2011 DCC – INTRO to Digital DATA Modes

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2011 DCC – INTRO to Digital DATA Modes

welcome to ARVN amateur radio Video News the program you’re about to see is free to watch courtesy of YouTube thanks YouTube but it wasn’t free to make ARVNs got a lot of money invested in video equipment like this Swede camera and that editing system back there and it takes a lot of time to shoot and edit a program like this so I’m asking you to make a voluntary payment contribution whatever you want to call it just stop by our website ARVN TV and you’ll see a link to make that payment whatever you think the program is worth to you I guess you could say that this program is brought to you by you so thanks for watching and enjoy the show my name is george n 2 APB and i’ll be speaking today about digital modes this is an introduction to digital modes and as an introduction seminar and this is an hour and a half long I don’t know if it’ll go as long as an hour and a half we’ll see please let’s make this an interactive type of thing I suspect and and I target that you are here because you want to learn more about digital modes maybe you’ve not done it digital modes maybe you have tried it and had some difficulty and you’d like to get some tips and techniques you may you probably heard about psk31 but what about Hell schreiber or what about Thor what about mtor packet up packed or there’s a lot there and in what I’ll do and well target this toward is kind of a broad range of the technology give you a bit of a sense for what’s out there we’ll listen to some sound samples here and at the end of the presentation I’ll be able to use some of the software on here I’ve got some pre-recorded digital mode communications that I can pump in there and we can actually see how some of the software works specifically FL digi and digi pan which happened to be my two favorite programs and you’ll get a bit of a feel maybe how you can do this at home fairly easily I’ve always I mentioned this yesterday in the talks I’ve always been a a CW guy true and true I kind of goes with a qrp nature in the building it’s easy to build a CW Reagan and it’s just more gratifying to me to build something and put it on the air so I most of my life I’ve been a CW guy hardly know what a microphone is and hence hardly know what up and SSB rig is okay did you use it with a microphone I think so but when it comes to digital mode i said wow this is a really cool and I love boat anchors too I’m really really into a boat anchor so here we’ve got a guy who built a you know this little moan the digital modem and DSP technology and advanced you know kind of leading edge stuff in one world but still boat anchors and the other I’m looking to see how that can converge and digital mode is is perhaps one way that it can because digital mode is technology that uses SSB but not necessarily a microphone so that may be kind of happy and it can be used with an SSB radio doesn’t have to be a new fancy fangled you know 15 mode handheld submersible thing oh that is a nice rig that they have as a grand prize today for tonight’s banquet but it can be used on any kind of an SSB rig a little bit of stability as necessary as well we’ll see but it opened up in alas oh I don’t know maybe seven eight years it really opened up my particular hobby you know like I was enjoying myself but now there’s like an entire new aspect of the hobby and that’s a bit of the excitement that I wanted to convey with you here today so if it’s this is too basic the the presentation next store about how to use which which mode to use an emergency communications that might be okay but we’re going to go through some some six here so I’m going to talk about again what just what is digital communications again you might have heard a lot about it but not really understood you know now what it is at its heart its modulation and demodulation and then a happy ending with a contact or two we’re going to survey some digital modes there’s a boatload of information on the website on the Internet of course and I’m hoping

that maybe you’ll go on and look at some of the links and I’ve got at the end of the slide deck you’ll be able to see a lot of examples and a lot of people’s successes that they’ve done and building the interfaces in contact making different contacts because each mode tends to be have its own kind of specialty and characteristics some are good for super low power communications and reliable in noise some are have error recovery and hence or error correction and hence have absolutely perfect transmission and reception others are designed for communications just just typing as you would like on the Internet in a chat or on your on your phone conversational mode is what they call it others are picture oriented they just transfer transmit and then receive bitmaps essentially that are representative of the information being transferred he’ll Schreiber is a good example of that and when we’ll see some of these things and and if you’re is ins your city here in maybes because when you’re tuning across the band at any given time and you hear a lot of stuff on there alotta especially if you go a little bit off the beaten path you hear a lot of different kind of tones and Biebs and warbles and and you know you know you probably have a feeling that it’s digital mode but you don’t really know and man and after a while believe it or not just start to identify what it is and then you can do what it takes in order to receive it and you’d be surprised sometimes then the thing that’s always been a Bugaboo with me and with everybody that that I deal with again Joe and I deal with the n2 CX and I deal a lot with New Jersey club and beginners and Boy Scouts and kids in the church group and so on and they like to get into these things and we enjoy kind of instructing them and on how to build and how to make small circuits when it comes time to interface into the pc it’s a bear I mean what could be simpler plug in a cable in or two cables into your PC and you’re off and running well it’s really not all that straightforward there’s some hidden hidden sand traps and tar pits and you name it I saw some chuckles in the audience here so you might know what I’m talking about things like interrupts and and the proper version of drivers and interoperability of the components and which application works on your laptop which you got to put in the work station and so i’m going to i’m going to show you what my secret sauce is i’m going to show you what i would recommend a 22 a boy scout girl scout sitting in the audience here looking to try digital mode for the first time and it’s worked for me it’s worked for our club members and maybe you’ll be able to take some tips from this all right any any questions before we get started as far as like you know what my agenda is and the approach and is there anything that you’d like me to concentrate on is there some particular thing I was somebody that was sitting back over there where Scotty was said am I going to talk about em dr i was that you somebody asked a question if you’ve got a favorite mode or a mode that you’ve heard about or your friend told you about that you’d like to hear a little bit more about we’ll talk about it chances are i can pretty quickly dig up a sample of that and with the with the software that i’ll be showing i can interact with that and we can actually see some of that that communication right here on the screen so you get a chance to see that that modulation scheme and then how the software and the interconnections that we were talking about make that come about yeah on jt65 are going to touch on that good point jt65 just as a precursor is a new mode the one of the newer modes that is developed in recent years spearheaded by Joe Taylor and you all probably have heard of whisper wspr okay it’s kind of taken the hand community by storm and you got beacons all over the place a little bit of a is anathema to me a little bit having a unattended beacons all over the place but the comeback is that it’s low power and nobody hears it anyway so okay very hot Easterners ah okay the comment from the audience was that that whisper was very popular in the 500 kilohertz band and

I’ll repeat this from time to time so the tape kid gear the comments yeah no doubt and it’s good for propagation forecasting and so on but comes back to come back at the point jate what excites me is the actual communication that would come about from that so whisper is a method for beaconing and remote reception on a on a waterfall p SI waterfall display i’ll define some of these terms if there if it’s unfamiliar to you it fits one way type of communications but the techniques with the protocol are used to form a two-way conversation but it’s still really really slow communication if you know what I mean with slow speed it’s a communications thing and a mathematics kind of thing but with slow speed comes much lower bandwidth with lower bandwidth comes the ability to have whatever transmitted power that your true that you’re transmitting in up your into your aunt China concentrated into that lower bandwidth and on the other side on the reception side it makes it much easier for the received receiving station to receive that signal it’s you know it’s sort of like there ain’t no such thing as a free lunch tensa novel novel times okay takes a professor didn’t know that right yeah so you pay for it one way or the other but nonetheless it’s a it’s a I’m enjoying that aspect will touch on jt65 okay so here is digital communication just this is like a layperson zone not quite a layperson certainly not a high-end technical definition description of of modulation techniques and so on and I didn’t even bother putting up whether it’s a one type modulation or a 3j and that for the purposes of this right now we’ve got a standard we’ve got a standard call it a architecture this is what we see normally in in a this can be considered a very simple direct conversion transmitter and then turning around its kind of receiver you’ve got a local oscillator here this is the thing that you’re turning on the front dial that’s your local oscillator l/o and it produces a carrier frequency FC this is about as technical as ready yet so kind of bear with me and over here we’ve got the signal called FA I have no idea what a stands for audio good point and because then has this really is based band direct conversion so here we’ve got an audio oscillator of some sort so like sort of bastardize the the the architecture a little bit but saying for voice what you’ve got here is modulated voice a microphone that’s coming in here and the audio frequency is coming into this mixer and you know that when you mix a carrier with an audio frequency you’re going to get the sum and a difference coming out of the mixer the sum and difference frequencies a filter off one side or the other and for example and then you end up with SSB single sideband here’s the carrier frequency and generally we would get a mix of the audio with the upper sideband and what’s not shown here would be a corresponding frequency that would be on the lower side of that carrier but the Bay of the bandpass filter filters off this right here such that all we get all that gets transmitted out the antenna is the upper sideband so the energy of the voice is sitting right in here modulated on top of the carrier frequency so if you’ve gots like 77 point 0 40 megahertz 7 megahertz and you’re just talking and your boy your voice is what about 2.5 kilohertz a standard width of a psycho side band signal so this range right here is seven point 0 up to a 72.5 no 702 500 so that’s that’s the that they’re my only point in doing this is that the signal coming in gets modulated to produce that signal there that’s sideband when you’re talking when you’re doing the CW there are a couple of ways of producing it but one straightforward way is that the CW would key this little oscillator on and off that’s on-off keying to do to do do do do to do what

help that help that audio oscillator which is probably going to be set like to eight hundred Hertz or six hundred Hertz is a very typical offset CW offset if you remember any of the some of the menus in your ft 8 17 or your MP 1210 seeeeee and the signal is goood so it’s going to pop up and down again my point is that all it is in CW is generated a single frequency sort of up up there now to my point digital you know you might have thought that digital communications was really kind of esoteric and tremendously complex equipment in order to generate it but really not quite so there’s a little bit of call it mathematics magic in there but the bottom line is that your digital communication since that’s somebody sitting at a laptop and they’re entering data you’re typing text and the bottom line is that this computer is sending out ones and zeros streams streams of bits that are 1 or 0 that represent your ASCII text that is being transmitted these tone these ones and zeros essentially our input to it just like a tone generator in a certain way but that tone generator is what gets put into the balance mixer and again produces the same kind of this the same mechanism for producing the signal up here at seven dot 0 70 which happens to be a popular digital watering hole where many digna lapin on 40 meters digital signals so this the ones and zeros that are being typed here in the computer ultimately generate some tones which sometimes happens in the actual software on the computer there’s phase relationships and there’s mathematical equations that are performed in an ADEA in the DSP sound card in the PC but bottom line is that the pc is generating those ones and zeros which then form a couple of tones that are modulated or shifted by 90 degrees and form the mud the basis for the digital for the the standard kind of a 3j SSB signals that a standard transmitter standard SSB transmitter puts out and that’s where that same location is on the output maybe it’ll become a little bit clearer downstream and we can come back to it but there the point I wanted to make is it’s really not too much more than that oftentimes we leave the magic to the software program on the pc that does that and we don’t have to worry about that sometimes it goes in an external device it doesn’t even need a pc i’ll talk a little bit about this i mentioned i talked about this yesterday you might have seen it in our demo room but what will come to this but in here is that the software algorithm that actually performs that generates those audio tones but using the same mechanism to put up the spectrum on your antenna alright so I sat down late one evening and just started writing down the different modes that are around you might recognize some of them I didn’t and then I looked it up to be honest I looked it up too because I didn’t I knew there were more than I could remember and indeed there were there’s some lot of experimental ones’ all sorts of different modes each one curiously has its own little standard now that’s obviously if it’s encoded into a computer in some way it obviously needs to be that received signal needs to be decoded so the standard exists oftentimes again it is either by a special group military perhaps or designed for certain strengths again whether it’s low power or entirely accurate bless you or entirely conversational so each one has its

strengths some are older and some are you know I didn’t even put CW on there and I should have gone gone here I was David I were talking about it yesterday the the the digit is this is funny the digital world peep the people of digital world call ready the oldest whereas it is summers up there call that the oldest digital mode and it did it could be but again CW is digital I can’t get any more digital and on and off so but but it it would normally be grouped in here and here’s jt65 someplace did you see that there oh yeah there’s four six meters well 55 had this is like one of those word games you know with uh oh here’s the word here that can go this way and backwards backwards over there and a whisper whisper is there so what we’re going to do what I’d like to do is to take a handful of them it would take me like all day to go through and talk about each one but what I did is I selected a sample of them and again an audio sample with each and just to kind of put it in perspective when we’re done going through better or maybe six or seven of these modes and talking about its strength in popularity and whatnot we’ll get into what it’s going to take you to set up your station in order to do this and believe me it’s going to be straightforward in fact I don’t want to leave my hand too much but I think it’s pretty important that you know sometimes we heard over in the other room oh you got to make sure you got the biggest horsepower machine and the sound cards got to have like 500 bits and it’s got to be able to have a very fast you don’t have to have the latest humpty-hump system in order to do this I do it on a smaller laptop that I have at home I augment it with a wonderful little external USB sound card it was like 50 bucks from amazon.com and i’m able to do all of this stuff I within and it is very little problems in a setting up it’s a little a little bit on you start pushing the envelope a little bit when you want to start talking with two soft rocks for example when you get into these SDR software-defined radio which is a very close cousin to this whole digital mode set up but the basics of operation is pretty straightforward as we’ll see oh hang on your question a second you had one probably really too much looking at modes versus there’s a psk31 and psk63 and why is that well I’m wondering if you’re going to tie those them together I mean this it as well as we just 22 speed greater than 31 errors and more there’s close derivatives of each other and that’s about what they are often times it’s the bit the bit rate that is being talked about so 63 typically would be 63 care of 63 baud or bits per second psk31 is 31 bits per second so it’s a related to the bit bit rate and it’s something keep in mind is what I mentioned earlier is that independent on the on the application that you have if you’re if you’re transmitting information to military overseas you’ll want to make darn sure then the information gets there the transmission gets there and that it’s accurate so in that case you want to use something that is that is high power and probably as a result a pretty wide bandwidth q our peers on the other hand and that’s where the genesis of psk31 sort of came about Peter Martinez what his one in it is one and only goal to this day and it’s interesting people say why don’t you have your psk31 do this he’s the father of psk31 why don’t you have it do that and he says no no no we must keep it 31 bits or 31 broad because the bandwidth a narrow bandwidth was his absolute requirement the second requirement was conversational mode on the keyboard so he didn’t want to be burdened with error correction so each of the different derivatives that we see up there of a basic of a basic mode tend to differ a little bit in those regards some you know the basic mode might not have error correction i know the b-mode might indeed have erican Direction error

correction psk31 versus 6363 is a higher bit rate which means it’s a higher bandwidth which means you need more power in order to achieve the same distance and and communication is integrity understand yeah I just wanted two basic pieces of enough to bother then obviously 31 spectively at the 31.5 Diego Padres so two times a decision free that’s the closest coincidence yeah exactly no no you’re absolutely right I just I’m filling an extra around your question too just because it’s kind of interesting to me at any rate you had a question yeah you to get hurt oh sure we’ll talk about the question is what motivated me to go the external USB soundcard route and I mentioned that in greater depth but it a quick summary is that I had a cheaper computer that didn’t have stereo I do SDR software-defined radio a lot and you need stereo input for SDR there’s a high channel and a cue channel quadrature audio signals and they both have to be input at the same time many laptops do not have the stereo input capability further some of the laptops most of the laptops do not have enough the sound card is not good enough it’s good enough for our purposes of you know talking to mom and dad over the so the kids over the skype but it’s not good enough to have good audio quality you need more bits you need to have a faster ad converter but i’ll talk about that and i’ll give i have a good link for that too there was another question I think yeah they’re very costs involved in the image of these fools I are their varying costs Claudia is it more expensive the equipment and software and so to get into Elizabeth no neural inai there’s always going to be an exception but but generally the whole one of the beauties of this whole thing and I think I had a title at one point I’m not sure if it’s still in there but the question was does it cost more to get on the air with one digital mode as opposed to another and the beauty is that once you get your system set up to input the audio from your rig your processing it in software mostly well one hundred percent your processing it and software and if you have a different mode you use different software the same setup for the physical the physical link as we say the audio is coming into the into the computer in the same manner every single time so the answer is pretty assuredly is no which is good except for pack door like I said right but in the old days in the older days before computers were really prevalent and you know used here there were dedicated demodulation or what would the column ot to use so terminal units were dedicated Hardware boxes that that filtered at specific frequencies were mostly [ __ ] rtty maybe others as well because the soft core was not either as the computers were not as capable back then or they just weren’t down and close to the user as they are today with the PCs and and frankly they were more expensive so better solutions you know pull out your 73 magazine oh and qst from those those later years or earlier years and you would see many audio amplifier circuits active filters phase-locked loops that would capture the frequencies being transmitted or needed for transmission by a given mode together again the whole thing is to transmit ammo a transmitter frequency in a certain way what’swhat’s the frequencies for ready 170 it’s one there are two frequencies that 170 hurts a part of what are the frequencies 21 21 25 and then + 170 okay so those two frequencies would tend to be the what your audio filters your active audio amps audio amplifiers were attuned to such that when to signal when the tone was present the output would be a mark or a space which is what Dave and I were speaking about yesterday for the CW when a tone is coming in at eight hundred Hertz if that’s what the Gertz

old filter on the DSP I’m the and the PC program or da da da on this here where it was tuned to we get a indication of a mark or space but anyways today mostly it’s his son to PC any questions David popular visual load yes actually okay well you know it’s generally that the question was what is the most popular digital mode I think psk31 is the general acknowledged most popular one it’s huge it’s huge from an aged length riddhi has been around longer there’s probably many many old-timers that have been using that for years and continue to there’s a big by the way there’s a big ready contest you know what the the contest is coming up it’s in a weekend or two so after this when you all go home and you fly home and you and you order your your your sound blaster x i 5 i’ll have the link up your sound card and you get the software you get FL dizzy in here or digi pan for just psk31 but FL digi will do ready there’s a big contest and you will be amazed I mean you you I’m sure you’ve heard how the the contests go and digital mode then it’s like total utter chaos and you say I got to get off the air for the weekend because there’s no way then I’m going to try to I’m gonna let all these these digi nuts digital nuts go you know go back to sleep but get you a little station set up and just tune around on the Reedy contest coming up you will be amazed how you just kind of move over a little bit and boom you get to some guy calling CQ you do you know return to seek you with him and you get a serial number and move over you’ll spend all day doing it it’s a ball but the point is one of the points is again the beauty of digital mode is that you can get so many signals in a small bandwidth that it just means like shooting ducks in a pond your charger and it’s just a lot of fun is there commercial ready is there much commercial ready um I don’t I don’t listen I don’t know I don’t listen outside the hand bands too much does anybody know I really most teams or two other modes happened in the most corrupted move now or he has erected even as a changeover okay so the answer answer is not not much commercial ready anymore commercial has changed over to more modern modes and probably adaptations of the of that to suit their own purposes no more international telex in the commercial world I don’t think you need to worry about let me do this the other way I think you can be encrypted you can we cannot send obfuscated adore encrypted messages here in the ham bands but it’s outside that at so military and other commercial use that maybe they can modify the routines the algorithms to to suit their purpose is there something non ham into 30 meter band so you hear digital information to digital transmissions maybe some curbing could be but the psk31 is is the acknowledged that everybody says is the undisputed king came about again Peter martinez back in 1991 1999 was the the father of it and he really and actually before that I don’t know if that some of you guys might remember I don’t know there was a thing called bpsk by phase 15 there was a fellow in Canada and he made two little boards like this in his stacked them and it was a very beginning that’s when I started and got into digital because I built his boards and it was it was sort of like when I first got onto the end of the internet and there was this thing called chameleon and a way to access the internet and it was all very arcane and different now today of course that the standards have evolved and who can even remember Netscape and comedic chameleon and all that that was the same way back then with Bill somebody but he was so helpful

and getting people on but that I think was you know bpsk and psk are there both of the same family Peter Martinez really defined the the mode standard and again his driving factor was that it was conversational mode and didn’t have to go any faster than one could normally type and didn’t care about error correction who cares if you know your type instead of th e well it’s not even the right way to do it but I mean if you’re if you miss type of all of us miss type and you so what right oh and by the way this is kind of this is an interesting thing here on some of the scope on some of the your your your rigs and certainly the banda scopes the spectrum displays on the programs that will show you did you pay and FL digi each of these mode has a characteristic shape this one happens to be by modal in that in this way here and you can see that each of these well you can’t see a too well but when the phase changes the ultimate ultimately the the spectrum energy changes slightly too so that the separation between these is like on the order well I think each is this plus and minus 15 Hertz from the center point so it’s like a 31 ish hurts bandwidth is where the most of the energy is contained the side lobe information or spectrum there is characteristic of of how well or not how well you are modulating your transmitted signal we’ll talk a lot about that because there’s so much emphasis given oh and guidance to 22 people when they’re doing digital modes to don’t put the power up too much we’ll show some examples in fact this is a little bit the samples here in the I don’t know what these are taken from whether it’s FL digi or what but the spectrum display this is what you would see on the typical program that you would load on your counter and each one of these things each one of these tracks railroad tracks if you will is indeed a transmission so there’s active signals going on there let’s let’s click on a sample we’ll have some other examples that are a little bit more characteristic of what the digit did the audio pick that up at all okay good so it was a little bit more characteristic it sounds like this funny if you have ever done a CW contest you know if you ever done to like go for a whole day or heaven forbid the entire weekend or liable for 24 hours you’re taking a shower or the next morning and you can swear that there’s CW coming from that faucet in the shower right your ears get so kind of in tune with this it sounds like crickets at least to me I’ve got crickets in my backyard a little bit of like a wetland behind me so in springtime there’s little peepers and in the late fall they turn into the building boom but in a springtime course like there’s a million it swears like that I hear a million PS carers back there in my in my backyard but do you get you get used to hearing this an awful lot and you can really hear what’s going on but anyways that’s uh that’s it and then if you very curiously you could actually use the sound card quality is not that great but if you have a nice strong signal you could use the you know the microphone that’s built into many laptops so you can do skype and talk to you know the kids and whatnot you could hold a recording of that and actually see the transmission come up on the screen will will show that as as we proceed through here I’m sorry I have to have to do I is there fire well I mean I was so convinced one time I took my laptop back in the in the woods just to see you know because you know who maybe there was some relationship this didn’t work you thought i was kidding about the Frog didn’t you okay so here’s ready it’s the oldest one around and I think it depends

on when where I got this information it might still be the most popular con testing one and believe me again if you just check you know check around to find out when this does riddhi weekend is coming up you’ll you really know what I mean the frequencies are tend to be standard here so the watering holes as I said our kind of common so if you want to hear a certain frequency I’ve listed those that are common to given band so go to there and just kind of hang out at 7070 for example 70 Sepultura I marked it on the on the psk 707 there you go so you get to know the frequencies that a given mode is on and they can then go and check it out it’s a good indicator to of course if there’s that the band is open so if you have the typical dependent on your your attitude of a digi trash come in and you can you can tell how how good the band is working that day it used the this is the sky have I have actually two I have two of these in my basement to these guys here and yeah they do it’s awesome I told him in a boat anchor so I mean anything that is old and I can get working I I just enjoy the heck out of it but I got then you hear that it’s a my mind as a model 19 to model 19’s and the smell of the oil and oh it’s awesome so you never want to see it again I know I know I can hear ya but anyway that’s what the old time and that was totally mechanical there was no electronics in there and then it needed that it needed that terminal unit that audio filtering technique in order to then add the audio the audio tones turn to mark in space at very specific frequencies specifically 45 baud 45 bits per second would be sent to that turn to send to the hardware and it would print out actual print out and whatever you type on that on that riddhi equipment it would generate the marks the just contact closures marks in spaces at that particular rate which would then go into that that audio that electronics box and generate the tones you know 21 25 and whatever the other one the linker subs whatever I don’t know what that is linker subsets a link hurt I don’t know that is sealed water actually make the clothes oh ok I use a tu I built a ripped off I ripped I built a copy of st five it’s a common one I thought yeah maybe age of iron game yeah yeah yeah and even more things for that here’s the I need to move along a little more quickly sorry you can actually an actually hear the two tones a lot better there be the separation is tremendously more 170 hurt separation versus the 115 hurts our yeah the 15 hertz plus minus that psk31 offers so that’s why the closer they are it sounds more like a cricket as opposed to two tones that are going back and forth again very common sound on the on the air all right now packed or somebody knows pack door I don’t use I’d know too well but this is also it’s kind of an older one it’s error free which is one of the one of its characteristics so it’s got error correction a wider bandwidth as it says they’re probably two times the bandwidth of what’s the Frog where’s my frog so you hear that that pulsing that burst and a lot of it is used for mailbox’s you probably have heard of I think I’ll talk about packet here also so packet was used for sending emails / hf and vh up as well and this is a mode that used to send information posted into bulletin board or BBS’s and as it says here because of that error

correction under one of the trade-offs to get error correction it takes a long time to send a message and especially if afef if the path is imperfect or a noisy qrm type of Bay q RM or QR and why because if there is an error detected in the transmission that transmits it again so it’s whether that hand that it’s it’s it takes longer to recover on a full accurate signal yeah is there any software or only way a new backboard and at Harvard one no I think I think we there is there was hardware solutions back earlier right so in other words the question was is there hardware required or neither now or later or earlier was the hardware required for pecked or probably of course all right first and give them and you can only buy them at CS CS okay so pecked or three is the one that has proprietary in implementation and hence would need a hardware solution and it happens to be proprietary from SCS yeah the Vinland in two thousand folks and comfortable anymore go forth and a founded group presentation BTW last year and they’re getting comfortable that reserve replacement pack worth three and the first very look a healthy by side so win more again i’ll repeat these things for the audio but when more is a solution for packed or three did you say yeah but again so it’s you’re paying for the the perfect copy is this bottom line if you want to do that implementation okay if I understand check out this tone I really like this it makes sense how many tones do you hear they’re cheap now Dave and I can probably relate to this how many gürtel filters are do we have run it at the same time as a result probably any kind of a of a computer program that is filtering on these tones and again it all comes back on the receive side I’m the transmit side it’s simple and whatever the algorithm is to generate a tone your computer program is generating the tone at this if you’re if we’re talking spectrum wise here’s a town here’s a tone here’s a tone come each of these is a different frequency so whether it’s a 16 or 32 or eight there would be that many different signals kind of occurring at different times so it’s kind of like there’s a lot of combinations if you work up the mathematics of that a lot of bit combinations and again I’m not sure if this one has error correction or not but it’s really good for poor signal conditions if you’re at all into spread spectrum communications one of the benefits there one of the benefits is that if the if the signal that you’re working on if this frequency that you’re working on is kind of has noise or interference or jamming there are it’s this broad spectrum there’s a semi-random generation of what frequency you would go to beyond that but you’re always hopping around in that area this is a similar way in that it’s transmitted on multiple frequencies so the band the algorithm is able to actually use that multiple or sometimes redundancy in order to recover and perform well in low signal conditions low signal conditions is when your signal is low to the noise floor there might be a lot of noise that’s messing up a certain tone but other tones are getting through and as I says tuning is really critical for that is if if you’re transmitting on these frequencies you want to and you your receiver and your receiver is it got to be kind of lined up on all of the frequencies and they have to be well calibrated to each other too and not have different spreads if you will power

levels yes yeah generally technically it’s going to take more power and presence in business that’s the key and that’s the key so the question was you know what’s the relationship of the power versus the bandwidth is really what it comes down to if you have a higher a wider bandwidth such as we have here the the same if you have the same amount of power going into generating signals in a wider bandwidth generally it’s not going to go as far if you want the same kind of copy at the end between the two stations transmitting and receiving you would have to put more power into a scheme that has a wider bandwidth now there are techniques to kind of counter that there’s all sorts of techniques for example each of those different frequencies are very specifically set here the the either the eight or sixteen so you could envision having little signal generators and very narrow signal detectors on the receive side at each of those so cumulatively they might be operating over a widespread but each one is a narrow bandwidth to its own tone today because we because we need more bandwidth but you have more men similar is Emma sk16 have a better transmission rate for a given distance I see what you mean and I don’t know I I honestly don’t know I’d have to look it up in myself so the question was you know does forgiven power level does mfa MF sk eight verses 16 which is the better for a given distance and power level I’m not sure so I think you know there are studies in comparisons that you could probably easily check that out and it kind of brings me to the point I want to let me go all the way to the end if I can but right here is some useful references I mean there could this could be pages and pages and you can find something similar in you know just do a Google search on digital modem ham just to kind of narrow the field or digital digital modes ham would really resolve that for you but right right here this website if you search on g4 you see jay i unabashedly grabbed a lot of information from his website and he has more information that I could even possibly fit in here and sound samples included and hence I credit him though but my point is is that this is a great website that can yield you some really good information so check that out for sure my address is at the end but the simple one if you just want to contact me as n to a PB @ verizon.net so if you got a question that comes up along the way you feel like you I might be able to help you in some regard feel free to write me no problem at all and to a PB @ verizon.net hell Schreiber is loading so here’s the one that they call is the oldest one okay so my apologies on that it’s not ready but it’s a it’s hell schreiber a really interesting thing about this one is that it’s actually transmitting a bitmap what I call the bitmap but it’s a picture so they’re just taking I don’t know how they generate it to tell you the truth but they generate the signal as a that it’s called a ticker-tape display now this is the ticker tape I think that’s this here’s here’s a ticker tape right here so this would be the first line if we be displayed you go up and then the next one to come down here and you see some obvious overlap so it’s almost like the source material that was scanned in lines width of that much right and there’s no attempt to make it error correcting correlate a character and rip reproduce a character on a screen that was ultimately sent from a transmitter just transmit the image and I’ll let your brain your eyes do the correlation now anybody can it fairly easily see this is call you’re probably

thanks for the call your rst 579 579 QSB name blub blub and and so on so your i can extract i can extrapolate and interpolate and extrapolate the information now imagine it holds down da haterz britain want to da you all do that as they were even though today’s modern printers i mean you lose a an ink cartridge and just sort of like you know I’m missing the blue ink but i can figure out what that is dots yeah same thing yeah now you’ll get a kick out of the sound maybe not so it’s like grading it’s a grating as I said up there like a white um yeah well it kind of makes sense the comment was a sort of sounds like a fax machine the older when you actually hearing those tones economically okay baby hanford well let’s so I don’t know the bandwidth for this it’s hard we don’t know the resolution on this scope signal on this spectrum signal so ponsor what is it is anyone home and will do very fantastic year that we are I general with it’s obviously I there’s a grayscale there’s a grayscale in and Thresh holding so I don’t know yeah every character that my nature so I eat that part of me did well not so not so it’s not a character with a with a matrix dimensions because this this is this is the resolution I mean this might even be one this is this this right here what I’m outlining is probably the width and of the the resolution of that particular scan and it could be a picture of your frog and then and it would transmit across this just happens to be a picture of some text I don’t done I’m just not familiar with it enough to know you know the mechanics of how the scan was generated but would they say go to hell this is what they’re really talking about I don’t say it here do I I used to have it but I think I cleaned up what to have and prime county is over the wire 62 hurts ok very very oh yeah that’s amazing 62 and a half is not bad that’s like psk63 well 63 and a half 62 now oh I know it’s a pre-press industry I come from that long time ago says I don’t you think it is the question is where did the name what was the derivation of the name given that we know that there’s a german company named hell that it was a it was a company that does drum scanning real high resolution image scanning you wrap the image around a drum and there’s a line scan that this process presets too long or processed along the the drum may be so does anybody understand German Schreiber’s and actually i think the hell is not a scanner it’s a writer it’s a it’s an image writer that the hell product from Germany so that could well be I’ll be darned yeah yes okay we’ll do a couple more of these then we’ll jump down to some we’ll skip the rest you’ll be able to see it in the slides and the samples and so on let me just see let me in fact let me just let me just do this okay because I think it’s kind of cool let’s listen to

the packet now as it says here there’s a dressing on these packets which are typically used for a bulletin board and email and types of postings here is the address of where that information is destined sort of like a like an IP address of the earlier days and this is the information content you can really become the hit of the house if you turn if you turn this on in your rig and you let it go all day long on this is cool olivia is cool it’s pretty new it’s very it’s a wipe it’s a pretty wide bandwidth and it uses a lot of the the tones I was talking with the multiple tones you heard that before I think it’s now i’m not i’m not gonna profess to be an expert on all of these and many of them but the bottom line is that there are multiple tones that are used in the out and the algorithm for generating representing the information that’s being transmitted and hence a synchronizing on the receive side to to get those tones and whether it’s a time-based a time-based would you call it dave a time modulation time-based like CW on or off at the given frequency or whether within each of those different frequency whether there is further modulation and phase shifting and so on I don’t know I just don’t know but the point is is that you can there are very clever ways that people you know much smarter than than me have been able to be generating and recovering information and that’s why we have such a proliferation of these automatic link establishment is kind of an interesting one it’s used so it’s used for obviously in fact you might have heard a little bit about this or imply to look get what Bob Byrne inga was working with the starts getting into you know using transmitted information and for some reason I couldn’t find the spectrum display on this one but used for connecting two stations alright jt65 is the one I wanted to touch on there’s a lot of good information on this and of course Joe Taylor is just absolutely an amazing guide and and again the bottom line is that it’s a derivative of his basic alder algorithm and started with the whisper and wspr weak signal propagation anyone who was is that right yes okay good I was hoping somebody with no more jt65 ziebell were moved out oh goodness most everybody knows you want to arise for listening hours merci beau and he went better way of doing transmission off moon was uploaded I’m all we did CW you listen for the CW Sam inside the weeds and joe came up with jt65 and do a lot of people that your keys are so are you and see no he’s the other way Americans are always a jt65 sprayed myself I work off the moon on two meters didn’t supply be about 80 countries confirmed all right Joe just received his dxcc 574 2 meters all right just no where the number into art is thoroughly one so it’s 17 think somebody else’s wife there’s that’s amazing and 65 is what some of the door for all of us to bracket the bracket up I’ve been going for about 13 years okay how long does it first of all cliff are you getting any of that audio good okay thank you very much for the offering that how long does it take to do in a typical confirmation q so just a quick you know 559 or two to two in what I had transmissions i’m sorry mr. everything is being a weapon transmission right alright see you receive per minute transcript for men you’re either on the

odd time or the even tops i got a minute the transmitted you got one minute transmit they listen for one minute jordan out one minute and you’re actually running from the beginning of your time for about 50 seconds at 50 seconds it cuts off from 50 seconds until the one minute I’m it decodes the information that is just picked up that information once I picked up is then written out and screen so most guys would send their your call either the original part would be your call my call your phone my foyer oh my co your quote for 50 seconds then if you hear it he say yeah I got it I got his call his grid that I’ll turn around i’ll send o’s so i said his phone Michael Oh Michael okay okay I got it and it’s all done one in one minute see one it sounds interesting it sounds like a long long effort but it’s for the effort you know you’re it’s a low it’s how you really able to dig the signals out of the ground you’re being stationed out ok actually here it is neither other times you never hear you just see it for it out there you go so there’s a lot of information on this and obviously being them probably one of the more popular new ones that we have some specially sort of specialists some guys are starting to concentrate a lot in that and a lot of information on the internet so you can check that out for sure I’m sure just check out search on jt65 and and and whisper in general we have somebody just FYI we have somebody that’s working on putting whisper beacon capability into the SDR cube into the SD r cubed transmitter my transceiver so I’m hoping that I can take that and extend it to to be jt65 actual transmission capabilities obviously frequency state synchronization and stable at time synchronization is important as you were saying we will have we all use a higher at the end we’re all kind in there you have to listen very carefully here this is i think is this characteristic of what you would be hearing or do you not even here we give water media support and be receiving about 90 years okay let me move along we’re going to be coming up we have 15 minutes left okay so there’s there’s a smattering oh how about that there’s a smattering overview let’s get into actually how you would construct a very simple straightforward hf digital station as I sort of indicate they’re here all you really need is a laptop of some sort I mean maybe better than a nineteen ninety vintage laptop would would be good here’s a picture of that sound card the the details will be shortly but it’s a sound blaster x I something and an SSB transceiver why can’t you use a CW transmitter a transceiver you know a lot of qrp rigs our CW only and you just can’t you can’t use that it’s not a linear and it’s not able to transmit varying levels of voice energy and so on so it’s got to be an SSP transceiver for most people most of us here obviously any of the commercial gear that you have is going to be SSB and the comment right here is we mentioned this before once you have this setup that’s it that’s all you need for nearly everything that we’re talking about okay the computer their recommendations and it turns out that XP or greater is going to be most helpful I’ve had just a lot of luck in general thankfully with windows seven so if you haven’t upgraded from windows 7 i’ve been to hold off on XP for ages and i just had to get a new computer and i couldn’t i didn’t want to uninstall windows 7 I gave it a try and I’m really liking it and so there’s growing support for it and it’s much more stable security as I’m a security guy cyber security guys so the security is infinitely better than XP Vista you can throw away

as most people indeed have you can use max just using them one of the more modern max they have better drivers and response times in the low level hardware the bigger they as with things in general in life the bigger the better this recommendation says don’t rely in the built-in sound card then hurt to try it you know what the heck just keep in mind that the built-in sound card is mono now let a mono monophonic as opposed to stereo Manos will work on everything that we’ve talked about here just fine so that’s not a big problem but when you get when we get to the sound card right here I’m going to indeed and there’s the address it’s is hard to search this go to amazon and search on creative blaster look for the X Phi X Phi surround go for stereo definitely go for stereo why because chances are some day some time once you get to hang of the digital modes you’re going to 12 gives SDR a try this isn’t an SDR talk but I got to plug it anyways if you really want to give a get into SDR and you haven’t heard about the soft rocks yet for like fifty five dollars you can get a kit it’s called the soft rock ensemble is the latest current one if you’re lucky to get it on their website fast enough but get the ensemble and it’s a three band transceiver that all it is what we call the RF front-end so you connected have to build it empowered with 12 volts you supply an antenna to it and most of them these days are going to have a USB cable so you don’t even need necessarily one of these you can go into the USB port on your computer and but I won’t even get into the hassles that you have with you get in the right USB drivers and the right versions and it’s it’s it’s it’s ugly yeah yeah uh not so not solid huh yeah you got to have a cable it goes over the Sun you’re using the sound card got into some card in the laptop we’ll talk offline at least the one I’m referring to it definitely does not have a codec it does not have a codec on it yeah we’re oh okay yeah we’re talking pretty much the same yes yes okay I’m just say what you’re saying the question that we’re debating you need soft rock the specific version of the software that we’re talking about the and sambal needed to use the USB only for power actually and controlling the frequency so control the elbow river that hello that I was talking about and then the two audio channels the I the cue coming out would go into either the laptop or into another device that reserved into some card thank you so again this is the heart of it this is like 55 bucks from amazon com and i use it for also i’ve got an old turntable i’m in the old-time bluegrass and i like to record el vinyl transfer vinyl to audio and i use this for that so I mean it’s like nine it’s 9604 another 96 kilohertz so it’s good enough for me I can’t hear it well to begin with so it it certainly works now there are other devices on the market that are pretty nice and these indeed have some of the sound cards built into them so this these are kind of cool and they’re nice because they also interface that they they isolate the radio your RF radio from the computer if any of you were over at my booth over there when the SD r cube is connected to our modem there would be a lot of digital hash that was heard sometimes you get hum and sometimes you get different voltage potentials between the two devices especially if they’re powered from two separate sources so it’s nice to ice up to isolate it’s nice to electrically isolate the the audio path and keep them nice and separate so what we’ve got is my friend it’ll it’ll take up RF energy it will dry the mouse

around oh yeah various conservatism RF chokes can be your friend those interfaces can be used instead of the sound part in some cases yet on other cases I’m not sure exactly which items are shown there some of them just provide an isolation for the PTT so they go here’s a representation of a sound card it is relatively straightforward as far as taking your receive audio in to the sound card itself and having a sound card interface that that provides and that isolation we’re talking about and also isolation for the Keen or the PTT or it turns out you can make it yourself I mean I see it so it’s pretty easy to make these this is not up to i saluted at all but nonetheless it interfaces pretty easily on most rigs software there’s a lot of different software programs out there that can actually decode and generate FL digi is by far the most popular this is a pretty busy screen bottom line is that if we have time afterwards maybe often enough in the lobby we can actually show some signals coming in and being decoded the the tones coming into the queue so if you will of course the text is right here and all sorts of logging and different kinds of time stamping there’s a lot of capabilities along along this particular the menu bar so it just dies free search out of FL digi you’ll download it from a certain any number of servers another one that I just love I first of all I love skip teller k h-60 why he and his buddy Nick generated digipen a while ago and I it’s you know psk31 is the most popular most prolific and NL of this program i use this for testing all of the new psk modems I just it’s just a very intuitive type of program it’s free download it’s always updated to the latest and again you see a nice as with FL digi you see a lice a nice waterfall display of the different signals we didn’t talk much about it but the bottom line is that you have to make sure you don’t overdrive the transmitter because when you do that you get a lot of splash and splatter and one large one very overpowered signal might produce all sorts of side bands down up and down a band and you become very unpopular very quickly on the bands and sort of wrapping it up here you don’t need a pc again is is my buddy Alfonso bedoya in 1948 said you know badges badges we don’t need no stinking badges all of this stuff with the pc is very cool there’s a lot of power in the pc there’s no doubt about it but i don’t like taking my pc to the field overnight in the damn tent up on top of a mountain top maybe dropping it hard to see in the sunlight i’m not going to take this this mama that i’ve got here there’s no way I’m going to think that anywhere in an uncontrolled way so the processor the embedded processor in here admittedly doesn’t have all the bells and whistles of FL digi there’s a lot of power in those or SDR polar SDR when it comes to doing SDR stuff but there’s nothing better than taking this plus your ft 8 17 your SD r cube and you got it you can do digital modes and we’re always adding new capabilities to the software you can easily update it you get this thing once you just continue downloading the new modes the new software algorithms that we provide on the website and you know it’s pretty straightforward and simple I like simple and that’s I don’t have to deal with the drivers and the version number of the operating system and the reboots and in dings and Boop’s coming in get transmitted over the air because my mail you have mail you know that kind of stuff there’s be careful about audio levels i mentioned don’t overdrive there’s a technique that says use your alc to make sure that you don’t overdrive and serve as an example of some of the splatter can be pretty bad alright so what’s stopping you get your get your sound card get your laptop I know your wife and kids with all that noise start hearing crickets in the backyard look for that frog in your pocket and have yourself a good time all right any uh can I can answer any questions in the moments that we have remaining hope you I hope you enjoyed the presentation again my address email address is n2 a PB @ verizon.net I’m I’m

always on and I’d be happy to answer any questions if you have them and give you a hand or a pointer on is this sound card good or what’s wrong with that program or what’s an advantage of Mt 63 I’ll find out the answer for you if I wasn’t able to do it here today okay thanks a lot guys