September 2001 THE SQUELCH BURST a monthly publication of the STAMFORD AMATEUR RADIO ASSOCIATION President ..........Jim Murdock ............ N1NNG ........ 322-4707 Vice Pres ..........Andy Laska ............. KA1SLG ....... 531-9493 Secretary ......... Mike Cordelli .......... N1FOA ........ 838-3661 Treasurer ......... Dick Finn ...............WA1VUU ....... 323-0982 Trustee ........... Spence Heath ........... W1BWK......... 322-7539 Editors ........... Marv Fleischman ........ N1AWJ ........ 438-7889 Mike Cordelli .......... N1FOA ........ 838-3661 Dick Finn ...............WA1VUU ....... 323-0982 Y.O.J.B. Ed........ Marv Fleischman ....... N1AWJ ........ 438-7889 Circ/Pub. ......... Dick Finn .............. WA1VUU ....... 323-0982 Repeaters: W1EE/R........ 146.055 in; 146.655 out (PL. 1Z, 100Hz) W1EE/R.... 442.125 in; 447.125 out (PL. 2A, 114.8Hz) Internet Home Page at http://www.qsl.net/w1ee/index_ns4.html Yearly membership $15.00 ($ 10.00 for retirees, senior members over 62 , full time students, members under 16 years of age and members living over 100 miles from Stamford; $20.00 for family memberships.) This includes a copy of the club bulletin and a copy of the club roster. Send your dues, membership applications, etc. to the club Treasurer , Dick Finn, WA1VUU, 27 Ivy St., Stamford CT 06902. Non-commercial ads are printed in the SQUELCH BURST on a no charge basis, club members only. Send your ads for Ye Olde Jonque Boxxx and articles for the SQUELCH BURST to Marv Fleischman, N1AWJ, P.O. Box 113, Ridgefield, CT 06877, or e-mail to n1awj@ att.net. Meetings are held on the first Thursday of every month in the 4th floor cafeteria of the Stamford Government Center, Tresser and Washington B'lvds., Stamford, CT. Meetings start at 8:00 P.M. PRESIDENT'S MESSAGE Bill, N1NOA, has been a member of SARA for 9 years. He has never been very active in the club because he has been involved in his studies of artificial intelligence. Last month Bill received his Ph.D. from Georgia Tech. I'm going to let him describe his current research: Human beings are tremendously effective at adapting to novel, unexpected situations. Compare a human logging information for QSL cards versus a QSL recording program on a computer. The program may be able to perform millions of computations per second, vastly more than the human can. However, even a very minor change to the format or organization of the information that the program receives will typically render it unable to do anything at all. For example, if the QSL recording system is designed to accept a set of numbers and strings (such as contact names, frequencies, etc.) separated by commas and it receives this information separated by spaces, it will simply fail. In contrast, a human operator would have no problem dealing with such a change. We hypothesize that this human ability is derived, at least in part, from the human's comprehension of his or her own reasoning. A human working on some process understands the goal of the process, the techniques used to accomplish the goal, and the nature of the information that is used to support those techniques. In this example, the human knows that the numbers and strings represent information about a radio contact and that the commas were present merely to separate the numbers. This information is also present implicitly in the QSL program . However, the information is not represented in a way that the program can manipulate and alter. Furthermore, the program has no procedures for performing such alterations. Thus, unlike the human, the program is not able to infer that the spaces in the new records serve the same purpose as the commas in the old records and that the numbers in the new records should simply be used in the same way that the numbers in the old records were. The issue of how to enable a software system to adapt to new challenges using an understanding of how it works is the focus of my Ph.D. thesis. The title is "Self-Improvement through Self-Understanding: Model-Based Reflection for Agent Adaptation." In order to do this research I had to write an operating environment called REM (Reflective Evolutionary Mind) . REM has three major aspects. The first aspect of REM is a language called TMKL (Task-Method-Knowledge Language). This language allows encoding of systems which can reflect on their own reasoning including the tasks that they perform, the methods they use to accomplish the tasks, and the knowledge that supports the tasks and methods. The second aspect of REM is an interpreter, which executes systems encoded in TMKL. The third aspect of REM is a set of adaptation strategies, which make changes to TMKL systems. The combination of these capabilities provides a framework for writing and using software that is able to adapt to novel circumstances. Bill is continuing his research at The Naval Research Lab in Washington, DC 73, Jim, N1NNG. ASK ELMER Dear Elmer, I have come across a rather strange phenomenum. I have a 7 AH 12 volt gell cell battery and it was due to be charged. I tested the battery with my digital meter. The way I charge the battery is with a wall wort battery charger. I measured the voltage of the charger and it read 17.89 volts and the battery read 11.72 volts. After I connected the wall wort to the battery I decided to take another reading. This reading gave me quite a surprise. I was expecting to read either the higher voltage of the wall wort or something in between the wall wort and the battery. Instead, I got a reading almost exactly as that of the battery, 11.75 volts. The question is, why do I not get the same reading at the wall wort, 17.89 volts? At least I know that I can run a radio from the battery even though I have the battery hooked up to a charger with higher voltage that the radio should have presented to it. By the way, I got the battery charged up to slightly over 14 volts and disconnected the charger. Now I am running it back down again. Ain't life grand? Befuddled Dear Befuddled, To properly answer your question we have to discuss the some of the charasteristics of rechargable batteries and in reality, batteries in general. A battery consists of a group of cells connected in series. Each cell has a terminal voltage which is determined by the cell's chemistry, i.e., a Nickel Cadmium cell has a terminal voltage of 1.2 volts, a Lead Acid cell has a terminal voltage of 2.0 volts, etc. This terminal voltage is just a nominal voltage, and does vary with the cell's state of charge. A Lead Acid cell at full charge can exhibit a terminal voltage of 2.35 volts, and 1.85 volts at full discharge. Associated with each cell is an internal resistance caused by the materials used in the cell as wel l as its chemistry and its construction. If the cells are in good condition, this internal resistance is fairly small, making the battery look like a constant voltage supply. A constant voltage supply is one whose terminal voltage does not vary with changes in current drawn from it. (The I X R voltage drop which would be predicted by Ohm's Law. Where R is the internal resistance of the battery and I is the current being drawn from the battery.) Now we must look at the characteristics of the plug-in "Wall Wort' power supply. Most of these supplies consist of a transformer, a full wave bridge rectifier and a single capacitor to supply a filtered DC to power an electronic device. These power supplies are not voltage regulated, so their ratings are given at a specified current, i.e., 12 V @ 100 mA, etc. When unloaded, these power supplies exhibit a terminal voltage which can be considerably higher than their rated voltage due to their relatively large internal resistance (much more than that of a battery). The reason for this relatively high internal resistance is the effective resistance of the transformer, the diode bridge's resistance and efficiency in converting the AC to pulsating DC and the size of the capacitor storing the resulting DC. We can now discuss the measurements you made on your charging system. The 17.89 volts you measured as the open circuit terminal voltage of the "Wall Wort" is the peak voltage stored on it's capacitor. As this is a peak voltage, multiply it by 0.707 to obtain the RMS no load voltage output of the transformer (I am neglecting the small voltage drop in the diode bridge rectifier) . This gives you 12.65 volts out of the transformer. This generally means that at the "Wall Wort's" rated current, its output voltage would be 12.6 volts , and would be lower if the current being drawn from it is higher. Again this is the I X R drop due to the internal resistances predicted by Ohm's Law. Since the battery's terminal voltage increases with its increasing state of charge, the amount of current supplied by the "Wall Wort" is steadily decreasing, as it is limited only by the "Wall Wort's" internal resistance (Ohm's Law in action). This is why you measured 14 volts when the battery was at full charge. At this point the battery's terminal voltage would not increase significantly, as it is fully charged, and any additional charging would just cause the battery to get warm due to overcharging. At this end of the charging cycle, the battery should be removed from the charger, or the charging current be reduced to a maintenance trickle charge. I have to admit that you have been extremely fortunate in your choice of battery charger. Because small "Wall Wort's" have a relatively high internal resistance, you have not overcharged the battery by exceeding its maximum charging current, nor over-dissipated the "Wall Wort" causing it to fail. For some additional information on batteries and charging, I would suggest reading chapter 11, pages 20 through 23 in " The Handbook for Radio Amateurs, 2001" by the ARRL. I trust that your question has been answered to your satisfaction, and you are no longer Befuddled but "Charged Up" with knowledge. 73, Elmer Send your questions to ASK ELMER, c/o Marv Fleischman, N1AWJ, PO Box 113, Ridgefield, CT 06877-0113 or e-mail them to n1awj@att.net. REGISTERING ON THE FCC's ULS Many of our members are uncertain of the method of registering with the FCC's Universal Licensing System (ULS). Fortunately, the FCC's web page has been updated to make negotiating their site relatively easy for the initiated. Registering in the FCC's ULS is necessary in order to conduct any business with the agency which includes change of address, renewing your license, etc. The FCC did not transfer their amateur radio license database into the ULS, but left that process up to the individual licensees. They do require some additional information, your Social Security Number (SSN), to help the IRS track tax evaders (you can thank your congress for that piece of nonsense). Everything, except your SSN is made part of the public record, available to all. The FCC will issue you a License ID number which you can use on documents in place of the SSN. To register, log onto the FCC's website, http://www.fcc.gov. On the upper left side of the web page, click on "E-Filing". On the E-Filing page, scroll down to "Universal Licensing System" and click on it. Then click on "Register - TIN/Call Sign". Simply follow the on screen directions and you will be registered. They will ask for your telephone number and e-mail address. If you wish to keep this private, you need only enter a "0" in these fields, as they are not required, but must have an entry. Once registered, with your own password, it will echo back your information, and issue you your "License ID". Thats all there is to it. I am uncertain, but I think the FCC will then transfer this information to their new database called "CORES", and issue you an FCC CORES Registration number by mail. This was the way I received my CORES number. If you upgrade your license, you will automatically be registered into the ULS and CORES system, but the FCC issues the password. In order to get the password changed to one which you can use , you have to contact the FCC by phone for a temporary password good for 24 hours. Then go into the FCC's site and change it to your own. To do this you have to telephone their Gettysburg office, but that is another story (see the April 2000 issue of the SQUELCH BURST article by Tim Walker). 73, Marv, N1AWJ YE OLDE JONQUE BOXXX DENTRON GLA-1000B Linear, VGC, $350; ICOM IC-2AT 2m HT w/ Charger, Batty, & ss-32MP micro-min. CTCSS encoder kit, VGC, $100; Simpson Model 260 VOM, VGC, $50. Call Geoff, N1CAT (203) 966-7444 evenings HALLICRAFTER SX-28A RECEIVER, recapped, $275. Works good. Call Joe, N1GWO, (203) 322-4061 Evenings ESTATE SALE: ICOM IC-734 HF w/Mike, VS-20 P.S., $ 805; MFJ-16010 Antenna Tuner, $ 30. Call Jim, N1NNG, (203) 322-4707 PARTS GALORE- Xerox 3000 Word Processor (antique) w/transformer, p/s, etc., connection to Diablo printer. FOR FREE!!! Take it away! Call Mike, KA1VWP, (203) 838-8089 AOR 1000 XLT, 1000 Channel HH Scanner, 5KHz to 1.3 GHz continueous coverage. Exc. cond. $ 275. Call Rick, N1LYK, (203) 531-1756 YAESU FT-757 GXII, HF Rig, FP 757 HD Power Supply, FC 757 AT Tuner and MD 1B8 Desk Mike. Call George, N1HIX, (203) 357-1879 COMPLETE HF STATION, will sell all or part: Kenwood TS-820S, Remote VFO, MC-50 Mic, Dentron Linear Amp., Mosley TA-33, Ham-M Rotor, Roof Tower, MFJ Antenna Tuner, SWR Bridge, Phone Patch, etc. For details please Call Fred, K2RUR, (203) 325-2201 ICOM IC-25A 25W , 2M mobile Xcvr. w/PL, good for packet $75 obo. ICOM IC-02AT with BP-5 and BC-30 charger, Exc. Cond. $120 obo. Mac Imagewriter & Laserwriter printers, best offer. Call Jeanine, KY1Q, (203) 324-6865 APPLE PERFORMA COMPUTER....... Really Cheap Call Andy, KA1SLG, (203) 531-9493 CUSHCRAFT R5 VERT. ANTENNA: Wind Damaged and attached to my garage. Help me take it down IT'S YOURS, FREE!!! Call Frank, KA1NTG, (203) 655-7378 ICOM IC-02AT 2M HT w BP-3, BP-5 & BP-8 Batty Packs, BC30 Charger, Spkr-Mic, Manual, $125 obo. FatMac Computer w/ 1Meg Ram, best offer. FOR PARTS..Olevetti Accounting Machine. FREE!!!!! Take it away!!! Call Marv, N1AWJ, (203) 438-7889 ROTOR w/CONTROL & CABLE, $50; Cushcraft 10-40M Vert. Ant., $15; Ringo Ranger 2M Antenna, $10; Heathkit Station Monitor Mod. 614, $50 . Machinist's Tools for Sale, 2 South Bend 7.5 HP Go-Cart Engines. Lots of Tools, Hardware and Craft supplies, etc. Call for Info. Call Irv, N1ATS, 348-3425 BIRD MODEL 43 THRULINE WATTMETER, 2 Elements & RF Sampler; Mirage B23A 2M 30 Watt Amp,; MFJ 1000W Dummy Load; Transi-Trap Surge Protector Device. All like new. $100 takes it all! Call Greg, N1DSK, (203) 322-9250 Send all your ad's for YE OLDE JONQUE BOXXX to Marv Fleischman, N1AWJ, PO Box 113, Ridgefield, CT 06877. E-mail to n1awj@worldnet.att.net. Ad's must be in by the meeting night of the month prior to the publication. (December meeting for January publication) EASTERN SLOW SPEED NET Join the Eastern Slow Speed CW Net every evening on 3590 KHz at 6PM local time. CW speed is between 6 and 8 wpm. A great way to improve your CW proficiency and learn net operation. Joe, W1LUH is one of the rotating Net Control stations. STAMFORD DENMARK FRENDSHIP SAILBOAT RACE We still need a few more Volunteers for the Stamford Denamrk race. The positions are both on the water and as standby operators in the event a scheduled operator can't participate. The race takes place on Sunday, September 9, 2001. Call Jeanine, KY1Q at (203) 324-6865 TREASURER'S REPORT AS OF 13 AUGUST 2001 INCOME EXPENSE Donation 100.00 Phone 17.20 Dues 60.00 Repeater 224.84 Interest 9.99 Postage 34.00 Totals _______ _______ $169.99 $276.04 Balances: Checking-$1,085.72 Savings-$4,587.37 de WA1VUU