isnt branded, radio shack didnt sell it.
        maybe it came from a cable company or with some security camera stuff
        it's too solidly build to be from a computer/games company.

        the construction reminds me of old General Instrument (GI) cable boxes.
        Last edited by stj; 02-21-2021, 05:26 AM.

        Comment

        • televizora
          ghettomodmaster
          • Nov 2016
          • 957
          • Bulgaria

          #24
          Re: Question on AC grounding - found an old device that has me confused

          Originally posted by eccerr0r
          They still make 2-prong extension cords and three conductor cords are less physically flexible and heavier than two conductor cords.
          These are only excuses. The weight matters only in USA. For example, our outlets and extension cords are exclusively Shucko /Well, sometimes Europlug can be seen for smaller devices/. Nobody will connect the chassis to mains and use one pin of the Europlug as ground, hoping that he will not electrocute somebody. It is a well known fact that US outlets and plugs are notoriously unsafe, excuse me, but this is the truth. Not only this, but the socket itself does not provide any support for the plug and the plug can just pop out of the wall. With guiding notches and recesses many other types of plugs and sockets eliminated this flaw. I have to say that the stupidity, seen on the pictures in the first post combined with not so well designed sockets and plugs represent shock hazard. I fail to understand how this box passed any certification at all. If it was me to certify it, I would just throw it out of the window.
          I also have to underline that if you used your plugs and sockets with 230V, there would be dead people, for sure. Some of us even have 380V in our homes, for larger kitchen appliances or instant water heaters.
          Boxes and other stuff should be Class II appliances - double insulated. Otherwise adequate grounding means MUST be provided.
          There should be no way for mains to be able to get onto the chassis.
          Last edited by televizora; 02-21-2021, 06:42 AM.
          Useful conversions. I don't "speak" imperial. Please use metric, if you want to address me.
          1km=1000m=100000cm, 1inch=2.54cm, 1mile=1609.344meters, 1ft=30.48cm 1gal(US)=3.785liters, 1lb=453grams, 1oz=28.34grams

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          • EasyGoing1
            Shock Therapist
            • Sep 2016
            • 977
            • USA

            #25
            Re: Question on AC grounding - found an old device that has me confused

            Originally posted by stj
            the construction reminds me of old General Instrument (GI) cable boxes.
            I remember them ... didn't they make the first cable tv decoder boxes for pay channels?
            sigpic

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            • stj
              Great Sage 齊天大聖
              • Dec 2009
              • 30977
              • Albion

              #26
              Re: Question on AC grounding - found an old device that has me confused

              exactly, they said "Jerrold" on the front and had a 2 digit display and a keypad ontop.
              (and spied on your viewing using a return channel!)

              Comment

              • EasyGoing1
                Shock Therapist
                • Sep 2016
                • 977
                • USA

                #27
                Re: Question on AC grounding - found an old device that has me confused

                Originally posted by stj
                exactly, they said "Jerrold" on the front and had a 2 digit display and a keypad ontop.
                (and spied on your viewing using a return channel!)
                YUP! I remember!

                Before they had any kind of digital decoders, they use to put these filters out on the telephone pole where the cable came into the property that would actively filter out HBO if you didn't pay for it.

                Well, my brother - being the resourceful guy that he was ... got a ladder to get himself to the first pegs on the pole, then he went up the pole and remove the filter - he had to cut a section out of a socket because they had the nuts inside a sleeve around the coax making it impossible to loosen it without the "special tool" so he just sliced off part of a socket and that did the trick.

                When he got it off the pole, he opened it up and gutted it and connected both sides with straight coax and then put it back on the pole, that way if they ever came by to inspect, it would look as if the filter was still on.

                He was maybe 13 years old when he did that.

                We got free HBO for a long time on that little venture.. lol
                sigpic

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                • stj
                  Great Sage 齊天大聖
                  • Dec 2009
                  • 30977
                  • Albion

                  #28
                  Re: Question on AC grounding - found an old device that has me confused

                  we hacked the jerrold's too - a pic chip fitted to enable all channels and throwing the return "modem" in the trash.
                  not on the supplied box obviously - on a second (or 3rd or fourth! ) picked up used.

                  Comment

                  • EasyGoing1
                    Shock Therapist
                    • Sep 2016
                    • 977
                    • USA

                    #29
                    Re: Question on AC grounding - found an old device that has me confused

                    Originally posted by stj
                    we hacked the jerrold's too - a pic chip fitted to enable all channels and throwing the return "modem" in the trash.
                    not on the supplied box obviously - on a second (or 3rd or fourth! ) picked up used.
                    in the mid-2000's I was working for the local city as their network admin, and this new guy that we hired as a tech had just graduated with a bachelor degree in programming - though degree to get as it requires calculus and engineering physics ... so this guy was your a-typical propeller head ...

                    He took an original Pentium based clone PCs because it cost him nothing and in one of the drive slots where you would normally mount a CD / DVD drive, he had this custom made socket that attached to a PCI card via a ribbon cable on the motherboard and in that slot was a card -about the size of a PCM/CIA card and on the front of it was another ribbon cable attached to a credit card the was exactly the size of the thin plastic key cards that you insert into a satellite receiver to activate your satellite subscription.

                    Running on the PC was a custom operating system that somehow read signals from the card in the sat receiver and ran algorithms that could hack the signal and program the receiver to decode it.

                    Free satellite TV ... until they completely re-worked those scrambling signals making that pirate method null and void ... I don't remember if he ever took it to the next level or if it was even possible to descramble after the networks upgrade but it was quite an interesting project and certainly a hell of lot more complicated than 20 years prior when we just gutted a box and ran coax through it..
                    sigpic

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                    • stj
                      Great Sage 齊天大聖
                      • Dec 2009
                      • 30977
                      • Albion

                      #30
                      Re: Question on AC grounding - found an old device that has me confused

                      the tv card hack was very well known in europe,
                      it was dos software called "voyager"
                      it linked over a com port and a level shifter.

                      Comment

                      • EasyGoing1
                        Shock Therapist
                        • Sep 2016
                        • 977
                        • USA

                        #31
                        Re: Question on AC grounding - found an old device that has me confused

                        Originally posted by stj
                        the tv card hack was very well known in europe,
                        it was dos software called "voyager"
                        it linked over a com port and a level shifter.
                        I'm wondering now if maybe that setup read the satellite signal from the back of the PCI card - might have even been an ISA card (like with its own LNB connection), then it would just configure the credit card key in the sat receiver with whatever it needed to know to decode the signal.

                        Do you recall how that setup worked? His was the only one that I had any knowledge of ... though I'm sure they were advertised heavily in the hobbyist electronics periodicals. My brother used to subscribe to one of those magazines, though I can't remember for the life of me what it was called. It was very popular though ... maybe even called Popular Electronics? Or ... something like that...
                        sigpic

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                        • dmill89
                          Badcaps Legend
                          • Dec 2011
                          • 2534
                          • USA

                          #32
                          Re: Question on AC grounding - found an old device that has me confused

                          Originally posted by EasyGoing1
                          Seriously, how old of a building would you have to be in to not have a ground in your AC outlet? I'm thinking pre-1950's?
                          More like pre-1970s, grounding started to appear in the 1960s but didn't become universal in the US until the early 1970s.

                          Grounding of receptacles first appeared in the 1962 NEC (National Electric Code), but not all states/jurisdictions adopt the code updates at the same time so there can often be a decade or more from the time something new appears in the code until every state/county/city actually implements the updates (for example today some States are still on the 2008 revision of the NEC). https://na.bhs1.com/state-by-state-g...-nec-adoption/


                          Of course it is also common for people to (illegally) swap out 2 prong outlets with 3 prong ones without actually adding grounding (there is a legal way to do this with a GFCI and stickers indicating "no equipment ground" but many don't to this).
                          Last edited by dmill89; 03-08-2021, 07:17 PM.

                          Comment

                          • stj
                            Great Sage 齊天大聖
                            • Dec 2009
                            • 30977
                            • Albion

                            #33
                            Re: Question on AC grounding - found an old device that has me confused

                            i know exactly how it worked, i had sourcecode.
                            the card contains a microcontroller and the contacts are a serial port,

                            the pc just simulates the microcontroller.

                            the way it works is the decoder tells the card the channel ID, and a cypher key that is encrypted.
                            the card then checks the channel ID against a table of what you subscribed to, and if the ID is in the table it decrypts the key and returns it to the box to decode the stream.

                            where we are now, is the latest boxes run Linux with the card emu onboard and can get the key data over the net in realtime.
                            https://github.com/gfto/oscam
                            Last edited by stj; 03-08-2021, 07:18 PM.

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