CCDX Propagation CCDX Propagation The Official Newsletter of the CCDX Amateur Radio Club Where "Radio Active" Amateurs Meet CCDX Back from the Summer Break! Welcome back to the CCDX Amateur Radio Club. Field Day was fun back in June. The new location was a blast! For those that missed the meeting in September We have made a few changes in the club. See the minutes later in the newsletter. Speaking of the newsletter We need some volunteers to submit articles for it. I took it upon myself to produce the first one as there was talk about it at the last meeting. What better way to get interest than to just do it. I will publish it monthly if I get some help by the membership in submitting articles. Don't be shy, we will help you every step of the way in the process. I hope to have articles submitted by many members on varying topics of interest. I know some are interested in contesting and other CW. Some are only interested in HF while others are into satellite communications. Let's hear about your experiences or even construction projects. I hear that Jim, KB1NXE, might have some construction photos, stories and tips for tower building. Neal, AE1P, probably has some homebrew antenna designs he would like to share with us. Others probably have some insight into remote base set up. I hear Dan, W1NAC, is interested in that. de KA1VGM Next CCDX Meeting: October 20th, 2010 Swanzey Police Department 34 Eaton Road Swanzey, NH 03446 (Red Cross is NOT available.) P. 1 2 3 4 5 6 7 8 Article Back from Summer Break Digital Sound Card Interface Sound Card Schematic More Digital Modes Future Topics Minutes of the Previous Meeting Agenda for October Meeting / Program Newsletter / Club Information Page 1
Digital Sound Card Interface by Larry Levesque KA1VGM There are too many digital modes available to the ham today to count. Most don t require any special hardware to interface to the radio. Although one of the most fancy interfaces sells for over $200.00, you can build an equivalent interface for less than $30.00. The most basic sound card interface is to use acoustic coupling. You use your computer speakers and microphone to hear and listen and you manually key the radio. No money needed. Not too good for prolonged use. Not useful at all for error correcting data modes as the transmitter needs to key via the software to make this work. You can also use direct connect cables from the speaker/microphone to your rig. We do not recommend this due to feedback and ground loops that can be annoying and damage equipment. If you plan on using this method, we strongly suggest getting a low cost ($3 $15) USB sound adapter. This way you don't damage the sound card in your computer. The safest bet is using audio transformers to couple the microphone and speaker connections and either a opto coupler IC or a reed relay to key the radio. We have included such a schematic in this newsletter. You can build your own sound card interface and save some major money. We found the parts via Radio Shack, Mouser and Digi Key for less than $15.00. Add an enclosure, wire, solder and a little bit of sweat and you will have yourself a digital interface in no time. There are plenty of hams in the area that can help you get started in digital modes over amateur radio. Rumor has it that some are actually playing with it during the weekly ARES nets and on the simplex frequencies on 2 meters. Give a call on one of the local repeaters and see if anyone is available to play around on digital. It is amazing to see how much information you can send back and forth in a short time. Using one of the error corrected modes, you can be sure the other person receives your message 100% intact. Try that with a voice net and then multiply that by 15 different people asking for fills and the power of digital becomes something you won't want to live without. Page 2
Sound Card Interface Schematic Please note that although this schematic appears small when viewed at 100% magnification, it was saved at a much higher resolution. Increase your PDF viewer's magnification to ~200 300% to view all the detail. Page 3
More Digital Modes! How long do you think it would take you to send the spreadsheet below over a 2 meter repeater to another amateur 100% error free? Now imagine that was a list of medicine needed for a hospital. (Ever notice how close those drug names are spelled? A couple mistaken letters could mean the difference between life and death for someone.) Now how about sending the spreadsheet to 10 other hams? 10 minutes not likely! Try more like almost one half hour not including fills. And can you really be sure it's 100% error free? Would you bet your life on it? Enter a digital mode. For this instance we will say PSK500 using the programs fldigi and flwrap. Fldigi is a digial mode program. Flwrap actually "wraps" the file with a checksum. The receiving station or stations can verify afterwards that they received it 100% exactly how you sent it. PSK500 time to wrap the file, send the file, receive the file, unwrap the file (to prove 100% error free), print out and forward via email just over 1 minute. (Actual transmit time to send the file over the radio: 22.3 seconds) Yes we tried and timed both methods! Page 4
Topics We Plan on Covering in the Near Future: by CCDX Leadership Let us hear what you want to learn more about: Are you interested in talking through a satellite? How about to the International Space Station? How about bouncing a signal off the moon to talk to someone half way around the earth? How about communicating so fast that it happens in the time it takes a meteorite to burn up in the atmosphere and using it's ionized trail for the propogation path? Are you interested in fox hunting? How about contesting? How about building you own radios? Building your own antennas? CW Morse Code? Slow Scan TV? Fast Scan TV? Digital Voice? AM? 6 Meters? 160 Meters? Packet? APRS? Remote control of your station? Free Software? Operating Systems? Whatever your interests are, let's explore them and more. That is what the CCDX Amateur Radio Club is all about. Choose a subject related to amateur radio, and we will cover it in the coming months. We are going to need your help deciding what to present. We might even need your help with presenting a topic. Please feel free to present any ideas regarding content for meetings to the club. While we cannot promise all topics will be covered, we will do our best to make it happen. Page 5
September 2010 Minutes of the CCDX Meeting September 15, 2010 19:00 Meet and greet. All present stated Name, Call sign and hometown. Discussion on elections, Elected were as follows, President Larry Levesque KA1VGM Secretary Derek Tousley W1WWW Treasurer Mike Paulin N1MXJ A discussion was held on Bylaws. Accounts and a repeater committee. Motion to create a repeater Committee. Dale Paquin N1NCI has accepted a posting on said committee. Motion to ask Arnie Johnson and Joel Huntley to be on the repeater committee. Motion to study Bylaws before acting on previously mentioned Motions. Discussion on an Advisory group. Discussion on the status of Henry the K1TQY repeater. It is on the bench and needs parts. Bruce Bohannon discussed the Clarence Demar Marathon. Larry Levesque talked about the Reach the Beach relay race, Maybe visiting other clubs and also a TriCounty Net using the Mt. Ascutney 146.760 repeater. Discussion on possible dues increase to be tabled for future meeting. Loose discussions on Newsletters, Fundraisers, CCDX reflector and Email updates. Larry asked for requests for events or interests to be included in future meetings. Motion to adjourn At 20:20 accepted. Page 6
CCDX Amateur Radio Club Meeting Agenda 7:00 PM Type of Meeting: Monthly Meeting Meeting Facilitator: Larry Levesque KA1VGM Invitees: All CCDX Club members and the general public I. Call to order II. Roll call III. Secretary's Report Approval of minutes from last meeting IV. Treasurer's Report Quick accounting of current funds available. Opening of new accounts. V. Open issues a) Repeater Committee See if Joel and Arnie are willing to participate and brief report if available. b) Discussion on make up of advisory group suggest general membership. c) Clarence DeMar Marathon Report Bruce Bohannon d) Studying of existing ByLaws and proposed changes VI. New business a) Web Site status report b) Programs Committee c) Field Day Committee d) Asset list e) Additional?? VII. Adjournment The monthly business meeting wil be followed by a monthly presentation / program. This month Larry Levesque KA1VGM will give a presentation of Flidigi. Fldigi will be used as the primary traffic handling mode in the upcoming NHARES SET on November 13th. The presentation will discuss the newly added freatures to the program and how it will be used during the SET. We ask that you bring a laptop and power cord with you to the meeting if you can. We will provide the means to download the version of Fldigi that we will be using during the SET. We will also have a hands on session. Attendees will use the "acoustic coupling" method to send messages back and forth to each other. No radio or sound card interface will be required for this demonstration. Page 7
The CCDX Amateur Radio Club Newsletter is the official publication of the Cheshire County DX Amateur Radio Club. We are looking for articles to fill the monthly newsletter. The CCDX Amateur Radio Club is currently represented by the following elected officials: Please send all submissions to ka1vgm@gmail.com. Treasurer: Mike Paulin N1MXJ We prefer all submissions be in a standard "editable" format such as MS Word, OpenOffice, RTF, txt, etc. We will not accept PDF files that have been scanned due to not being able to export the text. Please make sure it is your original work and all external sources are referenced in your submission. President: Larry Levesque KA1VGM Secretary: Derek Tousley W1WWW These elected positions are voted on by the current membership during its annual meeting in September of every year. A copy of the incorporation documentation, position responsibilities, membership requirements, minutes of meetings and more can be found on our website at http://www.ccdx.org This newsletter is designed to be 100% digital. No enhancements were made to allow for better looking printed text. Where necessary, digital images are saved in a higher resolution. This allows for better viewing at magnified levels on screen. This is especially important for schematic drawings. The original material is acknowledged to belong to the author. By submitting the material for inclusion into the CCDX newsletter, the author is authorizing the CCDX ARC the use of the article. This use may include re printing the specific article and posting on the CCDX web site. This newsletter was created using 100% Free and Open Source Software. Graphics creation: Gimp Typesetting/Desktop Publishing: Scribus Schematic creation: gschem Spreadsheet: OpenOffice.org Editor / Publisher: Larry Levesque KA1VGM ka1vgm@gmail.com Page 8