SARC Owned and Maintained Repeaters
THE AIRWAVES CALENDAR
From the President's Shack
Well another bout of blustery spring weather has come and gone since the last newsletter. I hope everyone's outdoor items and antennas all survived ok. I sustained some minor damage to a couple of thin wall supports that bent in the heavy gusts we had. All the antennas are still up and working chasing DX when the opportunity presents itself.
Speaking of chasing DX, a bunch of your fellow club members converged on Visalia, CA over in the central valley the last weekend in April to attend the 58th annual International DX Convention. Everyone had a great time and met many of the voices on the other end of DX QSOs we've had. There were presentations on many of the last year's major DXpeditions to places such as Swain's Island (KH8SI and N8S), Lakshadweep VU7RG, Revillagigedo Archipelego XF4DL, Iraq YI9MD, Kermedec Island ZL8R, Montenegro 4O3T and Libya 5A7A. There were technical presentations covering antennas, propagation, operating and other aspects related to DXing. The traditional Saturday night banquet was excellent as well as Sunday's Power Breakfast. There were over $25,000 worth of prizes given away to lucky attendees.
If you haven't been before, I would highly recommend attending. I'll be putting together a small article in the next newsletter showing some of the activities and presentations.
See ya at the meeting. Gene KI6LO
Treasurer's Report as of April 28, 2007:
Draft Account $ 1,275.52 Share Account $ 5,026.26 BALANCE: $ 6,301.78submitted by Pam Evans, KC6UUS
IWV Emergency Net Checkins
April 02 - 14
Thanks Mark, KE6SMA, for net control during the month of April.
Git-R-Done Horse Ride
Greg arrived at the base camp on Panorama Trail about 0'dark thirty on Saturday, found the ride coordinators and collected maps and rider info. These were passed out to John KC6UWM and Lorilyn KG6LEW who proceeded to the northernmost water stop on the first loop, and to Bill WA6QYR, assigned to the veterinary stop to the east of the 9-mile Canyon intersection. The 100 and 75 mile riders were on the trail at 0600 hours with the 50 and 25 milers starting an hour later. The only incidence in the morning was an alert to be looking for two horses that had gotten loose and were missing. They were later found trotting with the group of riders and were recovered. Alex re-supplied water during the event. Fred KG6STR came out after passing his General test at the VE session, and monitored a key water stop on the second loop. Tammy KG6VYA came out in the early afternoon and monitored the Pearsonville water stop, before relieving Fred later in the afternoon. Gene relieved Greg at the base camp at about 1600 hours and, together with Tammy, checked off horses until 0017 hours on Sunday when the last horse passed through the last water stop. No major problems occurred in the evening shift except those due to equipment malfunction (HT batteries dying).
The ride organizers expressed their appreciation for the communications support many times during the event. Two future events (Nov 07) and (Apr 08) are on the schedule and the event coordinators requested our assistance for those. Gene KI6LO agreed that we probably could support those but requested that the coordinators check back a minimum of 90 days prior to the scheduled event to confirm the request to prevent another 11th hour SARC response like this event. They agreed to do that and also mentioned that they would provide some sort of donation to show their appreciation of the clubs support. The net was secured at 0030 local time on 15 April 2007.
Lessons learned from this event were the need for a list of standing volunteers for last minute events and better coordination with event staff prior to event to allow timely planning, etc.
Picnic At The Park Coming Up!
I've just been told by Barbara Frisbee that she will be asking SARC to provide communications support for the High Sierra Cyclists' annual Picnic At The Park bicycle ride from Ridgecrest to Kernville on Saturday 6 October. Frisbee's Bicycle Shop will be the organizer for the ride this year.
This is a 6:00 am start with six checkpoints, start and finish to be supported by one ham each. We keep track of the 100 or so riders at each check point. Greg Roush usually sets up the SARC portable repeater which is used east of Walker Pass. A 10-25 Watt, 2 meter, mobile radio with an exterior antenna will suffice. The last rider usually reaches Kernville by 2 pm. As all riders are accounted for at each check point, that check point is closed and the ham is free to go to Kernville for a free lunch or home or ---? T-shirts and lunch are usually provided by the ride organizers.
I invite those who have participated in this event to be thinking about it over the summer. For a new participant seeking information, feel free to contact Elvy Hopkins NLV at 384-3589
WA7IRW's High Seas Adventures
Once again Greg, WA7IRW, is yachting around the warmer waters, in particular the British Virgin Islands, from 05 to 18 May. Look for Greg on 18.150 to 18.160 MHz around noon and at 6pm daily. Alternate frequencies is 14.330 MHz and second alternate of 21.320 MHz. Give Greg a listen and a call if you hear him.
Size Doesn't Matter - Almost
While hanging out the other day at the local donut shop, uh, The Crest Brain Trust Center, the topic came around to the "unmanly" (read small) 2 Meter (2M) antenna on my vehicle. I stated the obvious that although the antenna may be short, it got the job done. Further defending my manhood, I mentioned that I also used 1/4 wave, 1/2 wave and 5/8 wave antennas depending upon whether I was cruising to Pt Mugu, helping out with a horse ride or going on a strenuous off-road trip where Jerry/KK6PA and Bruce/N8RXJ tried their best to test out the Roll Stability Control system on my vehicle.
Anyway, the lead techie of the Trust, Greg/WA7IRW, promptly reminded us that some antennas are designed to operate with flat ground planes or radials, some with downward sloping ground planes and some do not require ground planes at all. Additionally, some antennas are designed to have a low take-off angle to assist in long range mobile-to-mobile contacts while other antennas have a higher take-off angle to hit those mountain top repeaters.
Greg mentioned that he had an FM Analyzer and thought this would be an excellent experiment to see how the antennas compared to each other when used in a typical Ridgecrest contact. Since we can't change the shape of our vehicles to conform to the requirements of an antenna we might be using at any given moment, the rest of us agreed this would be a good experiment to see how various types of antennas perform on the same vehicle. It was quickly moved and seconded by the group that Greg and I should conduct this experiment as soon as humanly possible.
Three weeks later, Greg and I set up the equipment and conducted our test. The test equipment included an MFJ- 224 2M FM Analyzer modified by tech-guru Greg to accept input from his Yaesu VR-5000 receiver and be extra stable. The test antennas were: Antennex TRABX 1420 (I call this antenna my "coffee cup" antenna), ProAm PAQA 1/4 wave, Cushcraft CS270 1/2 wave, and a Larson 150 5/8 wave. Antennex claims their TRABX 1420 performs comparable to a 1/4 wave antenna. As the results show below, their claim is just a tad off for my installation (12 dB poorer performance). For more information on the TRABX antenna, see my review in the April 2006 Airwaves or email me at [email protected] The transmitter output power was 3.2 watts into a dummy load and each antenna's SWR was 1.2 (Cushcraft) 1.6 (Antennex) and 1.7 (Larson and ProAm). The difference in SWR is so insignificant, it changes the transmit power by less than 0.3 dB! And, the SWRs are good enough that the transmitter output power should not be "folding back" for protection. Each antenna was mounted in succession on the roof of my SUV using a permanent NMO mount. The location provides a slightly curved sheet metal surface of approximately 27" to the front, and an essentially flat sheet metal surface of 26" to each side and 72" to the rear of the antenna.
Test 1 had the test vehicle pointed towards Greg's house. The distance between the test vehicle and Greg's house was approximately 2.9 miles, comprising of trees, houses, streets, moving vehicles, etc. Test 2 had the rear of the test vehicle pointed towards Greg's house to see if the increased ground plane would have any affect. Interestingly, the increased sheet metal had a detrimental affect on all antennas. All readings are in dB and the numbers are negative. (-57 is a stronger signal than a -59).
Antenna Test 1 Test 2 TRABX -71 -72 ProAm 1/4 -59 -60 Cushcraft 1/2 -58 -60 Larson 5/8 -57 -59Considering 6 dB equals 1 S unit on a properly calibrated S-meter and there was only 2 dB difference between the 1/4 wave and 5/8 wave antennas, it is doubtful if one of the antennas would allow a contact to be completed over any other antenna. As you can see, size really doesn't matter for typical 2M communications within the Ridgecrest / Inyokern area. Even the TRABX antenna will allow me to kerchunk the 146.64 translator from anywhere in Ridgecrest at 5 watts, so there's at least a smile on my face!
For all the newly upgraded Techs and freshly minted Generals in the club as well as others who may be interested in jumping into the crazy world of chasing DX on the HF bands, here is some useful websites that can provide information on what's happening and what's in the planning for DX operations and events. I especially like the ADXO website as the information has been simplified for quick reading. Try them all and see which ones are good for you.
Also if your interested in discussing chasing DX with a bunch of seasoned DX'ers or just want to get with a bunch of fellow hams for breakfast and have a good time, the "HI DESERT DX ASSOCIATION" (HIDEXA) meets every Flex Friday morning at La Fiesta Mexican Restaurant (across from McDonalds in Ridgecrest) around 7:30AM to have breakfast and talk about current happenings in the world of chasing DX - the who, what, when and where of DXpeditions. There is also a fair amount of one-up-manships and lies told but its all in fun. Come down and meet the gang. You probably already know most it not all as they are also members of SARC.
Here's the list of DX related websites.....
Announced DX Operations
The 425DXN Bulletin
OPDX Bulletin (US)
RACES Gear To Go
RACES is in the process of upgrading the packet stations to more up to date laptops and move to 440MHz. As a result we now have a surplus of older computers and radios and available for purchase at the May SARC club meeting. The computers are pre Pentium, DOS machines. They may or may not function. A Baycom modem for packet work will be included with each computer. None of the radios or computers have been checked out. No warranty! No returns!
Toshiba T2200SX (no batt)+ Baycom modem -- Free !
Toshiba T1200XE (dark screen, bad batt) + Baycom modem -- Free !
Toshiba T1000XE (no batt) + Baycom modem -- Free !
Zenith ZWL18497 + 2 batteries + Baycom modem - Free!
220 MHz Radios
Kenwood TM 3530A (two of them!) $50ea OBO
Icom IC38A $50 OBO
Long 2 meter beam, at least 9 elements to 12 elements
Timewave DSP-59+ DSP Audio Noise Reduction Filter. Version 3.0 firmware. Reduces random noise, eliminates heterodynes (tuner uppers and cw). 225 combinations of high and low pass filters for voice and digital modes. One small scratch on top cover. Original box and operating manual. Asking $90.00
Ameritron ALS-600S Solid State no tune 600 watt amp with 10/12 Meter mod and switching power supply. Used less than 1 hour. Asking $850.00
LDG AT-1000 Autotuner antenna tuner, handles up to 1000 watts SSB, 750 watts CW, 500 watts digital (RTTY/PSK31, etc). Used less than 2 hours. Asking $375.00
GAP Titan DX antenna 10M-80M 25ft vertical antenna. Good-excellent condition. $50
All items have original manuals and boxes (except antenna). Will consider reasonable offers. Hal/KM6JM 371-3208 or [email protected]
Free to Air Reception from Equatorial Satellites
By Joe Perry Jr, WB6DCO
There is no real history to satellite signals. Way back in the 60's there were a few companies that put some satellites in synchronous orbit, 26,000 miles up around the Earth equator. Those satellites have now grown to one every 1.5 degrees of sky arc. There are now multiple satellites at the same location, some dead or decommissioned and many new TV, Radio and HDTV satellites. Most of the old communication satellites that had proper transponders could be used for Analog TV signals. One analog TV signals takes up 6 or more megahertz bandwidth, so someone had the good idea of putting 20 digital TV signals on one analog channel. Signals like MPEG2, MPEG4 (HDTV), digital TV or digital Radio are available on all the satellites that beam down to Earth. Some satellites use C band and/or Ku band. C band is like 5 gigahertz down-links, and Ku band is like 10 gigahertz down-links. Satellite down-links are signals transmitted from transponders. Each satellite might have 20 to 40 transponders that cover a wide area such as the whole North America country, national channels. Some transponders are called SPOT links. These transmit only to a small 100 to 500 mile area around the larger cities. Spot links can only be picked up if they point in your local area. All equatorial satellites have fixed position in the sky along the Equator starting from 0 degrees at Greenwich England and measuring westward across the USA and out to Hawaii. The most common satellites to view are AMC-6, AMC-5, AMC-3, Galaxy11, AMC-4, Galaxy10R, etc. There are about 65 satellites visible above the Eastern horizon to the Western horizon from the Americas. Some carry signals in Spanish, English, French, Russian, many European, and many Asian stations.
There are two main sources of signal channel down-link information. The main source is www.lyngsat.com, a web site on the internet. Go to this site and view the colored web pages for FREQUENCIES over AMERICA. If you click on Galaxy-25 or T5 at 97 degrees west, as it is called, you will see a list of 24 transponders on C band, and 27 transponders (Tp) at Ku band 11xxx gigahertz and upwards. Note the Vertical (V) or Horizontal (H) indicating the polarization of this transponder. The next column shows the FEED or Channel or Station ID. At the bottom of the page are the color codes. These indicate if the feed or channel is analog/clear, digital/clear, HD/clear or just a wild-feed.
As you can see this web site covers all the Earth. No matter where you live there are Free To Air (FTA) channels you can receive through the use of a home dish station. FTA's are fixed satellites, so we don't have to try to track them across the sky.
A magazine called ORBIT at your local magazine store shows all kinds of channel down-links from about 10 different satellites. Some feeds are clear, and some feeds are encrypted. You generally cannot decode an encrypted channel. There are times when they drop the encryption for tests or free access for short periods.
If you have a DISH network or Direct-TV satellite reception then you are seeing subscribed encrypted DVB (digital video broadcast) channels and some FTA channels. The NASA channel is usually free to air on all down-links. NASA can be found on C band at satellite Ge- 2, channel 9 analog on a Big Ugly Dish receiver. The only Ku band channels for NASA are on Direct-TV and Dish Network satellites. This gives you a ring side seat to the International Space Station videos.
You can setup your own receiving station from old satellite antenna parts. If you have a Big Ugly Dish in your yard it can be used to receive analog and DVB signals directly off the C/Ku horns. If you find an old big oval dish in a yard sale, this is a very good starting point to begin satellite FTA reception. The T5 satellite is an
excellent source of FTA Europe and Asian TV channels in their native languages. The Galaxy-25 or T5 satellites has both analog C band and Ku band down-links. You will have to purchase from EBAY or a store an FTA DVB receiver from 50$ up to 500$ depending on the ease of use you would like to employ. Most FTA receivers have auto-scan for all available transponder channels. All you have to do is learn how to point the antenna at the satellite.
Examples of C and Ku band antennas. There are many types of BUD's. Some are solid fiberglass dishes, some are made up of multiple petals that bolt together, and some have small holes drilled in the dish to lessen the wind friction. The wind can blow a BUD around rather easily and makes for loosing the signal in high winds.
Next Month: FTA signals from space
Updated Sat May 5 16:23:16 PDT 2007