Announcement

Collapse

Forum Rules and Etiquette

Our mission ...

This forum is part of our mission to promote the preservation of vintage computers through education and outreach. (In real life we also run events and have a museum.) We encourage you to join us, participate, share your knowledge, and enjoy.

This forum has been around in this format for over 15 years. These rules and guidelines help us maintain a healthy and active community, and we moderate the forum to keep things on track. Please familiarize yourself with these rules and guidelines.


Rule 1: Remain civil and respectful

There are several hundred people who actively participate here. People come from all different backgrounds and will have different ways of seeing things. You will not agree with everything you read here. Back-and-forth discussions are fine but do not cross the line into rude or disrespectful behavior.

Conduct yourself as you would at any other place where people come together in person to discuss their hobby. If you wouldn't say something to somebody in person, then you probably should not be writing it here.

This should be obvious but, just in case: profanity, threats, slurs against any group (sexual, racial, gender, etc.) will not be tolerated.


Rule 2: Stay close to the original topic being discussed
  • If you are starting a new thread choose a reasonable sub-forum to start your thread. (If you choose incorrectly don't worry, we can fix that.)
  • If you are responding to a thread, stay on topic - the original poster was trying to achieve something. You can always start a new thread instead of potentially "hijacking" an existing thread.



Rule 3: Contribute something meaningful

To put things in engineering terms, we value a high signal to noise ratio. Coming here should not be a waste of time.
  • This is not a chat room. If you are taking less than 30 seconds to make a post then you are probably doing something wrong. A post should be on topic, clear, and contribute something meaningful to the discussion. If people read your posts and feel that their time as been wasted, they will stop reading your posts. Worse yet, they will stop visiting and we'll lose their experience and contributions.
  • Do not bump threads.
  • Do not "necro-post" unless you are following up to a specific person on a specific thread. And even then, that person may have moved on. Just start a new thread for your related topic.
  • Use the Private Message system for posts that are targeted at a specific person.


Rule 4: "PM Sent!" messages (or, how to use the Private Message system)

This forum has a private message feature that we want people to use for messages that are not of general interest to other members.

In short, if you are going to reply to a thread and that reply is targeted to a specific individual and not of interest to anybody else (either now or in the future) then send a private message instead.

Here are some obvious examples of when you should not reply to a thread and use the PM system instead:
  • "PM Sent!": Do not tell the rest of us that you sent a PM ... the forum software will tell the other person that they have a PM waiting.
  • "How much is shipping to ....": This is a very specific and directed question that is not of interest to anybody else.


Why do we have this policy? Sending a "PM Sent!" type message basically wastes everybody else's time by making them having to scroll past a post in a thread that looks to be updated, when the update is not meaningful. And the person you are sending the PM to will be notified by the forum software that they have a message waiting for them. Look up at the top near the right edge where it says 'Notifications' ... if you have a PM waiting, it will tell you there.

Rule 5: Copyright and other legal issues

We are here to discuss vintage computing, so discussing software, books, and other intellectual property that is on-topic is fine. We don't want people using these forums to discuss or enable copyright violations or other things that are against the law; whether you agree with the law or not is irrelevant. Do not use our resources for something that is legally or morally questionable.

Our discussions here generally fall under "fair use." Telling people how to pirate a software title is an example of something that is not allowable here.


Reporting problematic posts

If you see spam, a wildly off-topic post, or something abusive or illegal please report the thread by clicking on the "Report Post" icon. (It looks like an exclamation point in a triangle and it is available under every post.) This send a notification to all of the moderators, so somebody will see it and deal with it.

If you are unsure you may consider sending a private message to a moderator instead.


New user moderation

New users are directly moderated so that we can weed spammers out early. This means that for your first 10 posts you will have some delay before they are seen. We understand this can be disruptive to the flow of conversation and we try to keep up with our new user moderation duties to avoid undue inconvenience. Please do not make duplicate posts, extra posts to bump your post count, or ask the moderators to expedite this process; 10 moderated posts will go by quickly.

New users also have a smaller personal message inbox limit and are rate limited when sending PMs to other users.


Other suggestions
  • Use Google, books, or other definitive sources. There is a lot of information out there.
  • Don't make people guess at what you are trying to say; we are not mind readers. Be clear and concise.
  • Spelling and grammar are not rated, but they do make a post easier to read.
See more
See less

Morse-Baudot

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    #16
    Originally posted by new_castle_j View Post
    I'm interested to learn how it operates, would it take an audio input from a HAM radio via the RCA jack and decode the dots and dashes? I don't know HAM radio, so wondering if someone else can take a more educated guess.[ATTACH=CONFIG]55678[/ATTACH]
    As G4UGM noted, no system for Decoding CW was fool-proof.
    Even when the other station was keyboard/computer sending CW (Morse), the QRN (atmospheric static) and QRM (interference from SW broadcast or other amateur radio stations) would result in gaps or “gibberish”.
    An appreciation & respect for the human ear/brain by Morse operators (military in WW2) increased in message reception.

    Today, amateur radio using dedicated DSP or the DSP chips within computer sound cards are using a variety of encoding methods (Protocols). JT65 was developed by Joe Taylor, K1JT (Princeton Physics)
    https://phy.princeton.edu/people/joseph-taylor
    for Earth-Moon-Earth (EME) communications — bouncing radio signal off moon’s surface.
    https://physics.princeton.edu/pulsar/K1JT/wsjtx.html

    Comment


      #17
      Wonderful, thank you for all the responses. Any guesses as to what the empty socket in the upper left of the board is for? The two chips to the left of the empty socket are ILD74, ILQ74 opto couplers. I'm guessing that this must be some kind of interface to transmit morse via a Ham radio. Perhaps it hooks up to a morse paddle key? The advertisement for this device also said that it can produce either TTY or CRT output, could that socket be some kind of hookup to a teletype?

      IMG_4176.jpg IMG_4177.jpg IMG_3.jpg

      Comment


        #18
        I think your right. It is likely a connection to something like a teletype. It would be worth tracing the leads out.
        I notice that the additional panel has two ribbon connectors on it. It also has lots of signal filters.
        Dwight

        Comment


          #19
          A little bit of progress, thanks to Jim Battle's SOL-20 emulator. I can load the ROM image from the Baudot board into the emulator and execute it. The ROM code relies on the SOL personality module (SOLOS) to provide the I/O routines. Starting the program is as easy as jumping to A000 and executing.

          When I execute it in the emulator, the copyright message displays, and under that "TTY" and a few seconds later the cursor starts flying back and forth and the screen begins scrolling. At any time I can type something in at the keyboard and it will pause and the letters I typed show up on the screen (only lower case, SHIFT key doesn't cause upper case letters on the screen), then it will go back to scrolling a couple seconds after I stop typing. I am guessing that this is the expected behavior, it seem like it just begins polling the Baudot board for an incoming stream of characters that would get re-directed to the screen. Perhaps typing in some characters interrupts the receive function and causes the board to transmit what was just typed. The ROM image didn't contain any ASCII strings in it other than the copyright message, no interactive menus or anything. I think the operation of this board is just that simple, plug it into your SOL, attach a Ham radio's audio out to the RCA jack, jump to A000, tune in a morse code transmission, and wait for some characters to display.

          Does anybody out there have a SOL-20 with SOLOS personality module, 40K of memory, a VDM-1 display board and a Ham radio? Would be neat to see if this thing works, PM me if you're interested in trying and making a video.

          Comment


            #20
            A little more progress... maybe. I was able to port the ROM on the Morse-Baudot board over to a COM file that is executable under CP/M. I could see the ROM code calling the SOLOS output routine while it was running in emulation and I patched in a routine to call CP/M's CONOUT instead. I tested in on real hardware and it runs, the copyright message displays when executed. Tonight I hooked up the Morse board to the audio out on my laptop, there's a website that you can type in a message and it will output a midi file of the morse equivalent. I fed that audio into the Morse board's RCA jack while the program running under CP/M and...... nothing happened. It was a long shot anyway.

            Comment


              #21
              Just more exploration to go through. I would assume you program produced a tone for the morse coded signal.
              Although, I'm sure the board is quite clever, it probably requires to be set to receive a particular rate.
              Dwight

              Comment


                #22
                Still messing around with this board, a little more research has turned up some useful information. The following advertisement points out the board's components. (this is the closest I can come to finding a manual). Also of note, the advertisement states: "Listen for these SYSTEM 4000 stations on the air: K60J0 is one mentioned on the list. My particular board has K60J0 written on one of the EPROMS and also those call letters are burned into the memory chip. I guess it's safe to say that this board was in use!

                Curtis1979.jpgCurtis1979-2.jpg

                Comment


                  #23
                  More good news, another advertisement confirms that a Sol-20 is not necessary to operate this board, it just needs console and I/O patches for any particular system. I've already got CONOUT patched, so perhaps I can work on CONIN. I've discovered a few "hot keys" that will print the call sign on the screen as well as the message "the quick brown fox jumps over the lazy dog" The adverts say that both baudot and Morse is supported, but I haven't figured out how to switch between the two decoding modes, so it's quite possible I've been sending Morse audio as input when it's expecting to receive Baudot. I'm having to learn about amateur radio in the process of playing with this board, lots of new vocabulary.

                  Jan-78.jpg

                  Comment


                    #24
                    Originally posted by new_castle_j View Post
                    More good news, another advertisement confirms that a Sol-20 is not necessary to operate this board, it just needs console and I/O patches for any particular system. I've already got CONOUT patched, so perhaps I can work on CONIN. I've discovered a few "hot keys" that will print the call sign on the screen as well as the message "the quick brown fox jumps over the lazy dog" The adverts say that both baudot and Morse is supported, but I haven't figured out how to switch between the two decoding modes, so it's quite possible I've been sending Morse audio as input when it's expecting to receive Baudot. I'm having to learn about amateur radio in the process of playing with this board, lots of new vocabulary.

                    [ATTACH=CONFIG]56218[/ATTACH]
                    You might want to ask about this board on the GreenKeys e-mail list. Its really a Teletype list but for HAMS. some one on there might have info, or if you like I can ask for you....
                    Dave
                    G4UGM

                    Looking for Analog Computers, Drum Plotters, and Graphics Terminals.

                    Comment


                      #25
                      Excellent idea, I've sent a posting to the GreenKeys list.

                      Comment

                      Working...
                      X