02-24-15 16:42 Damon A. Getsman wrote to Ed Vance about Re: Using AX.25 w/older   
   h   
      
    DAG> @MSGID: <54EDB492.754.amtradio@capcity2.synchro.net>   
    DAG>   Re: Using AX.25 packet w/olde   
    DAG>   By: Ed Vance to Damon A. Getsman on Mon Feb 23 2015 12:20:00   
   Howdy! Damon,   
      
    EV> My only experience with Packet on Ham Radio was by using Digicom with   
    EV> a circuit connected to my Commodore 64 pc's Cassette Port.   
      
    DAG>   Whoa.  I should've been doing that with my Atari.  Alas, my   
    DAG> cassette port was hooked up solely for data storage for a long   
    DAG> time.   
      
   Probably there was some software/hardware like Digicom for the Atari,   
   Don't know, Digicom afaik was for use with a C=64.   
      
    EV> The Ham that helped me get started in Packet used a TNC and the Baycom   
    EV> program on his 386 pc.   
      
    DAG>   Nice.  I had a friend back in Jr. High, about when 386 was   
    DAG> the big thing, that was working with a much more archaic system   
    DAG> for packet radio.  Thing was, at the time I never really   
    DAG> understood what he was up to.  Wish I would've paid more   
    DAG> attention to him now.  :P  I was still online with my Atari   
      
   We all learn a little bit at a time, don't we?   
      
    DAG> 130xe at that time (I'd finally graduated from a tape drive up   
    DAG> to a 180k disk drive), just starting to learn how to use a   
    DAG> modem and really getting into it.   
      
   I got the C=64, Floppy Drive and 300 baud Modem to start out with.   
   I've seen how slow Tape transfers were and didn't want that, I wanted   
   the FDD even though it was very costly back in 1984.   
      
    EV> I know that doesn't help You any with OpenBSD but I just had to make   
    EV> a comment here in case no one else was trying to help You.   
      
    DAG>   No worries.  I'm interested in the full history of things   
    DAG> now.  I missed out on a lot of opportunities to learn about   
    DAG> this now; I value the background you're giving me and   
    DAG> appreciate it.  :)   
      
   I just know pieces and bits, and had help learning what I learned from   
   some other Hams who took their time explaining what's what to me.   
      
    EV> Before I ran Packet, I used a Netronics ASCII/Video board with their   
    EV> Keyboard connected to a 555 Audio Oscillator circuit going to the Mike   
    EV> Connector of either my 2M VHF FM rig or my HF SSB rig, and a circuit   
    EV> for a RTTY Demodulator that I found in a Popular Electronics magazine   
    EV> that was connected to the Earphone Jack of either rig.   
      
    DAG>   Well.  Were you just copying the schematics at that   
    DAG> point or did you have a bit of the understanding of the   
    DAG> electronics theory going on behind that? I've been waiting   
      
   This was back in the Mid-1970's when I assembled that stuff.   
      
   I saw the 555 AFSK schematic somewhere, just as I copied the portion   
   of the RTTY Reader project in PE Magazine.   
   That Reader had maybe eight LED's on the front panel, that scrolled the   
   words in the RTTY signal data.   
   Can't remember if they were regular 7 Segment LED chips or what.   
   Some letters in our alphabet would be hard to configure on a 7 segment   
   display chip, I'd think.   
      
    DAG> to delve back into electronics; I've got a few high voltage   
    DAG> plans that I've had slated for years now, and have just within   
    DAG> the past year gotten the parts for.  Unfortunately, right when   
    DAG> I was starting work on them, and a fresnel lens oven/omg lazer   
    DAG> of death, my stability got blown out of the water.  Had to   
    DAG> leave most of my equipment and materials behind.  Still working   
    DAG> on getting on my feet again; hopefully it happens soon so that   
    DAG> I can have fun lightning to play with again.  Heh.   
      
   When You get back into doing that High Voltage stuff be very very   
   careful and don't let it 'talk' to You.   
      
    EV> I had 10 turn POTS to make Audio Frequency changes to the Demodulator   
    EV> Mark and Space settings that I used for RTTY on VHF so I could change   
    EV> it when I used it on the HF rig.   
      
    DAG>   This is good info.  I shouldn't be surprised, but I'd not   
    DAG> heard of the 10 turn pots before.  I can see how that would be   
    DAG> a very good thing in such an application.   
      
   I got those POTS from a Ham who salvaged surplus military electronics   
   to get the parts from them.   
      
   Those two 10 Turn POTS came with a calibrated dial that could be locked   
   to keep it from moving.   
      
   They are called "Helipots".   
      
    EV> I had two POTS on the 555 circuit board to adjust the Mark and Space   
    EV> settings for either VHF or HF use.   
    EV> I used the Standard Mark and Space frequencies when I was on the 2M rig   
    EV> but learned that I could use my own frequency settings on the HF SSB rig.   
      
    DAG>   This is all stuff that I need to learn more about.  I've got   
    DAG> some manuals downloaded for the test, I'm assuming that the   
    DAG> info about the protocols and what these are used for will be in   
    DAG> there somewhere...   
      
   The VEC Test Question Pool can be downloaded from http://www.ncvec.org   
   if You want to study them.   
      
    EV> After I built the circuits I tuned my HF radio to the frequency that   
    EV> W1AW's RTTY broadcasts were made on.   
    EV> When the broadcast started I turned the Mark POT on my Demodulator to   
    EV> get the Mark LED blinking, and did the same for the Space POT until   
    EV> I could see the broadcast plainly on my TV Set.   
      
    DAG>   Interesting...  You're kind of losing me here..  I wasn't   
    DAG> aware you were speaking of video capability.  SSTV is all I've   
    DAG> heard about as far as that so far, and from what I've heard   
      
   Yes, I wrote about the Netronics ASCII/Video board kit earlier.   
   It was meant to be a Terminal with RS-232 output.   
   I just grabbed my connections a little upstream of the output where it   
   was TTL level.   
   That's how I was able to connect the AFSK Keyer and Demodulator to   
   the Netronics kit.   
      
   What got me interested was I had read a book called the TV Typewriter   
   Cookbook and it interested me because someone could get on RTTY without   
   having the noise and buying paper for it.   
   I used a cassette recorder to record the receiver audio as I was   
   reading what was coming on the screen, so I could play it back to see   
   it later on, if I wanted to.   
      
    DAG> it's a trickle over packet...  So I'm assuming you're talking   
    DAG> more about a live analog modulated signal rather than AX.25...   
      
   Yes, as long as the difference in the Mark and Space frequencies were   
   170 Cycles apart, my configuration worked like "Duck Soup".   
      
    DAG> Please correct me if I'm wrong here.  I'm obviously not getting   
    DAG> something right, as the demodulator would indicate that there   
    DAG> is digital transmission going on here, and everything I've ever   
    DAG> seen with 'TTY' in it has to do with slow rate data   
    DAG> transmission of an ascii variety...   
      
   I could operate at 60 & 100 WPM Baudot, and 110 WPM ASCII.   
   Never could get 300 WPM ASCII to work with my stuff.   
      
    EV> After the broadcast was over, and before I keyed the transmitter to   
    EV> send a CQ, I turned the POTS on the 555 circuit - while either pressing   
    EV> my telegraph key or releasing it - to get the LEDs on the Demodulator   
    EV> to light up.   
      
    DAG>   What were you transmitting there?   
      
   I wasn't transmitting yet, I was just adjusting the AFSK Keyer's Audio   
   to match what the RTTY audio signal I just heard coming out of my SSB   
   rig.   
      
    EV> Then I keyed up the HF rig and typed CQ on that frequency and another   
    EV> station answered me.   
    EV> That is how I had my first RTTY QSO.   
      
    DAG>   Interesting...  This bit of the protocol on things is very   
    DAG> helpful for me, I've never been around someone doing this live,   
    DAG> so this is all very new to me. Please forgive, again, my   
    DAG> ignorance and probably blatantly gumshoe questions here.  ;)   
      
   Hey!, Anyone who know me, knows that I'm ignorant about lots of stuff.   
   I learned by asking questions, everybody does, unless they are inventing   
   something new that's never been done before.   
      
    EV> I'm not familiar with that rig, sorry can't help You with that.   
    EV> Although I know National made some very fine equipment.   
      
    DAG>   No worries.  If you're talking about data over the equipment   
    DAG> you were using, I'm pretty sure that the one I'm looking at,   
    DAG> while perhaps not made for it, can be induced to transmit my   
    DAG> AX.25...  Though for OpenBSD I'm pretty sure I'll need some   
    DAG> sort of hardware interface to the modem aspect of things.   
      
   Everything I've been talking about pertaining to RTTY has been about   
   AUDIO.   
   The Digicom stuff I used later when I got the C=64 converted Audio to   
   Data on the cassette port, and Data from the cassette port that I typed   
   on the C=64 keyboard into Audio.   
   -snip-   
    EV> Years later I got a used Hallicrafter SX-42 for my shack.   
    EV> 73 and wish You well with what You choose.   
      
    DAG>   Well thank you very muchly.  I really appreciate the look   
    DAG> you're giving me into the hobby that I'm working on getting   
    DAG> into.  No doubt the first rig I get is going to be something   
    DAG> that will be replaced in the future, but I'm actually kind of   
    DAG> keen on the idea of having an analog box with replaceable   
    DAG> relays... Vacuum tubes would be great (for everything but the   
    DAG> power bill), but I'm not going to hold my breath on that bit.   
    DAG> ;)  I'm trying to save money, not spend more of it.   
    DAG>   Best wishes!   
      
   There are many things that Hams are interested in, I've only done a   
   tiny bit if what Hams do.   
   But what I do I enjoy, You will enjoy it too, just only put one hand   
   in the final amplifier, keep the other one in your pocket.     
   73   
      
   ... I to.d yo., "Never.touch .he flo.py di.k su.face!"   
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