ACORN February 2010 Page 1 of 8

ACORNFebruary 2010

ANDY Club Officers President: Bill Woodhead N1KATVice President: Earle Gilmore N1SVBTreasurer: Ivan Lazure N1OXASecretary: Dick Knight N1NYWTrustee: Norm L' Heureux W1SCM

Androscoggin Amateur Radio Club (AARC)P.O. Box 1, Auburn ME 04212-0001

http://www.w1npp.org/Repeater 146.610MHz No pl tone –

Goff Hill, Auburn Maine Please submit articles, corrections and suggestions by the 16th of the month to David WE1U we1u.david@gmail.com

Table of ContentsComing up …...........................................................................................................................................1ARES/RACES Notes by Ivan N1OXA Androscoggin EC........................................................................2Andy Club Meetings.................................................................................................................................2Secretary's Report by Dick N1NYW........................................................................................................3Circuit of the Month-Overview of Filters by David WE1U........................................................................4APRS Tracking by David WE1U..............................................................................................................5APRS on the air and on the Web by David WE1U..................................................................................6APRS Internet Gateways by David WE1U..............................................................................................7DX News by Earle N1SVB.......................................................................................................................8

Coming up …Crystal Falls Hamfest Saturday February 6th http://www.w1tlc.com/

ARES Net Radiogram Wednesday 10 February 1900EST on 146.610MHz

ARES Meeting Wednesday 17 February 1900EST at EOC

2010 ARRL Maine State Convention and Andyfest Friday-Saturday March 26th and 27th

Portland Area Wireless Association Hamfest Saturday, April 17th http://www.pawa-maine.org/modules/wfchannel/index.php?pagenum=8

2010 MS Walk Lewiston High School Saturday April 24th

http://walkmem.nationalmssociety.org/site/TR/Walk/MEMWalkEvents?fr_id=13331&pg=entry

ACORN February 2010 Page 2 of 8

ARES/RACES Notes by Ivan N1OXA Androscoggin ECARES Meeting on 17 February 1900EST at EOC,  Basement of Lewiston Central Fire Station, 2 College Street. I'm scheduling  a on­the­air net on Wednesday 10 February at 1900EST on 146.61. Please have paper and pen so you can copy a message in ARRL format. Also, we will discuss what training should be conducted and what about the Hospital and there Radio's. I'm trying to set up a schedule of radio test of the Hospitals. More to

come. Hope to hear you on the net.

Radiogram http://www2.arrl.org/FandES/field/forms/radiogram2.pdf

National Traffic System  Methods and Practice Manual http://kv5r.com/articles/ham/nts­mpg.asp

Andy Club MeetingsWednesday February 3rd 1900ESTAndy Club MeetingRussel Park Living Center158 Russell Street, Lewiston, ME

Wednesday February 17th 1800ESTAndroscoggin ARES/RACES MeetingAndroscoggin Unified EMA OfficeBasement of Central Fire Station2 College Street Lewiston

Wednesday February 24th 0730ESTMonthly Andy BreakfastRamada Inn, Pleasant StreetLewiston, ME

Wednesday February 24th 1900ESTAndy Club On-air Meeting and Neton the Auburn Repeater 146.610MHz no pl. tone

ACORN February 2010 Page 3 of 8

Secretary's Report by Dick N1NYWThe Androscoggin Amateur Radio Club held a meeting Wednesday January 6, 2010 at Russell Park in Lewiston. In attendance: N1LLU, W1SCM and son Charles, N1SVB, N1NYW, KB1DOI, N1JD, WA1EOJ, N1WFO, and N1OXA.

The meeting was called to order at 7:03 in a different room than usual by Vice President Earle Gilmore N1SVB because the President was absent. Ivan N1OXA made a motion to approve the Secretarys� report as printed in the ACORN. Harold N1LLU seconded the motion. Vote: approved.

Ivan N1OXA gave the Treasurers report, Harold N1LLU made a motion to approve the report, seconded by Andy KB1DOI. Vote: approved.

In old business: Ivan reports that the club received a thank you card from the Russell Park residents council thanking the club for the $100 gift from the club for hosting the Andy Club meetings.

Ivan talked about the hamfest coming up in March and is looking for topics and speakers for the talks. Ivan will be in Australia and New Zealand during the hamfest so we need volunteers to help out.

Rick N1WFO told about his CERT training in triage, and fire extinguisher training.

Ivan reports the next ARES / Races meeting will be on January 20, 2010 at 6PM downstairs at the Lewiston EMA office. Ivan detailed the antenna work that needs to be done at EMA.

Andy KB1DOI moved to adjourn the meeting, Harold N1LLU seconded the motion, Meeting adjourned at 7:32 PM.

ACORN February 2010 Page 4 of 8

Circuit of the Month-Overview of Filters by David WE1UAmplifers,mixers and filters are the building blocks of radio circuits. Oscillators are formed by feeding back the output of a amplifier through a filter. High-Pass Filters (HPF) and Low-Pass Filters can be formed in turn into Band-Pass Filters(BPF) or Band-Stop Filters(BSF) even All-Pass Filters(Phase-Shifters). Passive filters can be designed with combinations of resistors,capacitor,inductors, crystals, transismission lines, mechanical resonators and cavities(ie repeater cans ), without need of external“ ” power and/or active component like a transistor, tube or ic. Active Filters use an active component and external power along with a passive devices. Digital Signal Processing(DSP) systems perform mathmatical functions on a digitized version of the input using an ADC,Analog to Digital Converter.

For starters RC LPF for 3db cutoff of 2500 HzR1=1200 OhmsC1=.053 uF,at 2500 Hz Xc=1200 Ohms)At 2500 Hz half the signal is accoss the R1 and half of the signal is across C1 hence the output is half or 3db down the input. This is ignoring the loading impedences of the input's source and the output's load.

Active Filters isolate these loading influences. The formula for the cutoff frequency is the same, but has gain at cutoff of -R2/R1(negitive to indicate the inverting gain.

Source URLs:http://en.wikipedia.org/wiki/Low-pass_filter

RC Low Pass Filter(LPF) -

RC Filter Formula f in Hertz R in Ohms C in Farads

Active Low Pass Filter provides isolation and - gain

ACORN February 2010 Page 5 of 8

APRS Tracking by David WE1UAutomatic Packet Reporting System (APRS) is used mostly for tracking of vehicles. A GPS receiver is connect to modem and transmitter system set on 144.390 MHz. The modem covers the NMEA-0183 sentences(data) into APRS Packets and generates the 1200/2200 Hz audio tones to be feed into the transmitter, most often via the mic input. Many variations exist, incorpoating some or all of the functions.

APRS Tracker =GPS Receiver + TinyTrak4 Modem + Transceiver on 144.390MHz Or an All in one - -

Kenwood D700 and D710 include the modem just add a GPS receiver

ACORN February 2010 Page 6 of 8

APRS on the air and on the Web by David WE1UAPRS Packets contain a short message with location and other data. Nearby APRS stations with a receiver-modem which can display its location onto a map system, like Xastir(http://xastir.org/) and/or relay(digipeat) the information to extend the coverage.

As useful as tacking is, Bob Bruninga-WB4APR designed APRS as a system for Local Tactical Awareness(check the Source URLs for detailed dicussion). Fully APRS standard compliant client software allows an radio operator to enter and update objects in real-time without GPS. Objects can be events, persons, equipment or information for traveler such as local repeater frequency/pl tones or local Echolink node number. The insert shows Test Objects added by keyboard, a fire, Fire Engine and Tornado ...oh my!

Source URLs:http://aprs.org/APRS-tactical.html http://www.aprs.org/txt/objects101.txthttp://aprs.org/localinfo.htmlhttp://aprs.org/aprs-messaging.html

ACORN February 2010 Page 7 of 8

APRS Internet Gateways by David WE1U Internet Gateways (IGates) link into the APRS-Internet Service(APRS-IS).Sites like http://www.aprs.fi/ can search and display APRS infomation anywhere a internet connection can be made.

http://www.aprs.fi/ displays information from the APRS IS System - Shows the track of Bill N1KAT during the Dempsey Challange October 4, 2009 -

N1KAT 3 was digipeated by- N1WFO 9, KQ1l 3 and KB1PWJ- -

ACORN February 2010 Page 8 of 8

DX News by Earle N1SVBDuring he past month we made 24 DX contacts representing18 different countries. Countries worked in December were:

KV, St. Croix Is.; YV5, Veneuzila; EA8, Canary Is.; ZS4, South Africa; PY2, Brazil; CE6, Chile; PB500, Netherlands; S59, Slovenia; OY3, Faroe Is.; SP3, Poland; Z21, Zimbabway; KC4, Antartica; KH6, Hawaii; TL0, Central African Rep.; PP2, Brazil; 9A1, Croatia; XE1, Mexico; HK3, Columbia;

We did have a one Pacific contact this month. We worked KH6TE in Hawaii. There were a couple of African contacts from countries not heard that frequently. Z21FO in Zimbabway and also TL0A in Central African Republic.

There are several DXpeditions to various parts of the world coming up in February. Some haven t’ been assigned a call as yet or the operators will use the country prefix and their home call.

Feb. 01 to Feb. 28 TI9/ Cocos Is.

Feb. 02 to Feb. 10 J6/ St. Lucia Is.

Feb. 02 to Feb. 15 XU7AFU Cambodia.

Feb. 02 to Feb. 27 XR9JA So. Shetland Is.

Feb. 03 to Feb. 15 E51/ No. Cook Is.

Feb. 04 to Feb. 10 N7I Hawaii

Feb. 05 to Feb. 10 H40/ Temotu

Feb. 07 to Feb. 13 J5NAR Guinea Bissau

Feb. 09 to Feb. 25 TX4T French Polynesia

Feb. 12 to Feb. 25 5Z0H Kenya

Feb. 17 to Feb. 23 V31RR Belize

Feb. 17 to Mar. 10 ZK3/ Tpkelau

Feb. 20 to Feb. 27 VK9X Christmas Is.

Feb. 21 to Feb. 25 S2/ Bangladesh

Feb. 22 to Mar. 03 V88/ Brunei

Feb. 24 to Mar. 17 SV5/ Dodecanese

Feb. 28 to Mar. 13 VP2M Montserrat

ARRL International DX Contest, CW Feb. 20 21, 2010.–

The above DXpeditions are correct to the 10th of the month prior to printing The A.C.O.R.N. For additions after that date, go to my web page and click On the link Reported DXpeditions by NG3K . “ ”

I invite any club members that have a computer to visit my web page. The address is: http://www.qsl.net/n1svb/