The November meeting will be. Occasionally, we will see powers represented as dbm numbers, and. Decibels demystified part 3 Bob W1ICW ELECTIONS N V

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1 adio maeurs of orhern erm on adio maeurs of orhern erm on adio maeurs of orhern erm on ovember 2011 n L Special Service Club ol. 21 o. 11 ex Meeing: Broadcasing The ovember meeing will be somehing a lile differen. We are pleased o have Marselis Parsons as our speaker. Marselis is he former ews Direcor of WCX-T and served for many years as he nchor of he Channel 3 ews a 6 p.m. Marselis has now reired from he daily grind, bu he will never be done elling sories. He will be elling us a lile bi abou he hisory of broadcasing, bu no from he echnical side. This is sure o be an enjoyable and fun evening. ELECTIOS Don forge o bring in your ballo! You should find one for each member in your household insered in his newsleer. The slae is se as follows: Presiden: Bob llen KB1FW Wrie-in: P/Treasurer: Carl Dow B1DD Wrie-in: Secreary: Jeff Bonn 1YD Wrie-in: December Meeing o deails a publicaion. The nnual Holiday Pary is scheduled in place of he usual meeing. ll are welcome! You re requesed o bring somehing for he po-luck so sar hinkin on i, and keep your eyes and ears peeled for dae/ime/locaion/oher deails. Decibels demysified par 3 Bob W1ICW db, dbm, SID, and ssg...oh my! Occasionally, we will see powers represened as dbm numbers, and here is a lo of confusion surrounding his erm. Simply pu, 0 dbm is a finie power level, meaning 0 db referenced o a milliwa. So 0 dbm = 1 milliwa of power. Tha s 1/1000h of a wa. +10 dbm would be en imes ha or 10 milliwas, or 0.01 wa. +20 dbm would be 100 imes a milliwa (100 milliwas), or 0.1 was, and so on. dbm is simply anoher way of referring o power. I is ofenimes a lo simpler o say in dbm if we have a lo of gains and losses, and hen conver he ne resul back o was a he end. For insance, say I have a ransmier ha pus ou 100 was, a feedline ha loses 3 db, and an anenna gain of 6 db. Insead of having o use he db formula (10 log b/a) hree imes, we conver he power o dbm once, do he addiions and subracions, and conver back, and we never have o ouch he log buon on our calculaor. Le me show you. 100 was = 100,000 milliwas (since 1 milliwa is 1/1000h of a wa) so i is +50 dbm (remember, 50 db is 1 followed by 5 zeroes imes he power). Then we lose -3 db in he coax, so we are down o +47 dbm (+50 minus 3 db loss), hen we gain +6 db a he anenna, fora ne resul of +53 dbm. We know his is +3 db above +50 dbm so i should be double he power, or 200 was. When all is said and done, we have effecively doubled he power of our 100 wa ransmier wih his anenna sysem. emember db is a value of CHGE up or down, while dbm represens a finie power level. I's like saying, I have so many was of power. ll he same rules of decibels we used above apply when using dbm. So, if for insance I waned o know how many dbm 5 was of power is... I know 1 wa is 1000 milliwas of power, or +30 dbm. I also know ha en imes ha is 10 was, or +40 dbm. So half ha should be +40 dbm minus 3 db, or +37 dbm, = 5 was. While hese values are no perfec, hey are sure as heck close enough. If you really wan EXCT values, you can eiher break ou your scienific calculaor, or use one of he many online converers. One good one is here: power-o-dbm-conversion.hml We have all looked a he specs for he laes YaeComWood gee-whiz gadge on he marke and drooled over is new feaures, or exra bands or wha-have-you. Someimes we will even go so far as o check he receiver specs, which are usually expressed in SID for a paricular microvol level, usually somehing like.25 microvols for 12 db SID. The smaller his number is, he beer he receiver Coninued, page 3

2 adio maeurs of orhern erm on adio maeurs of orhern erm on : Secreary s epor Jeff 1YD, Secreary Ocober Meeing Business: The meeing began wih elecions. Bob llen KB1FW was reeleced as presiden, Carl Dow B1DD was reeleced as reasurer, and I was reeleced as secreary. Welcome o new hams Jeremy KB1WDM, and Kahi's un Bey, who passed he Technician exam, bu whose call sign was no known a meeing ime. [Ed: Bey s call is kb1wdn] Kahi will bring snacks o he nex meeing. Presenaion: SKYW Greg Hansen from he aional Weaher Service spoke o us abou SKYW. The aional Weaher service has 122 offices across he counry. Greg works ou of Burlingon Inernaional irpor. Some of he WS producs include oulooks, waches, and warnings. WS runs he Emergency ler Sysem o announce severe weaher like ornadoes, hail, and srong wind. (The sae ges abou one ornado per year.) Hisorical weaher daa is available a he IEM Cow sie, which has nohing o do wih dairy animals. The WS uses 5 o 10 cm radar o deec sorms. The sae is covered prey well excep for pars of he orheas Kingdom. The main WS websie for our area is www. weaher.gov/bv. long wih curren condiions and forecass, i provides a way for he public o repor a sorm. eporing by he public is useful because i provides ground ruh. The repors help o calibrae he radar images vs. acual evens, and o confirm severe weaher repors. epors from areas ha do no have good radar coverage are also quie useful. Some observers sen in picures of omao-sized hail, which was prey cool. To repor a sorm, conac WX1BT on , weaher.gov/bv, or call If you would like o se up your own weaher saion, describes how o ge sared. Sepember Meeing Business: E-Fes X will be on Friday and Saurday (Ocober 14 h and 15 h ) a he Deerfield Fairgrounds in Deerfield, ew Hampshire. I s really good. If you are ineresed, discoun ickes will be available a our nex meeing. Our nex meeing is no o be missed. We will have elecions and Paul will bring snacks. Wha more could you wan? Jus show up and you can score some Oreos and become a club officer. umour has i ha he posiion of club secreary is open. Bob Brown, W4YFJ, described his work during Tropical Sorm Irene. The flooding was quie differen from he usual calls and emergencies ha he handles. There was very lile ha anyone could do as rising waer slowly desroyed homes and buildings. Ham-Con will be February 25 h a he Holiday Inn. The admission fee will be he same as las year. Mich urged us o use he repeaer. Pu a radio in your car, and urn i on. Presenaion: Mich W1SJ described HF conesing, or Mounainopping. The HF bands are more or less line of sigh, so he only way o compee a a high level :-) is o se up your saion on op of a suiable mounain. Some of he key facors are elevaion, populaion, vehicle access, and noise level. Moun Mansfield is noisy, Moun Equinox has a valley oward ew York ha is quie good, and Moun Washingon is no close o major populaion ceners. mounain ha can reach ew York Ciy, and lbany is especially favorable. Moun Equinox seems o be he bes. On 2 meers wih a 20 db gain anenna, miles is possible. Mich reached irginia once. You will have o bring your own power. Baeries are OK for QP, bu anyhing more needs a generaor. Bring a able and chair, or plan o be uncomforable. Mich ses up an elaborae array of anennas using a drive-on moun and a second, guyed, mas. Plan ahead he anennas have o be somehing ha you can handle yourself in wind, rain, and oher difficul condiions. Mich akes his suff seriously. His approach is one radio per band. Tha means radios for 2, 6, and 10 meers, also 440MHz FM, 2 meer FM, 222 MHz, 903 MHz, 1.3 GHz, and 3.4 GHz. He also brings backups. Each mas has an anenna roaor. ll of he radios feed ino an audio mixer and one se of headphones. ny such conesing rip can urn ino a survival excercise. Bring los of supplies and be prepared for wind, sun, cold, rain, ec. Mich is convinced ha caamouns are no really exinc because he saw one,and i hissed a him. In general, be careful. ovember 2011

3 adio maeurs of orhern erm on adio maeurs of orhern erm on FIELD DY 2011 WE ELLY KICKED BUT Mich W1SJ Since las Field Day, viewers of our web sie have seen he heading, Field Day 2011 We Kicked Bu. We submied a massive score and were proud of he resuls of our effors. Wha we didn know a he ime was who else pu up a massive score, besing our effors. Wih he publicaion of he Field Day resuls, ha has been decided. We have repeaed as winners in he Field Day 2 caegory. Congraulaions and grea job everyone! I was very surprised a how far ahead of he pack we were by some 2500 poins. I ruly expeced i o be a real horse race as he compeiive Field Day groups faened up heir scores wih grea openings on 6 and 10 meers. noher noable accomplishmen is ha we were repea winners. While here are some dynasies in he higher ransmier caegories, repeaers are much fewer in he super compeiive 2 caegory. Our forerunner, known as he Silicon Juncion adio Club, operaing as K1T, did i way back in W5 did i in and W6PT did i in K5DX won in wo non-consecuive years (90, 97). Going back 25 years, our group and forerunners opped 2 a oal of 7 imes. Bu wha was even more amazing was ha wih poins, we besed a 2 scoring record which sood for 18 years! In 1993, a group of cones operaors assembled in he irgin Islands and amassed an amazing score (in hose years) of poins. Tha group was organized by a fellow wih he call sign 2E. nd by he way, Jim also did a couple of CW sins wih us his year, so he is par of he legacy of boh records! Overall, across all caegories we were 11 h. If we had goen a bunch of kids o operae or if we d picked up anoher 50 phone TE METE FIEWOKS Mich W1SJ Jus on he off-chance ha you are locked in mealframed building wih no receiver or anenna available, be advised ha 10 meers is back! Some weeks back, hams repored ha hey were working openings on 10 meers. I finally pu he radio on and he band was wide open. This wasn he ypical in-and-ou Sporadic E opening we have been seeing over he years, bu a full F2 opening. The band was opening up well ino Europe in he morning, coninued open across he U.S. all afernoon, and sayed open several hours pas sunse. nd his has been going on for weeks. If you have been following propagaion news, you know ha sunspos have been on he mos-waned lis. arious heories were proposed by he expers, culminaing in he observaion ha we migh be in a repea of he 18 h cenury Maunder Minimum, where here was no sunspo maximum for 30 years. Then, boom! umerous sunspos appeared ou of nowhere, he bands opened up big ime and a large solar even riggered a massive aurora borealis a couple of weeks ago. So much for predicions by he expers. I is hard o say if hese grea propagaion imes will hang around long. There apparenly is a lo we don undersand. Meanwhile, don wai! Fire up he radio, oss a wire ino a ree, and enjoy he openings. Condiions are such ha low power and small anennas are working he world. I doesn ge beer han ha, so ge on while i lass. nd le s hope ha he condiions hang in here hrough mid-december when we can have a monser ime in he Ten Meer Cones! Coninued nex page HOLIDY PTY DECEMBE 13 h Mich W1SJ Mark Tuesday, December 13 h on your calendar for he Holiday Pary. There ll be pleny of fun, food and good imes o share. We ll have he usual ypes of food available in addiion o he oher dishes which aendees bring. If you have any special requess or would like us o ry somehing differen, le me know. I ll have a survey ou in early December o deermine who is bringing wha. nd since we did so well in Field Day his year, we will celebrae ha wih chocolae cake! nd I m sure pleny of oher dessers will make an appearance oo. Bring a heary appeie! Le s ry o pick up he aendance by geing some new people o join us his year. nd by all means, bring your S.O. oo, as his is a family even. We ll ry o one down he ham radio shop alk! I would be nice o come up wih some new family-friendly aciviies send your suggesions along soon! ovember 2011 Inser

4 adio maeurs of orhern erm on FD con. QSO s, we would have landed 9 h. In erms of oal QSO s, we were a veriable QSO-making machine and finished 4 h. The 3 groups who made more QSOs were running 25, 5, and 3 ransmiers o our 2! There have been a number of discussions on wha our secre is. nd he answer is ha here is no secre jus a lo of hard work and aenion o deail. Our equipmen and anennas are ypical of ha found in any serious Field Day group. nd our operaors, all of whom are very good a wha hey do, are no a who s-who of worldwide conesers (alhough I ry o recrui he big guys every year!). lmos 20% of our oal QSO s were made by non-conesers on he HF and GOT saions! In a cones, he key is knowing he bes band o be on and how o pu more conacs in he log han he compeiion. nd here is he bad news a lo of his is luck! If he propagaion shifs wes, he folks ou in Texas have us for lunch! Wha do we do nex year? Simple we do wha we do bes...se up Field Day and make a lo of conacs. There is always room for improvemen and producing more resuls wih less oil. nd in he 25 years we have been involved in his, hundreds of hams have received raining in he various aspecs of seing up compeiive saions o provide reliable communicaions. Tha s more of a lasing legacy ha any accouning of poins! Don forge your ballo! I's annual elecion ime. eminder: 2011 SET ermon s SET (Simulaed Emergency Tes) is coming up righ afer Thanksgiving. This is he L s annual effor o es our ES emergency capabiliies. I's a cones, of sors, as well, wih scoring on several frons. Scores are repored in QST, and we wan ermon in here! Deails will be ou shorly o DEC s and EC s. Expec o hear direcly from he one in your area. You do no have o be an ES member o play, everyone is welcome. So, mark your calendar for Saurday, ovember 26, 0900 o 1200, and keep an ear ou. ovember 2011 Inser

5 adio maeurs of orhern erm on Member Profile: ich Lang W1ell Kahi K1WL ichard Lang has been a licensed ham for only a couple of years, bu his whole life has led up o i. I was ineviable. ich s original callsign was B1K. He changed i o he vaniy call W1ELL in honor of his grandfaher Edward Lewis Leyh. I was his grandfaher who inroduced him o elecronics. Edward Leyh was a jeweler and engraver by rade and a inkerer by naure. He would build mos of he hings he waned, even fishing reels! He helped se up KDK in Pisburgh, P he firs commercially licensed broadcas saion in he US! Edward was sanding on he roof of he saion when i powered up for he firs ime. He was holding an umbrella and fel his fingers ingling from he F in he air. When he buil a new home in 1918 he had an anenna buil ino he framing so he could lisen o he radio. The floor had acid sains from he baeries ha powered he receiver. ich enjoyed working wih his grandfaher, who encouraged him o ry hings for himself and gave him his experimenal perspecive on problem solving. Togeher hey worked on audio amplifiers and repaired a Hallicrafer HQ-129 ha his grandfaher had acquired. Edward also le ich use his meal lahe (he had o sand on a box o reach i) and sparked an ineres in phoography. ich had an unconvenional and memorable firs conac, alhough no as a ham. s a eenager he would buy miliary surplus gear and ry o see wha i could do. Some of his suff was fairly obscure. He picked up some sor of ransceiver and noiced i was keying every 13 seconds. He erminaed he ransmier using a ligh bulb wired ino he ransceiver. One afernoon, while working on he circuis, he heard a knock on he fron door. Upon answering he found wo men from he army. This was during he Cold War when Pisburgh (where he lived) was ringed by ike-hercules missiles. Every ime ich ransmied, he was jamming a secion of he army s search radar. The wo army men srongly encouraged ich OT o ransmi on his rig anymore. He promised, and removed he oupu ubes. In college ich had a double major in Physics and Biology. fer graduaing he wen o work a Carnegie-Melon, his alma maer, designing compuers for he Compuer Science Deparmen. This was in he mid-1970s when compuers were up and coming in a big way! He worked on some DP projecs involving speech recogniion, and designed he hardware and sofware for a compuer-conrolled recording sudio. fer Carnegie-Melon, ich wen o Digial Equipmen where, over he years, he worked in many capaciies as a Senior Consuling Engineer. One of he mos ineresing was when Florida Ligh and Power, a Digial cusomer, was having problems wih lighning repeaedly zapping heir nework adapers and compuers. ich spen a year working a he Universiy of Florida s lighning lab, hen wen on o se up and run Digial s Lighning Consulan Pracice. In 2009, afer perusing some FCC rules and aking some pracice exams online ich decided o go for his HM license. He passed he Technician, General, and Exra exams a one E session! fer becoming a ham, his favorie rig was a Kenwood TS-820 hybrid mosly solid sae, using vacuum ubes for oupu. I died a horrible deah when he power ransformer wen. He ended up selling he reusable pieces and chucked he res. owadays ich lives in a small aparmen where space and sealh are issues. He has a j-pole in an aic space and runs an linco DX-79 and a 2-meer Icom IC-229. His curren projec is designing and building a 160-6m (and hopefully 2m) ransceiver. He has buil a oron F preamp similar o hose used in radio asromery o use wih i. More abou his projec will presened during upcoming meeings and in he newsleer. Decibels con. Well, occasionally we will see dbm used in place of he familiar microvol numbers. ll you really need o remember is ha -120 dbm is righ around.23 microvols which is decen enough receiver performance for anyone. Here s a handy char if you are curious: wa8lmf.ne/miscinfo/dbm-o- Microvols.pdf Lasly, as a curious hisorical aside, in he EY early days of he Japanese consumer elecronics invasion, hey someimes released receiver figures in somehing called ssg unis, or dbf. These were usually posiive unis, so WTH? Well, insead of using he familiar milliwa as he reference uni, hey used he femowa as he uni of measure. Insead of being 1/1000h of a wa, he femowa is 1/1000,000,000,000,000h of a wa. So 1 femowa= -120 dbm. n ad for a vinage Sansui sereo receiver shows a value of 11 dbf as is sensiiviy spec, or roughly 1.95 microvols. I remember seeing hese weird receiver specs on some vinage Icom gear I had, back when hey called hemselves Inoue Communicaions and ha was a EY long ime ago. Hopefully I helped remove some of he mysery surrounding some erms we use very frequenly as hams. s always, feel free o me if somehing I said doesn quie make sense. 73 de Bob W1ICW ich s oher hobbies beside anyhing elecronic include phoography boh digial and film and waercolor. Like many hams, ich is no afraid o experimen and ake chances o achieve a goal. He is always willing o learn new hings and give em a ry. 3 ovember 2011

6 adio maeurs of orhern erm on ovember 2011 Decibels Par 3 Elecion Ballo Secreary: Sep, Oc Member Profile: W1ELL Upcoming, oices, & Oher Misc : December Meeing Pary : ovember Elecions 11/ SET Sa., 11/26, 9 12 Seering Wheel: 3rd Tues, 6:30-8:30 iney-ine esauran, Taf Corners Dues due? Pay online a T Ham adio Calendar ex Meeing Tuesday ovember 8 7:00 pm O Brien Civic Cener 113 Pachen oad Souh Burlingon Broadcasing