[digitalradio] Introducing the KJ6VW Half-square antenna
See http://www.obriensweb.com/halfsquare.html for a brief article on this antenna that I have found easy to build and has improved my signals Andy K3UK
[digitalradio] Characters per minute and Words per Minute - convert ?-
Q How do you convert between Characters per minute and Words per Minute .. is CMSK-8 data rate faster than MF-1 ? CMSK8 7.8125 12.5Hz 3.75 WPM 12H5F1B ROSMF1: 16.7 characters/minute Tnx -G.
Re: [digitalradio] Introducing the KJ6VW Half-square antenna
Andy, The "half square" is of a family of "self contained verticals" that Cebik (www.cebik.com) described as such, and includes the bobtail curtain (like two half-squares together). It does not need a radial system - that is what the "self-contained" means - the ground system is contained in the antenna (i.e. the horizontal phasing wire). A bobtail curtain, or a half square, can be made out of almost any wire and just hung between two trees, with the coax at right angles to the vertical wires. The bottom of the vertical wires should be about 12" or more from the ground and protected from being touched by either being higher than a person or insulated. I used pvc pipes to protect the ends from being touched. If there is room, the bobtail curtain provides about 2 dB more gain than the half square. Both antennas are essentially verticals in phase, with the accompanying gain increase and no need for any other ground system. You can even create a beam out of two SCV antennas, but it is no longer bi-directional. A bobtail curtain beam is the antenna I used in Hawaii and covered all of North America and Canada without any need for a rotator, but I was 5000 miles away, so the pattern was very wide at that distance. 73, Skip KH6TY Andy obrien wrote: See http://www.obriensweb.com/halfsquare.html for a brief article on this antenna that I have found easy to build and has improved my signals Andy K3UK
RE: [digitalradio] tuning of SDR radio
Yes, a very interesting idea, but would this then be the mouse? Or can you run two mice at the same time, one to be the mouse and the other to control the SDR? One thing for sure it would be a lot cheaper than buying a Griffin. Would like more information from the project group if possible. I am sure there would others interested as SDR's become more main stream. Regards Kevin. From: digitalradio@yahoogroups.com [mailto:digitalra...@yahoogroups.com] On Behalf Of Vojtech Bubnik Sent: Wednesday, August 18, 2010 4:54 AM To: digitalradio@yahoogroups.com; "qrp-l" Subject: [digitalradio] tuning of SDR radio Hi gang. I found a great idea for tuning of SDR radio using a cheap mouse and rotary encoder on www.cq.sk http://www.cq.sk/img/sdr_rotacny_enkoder.jpg Just buy a cheap mouse (Genius NetScroll 1200 on picture) and replace the whell optical encoder with a panel mount rotary encoder with knob. It is certainly a cheaper solution than to buy a dedicated knob product. 73, Vojtech OK1IAK, AB2ZA <><>
[digitalradio] Re: New guy
Some of your questions are sort of "which taste better -- apples or oranges?" and you may get all sorts of different answers depending on personal preference. I'll give you some of what I believe are the differentiating factors. I'll also tell you my personal decisions but they are mine and others will not agree because it's a personal thing. HRD vs. Others: There are a couple of programs like HRD, FLDIGI, and MixW (plus a few others whose names escape me at the moment) that are multimode and can do pretty much any of the "soundcard modes" (i.e., those digital modes that can be done with soundcards and don't require special modems, special TNCs, etc.). Then there are those built for individual "soundcard modes" such as Digipan for PSK and MMTTY for RTTY. In my opinion (and it's only my opinion), the primary difference is that if you go with a multimode program, there is a higher learning curve up front to get started on your first mode but then almost no learning curve to go to the next mode and the next mode and ... If you go with a specific program, you have a moderate learning curve up front for your first mode and then a similar learning for the next mode and ... Essentially, if you're going to do multiple modes it comes down to "pay me now or pay me later". Of course, you'll have the learning curve of best operating practices for each mode, but that has nothing to do with which software you're using. When it comes to capabilities to work in a given mode, I believe that the major multimode programs are as good as the equivalent single mode programs. For example, I believe that HRD or FLDIGI are just as good in PSK as is Digipan or any of the other PSK programs. Personally, I decided to go for a multimode program. I like the fact that I only had to learn the user interface once and could then quickly pick up additional modes. I regularly switch back and forth between PSK, RTTY, Domino, MFSK, MT-63, Olivia, etc. depending on what I'm hearing on the air, and being able to do it by clicking a button rather than shutting down software and opening up software is a major benefit in my mind (others may disagree, especially if they prefer to work one mode only). I would also say that if you have the smarts to get your general or extra ticket, the learning curve on HRD (or on FLDIGI) is not going to be a hindrance to you. As to outboard vs. inboard soundcard -- again a matter of preference. When you go "inboard" soundcard, you're depending on the soundcard that comes with the computer and you're depending on the computer having enough speed and memory to run the soundcard and the software at the same time. Not all computers do -- especially some of the cheaper or older computers. When you buy an "outboard" like the SignaLink, you know you're getting a soundcard that works well for this purpose and does not take much memory or processor speed. I prefer the "outboard". My primary ham radio computer is an Acer netbook and the internal soundcard is not as good as the soundcard in my "outboard" (a SignaLink USB), which means that I do better with the SignaLink on that computer. I do a lot of EMCOMM work and I like the fact that I can move the SignaLink from computer to computer without having to worry about whether or not the computer's soundcard is adequate. Cables -- believe it or not, another preference thing. If you buy one of the major soundcard interfaces such as a SignaLink or RIGblaster, they come with the cables you will need (you will specify which rig you have and they will include the right cables). There are people who prefer to build their own cables and even build their own interfaces. Depends on whether or not you like to tinker with a soldering iron. Knowing how many things I've ruined with soldering irons -- having built an Elecraft K1 AND two Elecraft K2s -- I didn't want to do any more soldering for a while. Note that the cables that come with the soundcard interfaces are for the digital mode, they are not the cables for rig control (actually changing frequency, power, and other settings through the computer). The 756 has good capabilities for that if you want to use them (you don't have to -- you can control the rig manually, which is what I like to do). If you decide to do computer rig control, you will need an additional cable and you will certainly need software that can do the controlling. Your 756 user manual specifies the cable needed for that (or you can build your own). Both HRD and FLDIGI do rig control as well as digital modes, and that might be an argument for one of them if you decide you want computer rig control. Wow, I've written a book. Sorry about that. I hope this helps and I hope I haven't started a flame war by expressing my preferences. Jon KB1QBZ --- In digitalradio@yahoogroups.com, "Stephen" wrote: > > Is HRD the program to use, or should I start out with somethig that is
[digitalradio] off line for a while
I'll be off line for a while - having a big problem getting my email program to work with Hughes net. And I almost have to fix it myself since I CAN"T understand what the tech support guy in New Delhi India is telling my. No speak that broken whatever it is. John, W0JAB
[digitalradio] Unknown Digital signal????
Hi ,,, got a question for you guy's... On 3.860.00usb to 3.863.00usb there is a digital signal. Does anyone know what type or mode the signal is and possibly where it's coming from. Comes on about 2400 Zulu and is annoying as hell Hoping someone might know... Thanks.. kc2axu
[digitalradio] Re: Unknown Digital signal????
"If you hear a rough-sounding and very broad signal centered at 3860 kHz there is a high probability that the source is a T1 data line within a half-mile or so. Internet data service provided by DSL, wireless, and various other means sometimes is referred to as T1 where the bandwidth approximates T1 bandwidth. However, they are not true T1 circuits and do not cause 3860 kHz interference. True T1 lines carry what is called a DS-1 signal. The data rate is 1544 kHz +/- 75 Hz. However, the transmission mode is bipolar using a code called Alternate Mark Inversion (AMI) which causes the pulse repetition rate to be 2.5 times the data rate. (2.5 x 1544 kHz = 3860 kHz) Signals at that frequency are sent in both directions down two 100-ohm twisted-pair balanced transmission lines that are often not shielded. Changing to shielded lines significantly reduces interference radiation." --- In digitalradio@yahoogroups.com, "kc2axu" wrote: > > Hi ,,, got a question for you guy's... On 3.860.00usb to 3.863.00usb there > is a digital signal. Does anyone know what type or mode the signal is and > possibly where it's coming from. Comes on about 2400 Zulu and is annoying as > hell Hoping someone might know... Thanks.. kc2axu >
Re: [digitalradio] Unknown Digital signal????
There are some known European users in that range, but without a recording, it would difficult to say for certain what it is and where is it coming from. However, keep in mind that while this frequency range is assigned to amateur radio exclusively in Region 2, that is not the case in Europe and Asia, and so you have military, governmental and other users that are authorized to use the band. Dave K3DCW On Aug 21, 2010, at 11:35 AM, kc2axu wrote: > Hi ,,, got a question for you guy's... On 3.860.00usb to 3.863.00usb there is > a digital signal. Does anyone know what type or mode the signal is and > possibly where it's coming from. Comes on about 2400 Zulu and is annoying as > hell Hoping someone might know... Thanks.. kc2axu > . > > > Dave K3DCW www.k3dcw.net
Re: [digitalradio] Re:Streetlight RFI found with AM portable
Paul, That's a nice rig to have. I understand it's capable of AM mode as well - add a small hand held 2 meter Yagi and you'll have one FB direction finding RFI detector. Tony -K2MO I live near the Atlantic Ocean in "Slower Lower" Delaware. Our problem here is that during dry weather, we get salt spray on the power lines and transformers, leading to all sorts of noise. A good rain helps. I have a small Yaesu VR-500 wide band receiver. It works very well for tracking down RFI/EMI around the house as well. Good way to find offending "wall warts," and the like /paul W3FIs __ Information from ESET NOD32 Antivirus, version of virus signature database 5384 (20100821) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com
[digitalradio] Re: New guy
Jon, Excellent explanation! You should be a teacher (if you aren't already). And, Stephen... welcome to the hobby and digital modes. Here's my personal preference with some elaboration: Interface: USB Signalink USB Signalink has an on board sound card so you don't have to tie up your computer soundcard. It also only has 2 cables... one to the radio and a USB to the computer. Power is supplied by the USB cable. I've found the devices with rats nests of audio and power cables hanging off them give a much greater chance for picking up RF and locking up your computer. Software: NBEMS / FLDIGI (www.w1hkj.com) FLDIGI multimode software is built for all major platforms. So, if you go from Windows to MAC, you just download the MAC version and away you go. This is a preference thing, but I like the single window display of FLDIGI. However, if you're going to get into contesting, I think the logging and automatic rig control may be a bit more advanced and better refined on HRD. Rig control is where your radio and software share info such as frequency, filter settings, volume, etc. You can change frequencies and settings on the rig from the software. I've not had much luck with NBEMS rig control but I don't care enough about the feature to bother to trouble shoot it. With regard to the software the good thing is both HRD and NBEMS/FLDIGI are free, so you can check them out and see what you think before going down one path or another. I'd take up some of the fellows offers to help you down your way. And if you can meet up and have someone give you a demo, that's the way to go. The first time you open some of these programs, it can look much more complicated than it actually is. Good luck and let us know when you're ready to make some digital contacts. I've chatted with quite a few hams in LA on both digital and phone... maybe we'll get lucky and meet up on a good path. -Dave, KB3FXI --- In digitalradio@yahoogroups.com, "JonP" wrote: > > Some of your questions are sort of "which taste better -- apples or oranges?" > and you may get all sorts of different answers depending on personal > preference. I'll give you some of what I believe are the differentiating > factors. I'll also tell you my personal decisions but they are mine and > others will not agree because it's a personal thing. > > HRD vs. Others: There are a couple of programs like HRD, FLDIGI, and MixW > (plus a few others whose names escape me at the moment) that are multimode > and can do pretty much any of the "soundcard modes" (i.e., those digital > modes that can be done with soundcards and don't require special modems, > special TNCs, etc.). Then there are those built for individual "soundcard > modes" such as Digipan for PSK and MMTTY for RTTY. > > In my opinion (and it's only my opinion), the primary difference is that if > you go with a multimode program, there is a higher learning curve up front to > get started on your first mode but then almost no learning curve to go to the > next mode and the next mode and ... If you go with a specific program, you > have a moderate learning curve up front for your first mode and then a > similar learning for the next mode and ... Essentially, if you're going to do > multiple modes it comes down to "pay me now or pay me later". > > Of course, you'll have the learning curve of best operating practices for > each mode, but that has nothing to do with which software you're using. > > When it comes to capabilities to work in a given mode, I believe that the > major multimode programs are as good as the equivalent single mode programs. > For example, I believe that HRD or FLDIGI are just as good in PSK as is > Digipan or any of the other PSK programs. > > Personally, I decided to go for a multimode program. I like the fact that I > only had to learn the user interface once and could then quickly pick up > additional modes. I regularly switch back and forth between PSK, RTTY, > Domino, MFSK, MT-63, Olivia, etc. depending on what I'm hearing on the air, > and being able to do it by clicking a button rather than shutting down > software and opening up software is a major benefit in my mind (others may > disagree, especially if they prefer to work one mode only). I would also say > that if you have the smarts to get your general or extra ticket, the learning > curve on HRD (or on FLDIGI) is not going to be a hindrance to you. > > As to outboard vs. inboard soundcard -- again a matter of preference. When > you go "inboard" soundcard, you're depending on the soundcard that comes with > the computer and you're depending on the computer having enough speed and > memory to run the soundcard and the software at the same time. Not all > computers do -- especially some of the cheaper or older computers. When you > buy an "outboard" like the SignaLink, you know you're getting a soundcard > that works well for this purpose and does not take muc
[digitalradio] Re introducing the KJ6VW...........
Hello Andy, It was interesting reading the description of the half square antenna you made, particularly the comments on the comparison between vertical and the half square. Being unable to hear European stations may partly explain why, when conditions do improve a little, I always keep seeing the same PSK stations from the US, and the ones which can see me on their screens are most often very weak to my QTH Considering the huge number of PSK users in the US I've often wondered if my R5 is "deaf", or lots of US operators are using wet string ! Regards, Mel G0GQK
Re: [digitalradio] Re introducing the KJ6VW...........
Mel, we might start with an assumption that my vertical could be designed better . I just took it down and plan on making a better on Sunday. Andy K3UK On Sat, Aug 21, 2010 at 5:05 PM, raf3151019 wrote: > > > Hello Andy, > > It was interesting reading the description of the half square antenna you > made, particularly the comments on the comparison between vertical and the > half square. Being unable to hear European stations may partly explain why, > when conditions do improve a little, I always keep seeing the same PSK > stations from the US, and the ones which can see me on their screens are > most often very weak to my QTH > > Considering the huge number of PSK users in the US I've often wondered if > my R5 is "deaf", or lots of US operators are using wet string ! > > Regards, Mel G0GQK > > >
Re: [digitalradio] Re: Good USB sound card ?
On 08/14/2010 02:15 PM, g4ilo wrote: > Well, that isn't my experience. Regardless of the chip set used, it's the > entire product including the drivers that will determine the performance. > > My suspicion is that these devices run at a fixed sampling rate, and that > resampling to the rate requested by the software is carried out by the > drivers. Not an issue for me since I run Linux and fldigi. The digital mode program fldigi simply gets the audio off the device at one of the native sampling rates of the device and does good quality sample rate conversion internally. I believe you if you have seen the Windows drivers for the device do a terrible job of sample rate conversion. However, I'm not going to experience that issue myself and am quite happy with the device in my setup :) > Personally I don't think it is worth economizing in this area. That I can agree with. -- All rights reversed.
Re: [digitalradio] Re:Streetlight RFI found with AM portable
A trick that you might try is that when you find an offending pole, give it a good whack with a sledgehammer to see if the noise changes. We tracked down a couple of poles that were throwing some serious RFI out, and that's how the power company guy verified where the problem was. Seems that the pole was put in in the 40's, and the rest of the hardware was about the same age. On 8/21/2010 1:09 PM, Tony wrote: > > > Paul, > > That's a nice rig to have. I understand it's capable of AM mode as well > - add a small hand held 2 meter Yagi and you'll have one FB direction > finding RFI detector. > > Tony -K2MO > > >> I live near the Atlantic Ocean in "Slower Lower" Delaware. Our problem >> here is that during dry weather, we get salt spray on the power lines >> and transformers, leading to all sorts of noise. A good rain helps. >> >> I have a small Yaesu VR-500 wide band receiver. It works very well for >> tracking down RFI/EMI around the house as well. Good way to find >> offending "wall warts," and the like >> >> /paul W3FIs
Re: [digitalradio] Re:Streetlight RFI found with AM portable
On 8/22/2010 2:04 AM, John Gleichweit wrote: A trick that you might try is that when you find an offending pole, give it a good whack with a sledgehammer to see if the noise changes. We tracked down a couple of poles that were throwing some serious RFI out, and that's how the power company guy verified where the problem was. Seems that the pole was put in in the 40's, and the rest of the hardware was about the same age. I've heard about this John - makes sense. Tony On 8/21/2010 1:09 PM, Tony wrote: > > > Paul, > > That's a nice rig to have. I understand it's capable of AM mode as well > - add a small hand held 2 meter Yagi and you'll have one FB direction > finding RFI detector. > > Tony -K2MO > > >> I live near the Atlantic Ocean in "Slower Lower" Delaware. Our problem >> here is that during dry weather, we get salt spray on the power lines >> and transformers, leading to all sorts of noise. A good rain helps. >> >> I have a small Yaesu VR-500 wide band receiver. It works very well for >> tracking down RFI/EMI around the house as well. Good way to find >> offending "wall warts," and the like >> >> /paul W3FIs
